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Not accepted by many, but an interesting thought trying to tackle the quantum gravity standard model problems:-http://www.scientificamerican.com/article.cfm?id=rainbow-gravity-universe-beginning-Seems a little far fetched to me, but anything to explain quantum effects. The Big bang is still the preferred model

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DAVID: Not accepted by many, but an interesting thought trying to tackle the quantum gravity standard model problems:-http://www.scientificamerican.com/article.cfm?id=rainbow-gravity-universe-beginning-Seems a little far fetched to me, but anything to explain quantum effects. The Big bang is still the preferred model-QUOTE: "The result suggests perhaps the universe had no beginning at all, and that time can be traced back infinitely far."-Good to hear that the Big Bang is now only the preferred model as opposed to the standard model. Since we don't know what might have preceded the Big Bang, we continue to face the prospect of time going back infinitely far. So we still have eternal energy, whether conscious or not, as our first cause. And it doesn't make the slightest difference to the God argument one way or the other.

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> dhw: Since we don't know what might have preceded the Big Bang, we continue to face the prospect of time going back infinitely far. So we still have eternal energy, whether conscious or not, as our first cause. And it doesn't make the slightest difference to the God argument one way or the other.-True. As usual anything to get rid of the big bang, because it implies creation.

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David: True. As usual anything to get rid of the big bang, because it implies creation.-Actually, this is even more in favor of creation than the BBT because it would, if confirmed, admit the possibility of something existing 'from time indefinite to time indefinite' as opposed to definitive start and end points.

--
What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

11061 views

David: True. As usual anything to get rid of the big bang, because it implies creation.
> 
>Tony: Actually, this is even more in favor of creation than the BBT because it would, if confirmed, admit the possibility of something existing 'from time indefinite to time indefinite' as opposed to definitive start and end points.-dhw and I have concluded that there must be an eternal First Cause, therefore no starting point.

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DAVID: Not accepted by many, but an interesting thought trying to tackle the quantum gravity standard model problems:-http://www.scientificamerican.com/article.cfm?id=rainbow-gravity-universe-beginning-Seems a little far fetched to me, but anything to explain quantum effects. The Big bang is still the preferred model-QUOTE: "The result suggests perhaps the universe had no beginning at all, and that time can be traced back infinitely far."-Dhw: Good to hear that the Big Bang is now only the preferred model as opposed to the standard model. Since we don't know what might have preceded the Big Bang, we are still faced with the prospect of time going back infinitely far. So we still have eternal energy, whether conscious or not, as our first cause. And it doesn't make the slightest difference to the God argument one way or the other. 
DAVID: True. As usual anything to get rid of the big bang, because it implies creation.
TONY: Actually, this is even more in favor of creation than the BBT because it would, if confirmed, admit the possibility of something existing 'from time indefinite to time indefinite' as opposed to definitive start and end points.-Yep, the Big Bang Theory favours creation, and the No Beginning Theory favours creation even more (which it always did before anybody came up with the Big Bang Theory). So theists can't lose. Nor of course can atheists. Nobody knows what preceded the Big Bang if it happened, so you can still have time going back infinitely far, and in the course of infinite time you can have infinite big bangs and infinite combinations of matter, thereby infinitely reducing the odds against a life-inducing combination. So as I said, whether it's Big Bang or rainbow gravity "doesn't make the slightest difference to the God argument one way or the other."

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> dhw; Yep, the Big Bang Theory favours creation, and the No Beginning Theory favours creation even more (which it always did before anybody came up with the Big Bang Theory). So theists can't lose. Nor of course can atheists. Nobody knows what preceded the Big Bang if it happened, so you can still have time going back infinitely far, and in the course of infinite time you can have infinite big bangs and infinite combinations of matter, thereby infinitely reducing the odds against a life-inducing combination. So as I said, whether it's Big Bang or rainbow gravity "doesn't make the slightest difference to the God argument one way or the other."-True enough. But the argument for God involves much more than the Big Bang.

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DAVID: Not accepted by many, but an interesting thought trying to tackle the quantum gravity standard model problems:
> 
> http://www.scientificamerican.com/article.cfm?id=rainbow-gravity-universe-beginning&... 
> Seems a little far fetched to me, but anything to explain quantum effects. The Big bang is still the preferred model
> 
> QUOTE: "The result suggests perhaps the universe had no beginning at all, and that time can be traced back infinitely far."
> 
> Good to hear that the Big Bang is now only the preferred model as opposed to the standard model. Since we don't know what might have preceded the Big Bang, we continue to face the prospect of time going back infinitely far. So we still have eternal energy, whether conscious or not, as our first cause. And it doesn't make the slightest difference to the God argument one way or the other.-Shortly I'll have more to offer here. I've been reading "A Universe from Nothing" from Krauss, and while honing my cosmological perspective, he pointed out some things I missed...-Such as the fact that an infinitely expanding universe mathematically guarantees a multiverse... David will choke on his morning coffee on that one. But I checked his work, and its correct, even intuitively, which is the approach Krauss took in that book.

--
\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"

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> Matt: Shortly I'll have more to offer here. I've been reading "A Universe from Nothing" from Krauss, and while honing my cosmological perspective, he pointed out some things I missed...
> 
> Such as the fact that an infinitely expanding universe mathematically guarantees a multiverse... David will choke on his morning coffee on that one. But I checked his work, and its correct, even intuitively, which is the approach Krauss took in that book.-I won't choke at all. I'm way ahead of you. Look up Valenkin's recent work and conclusion that even the multiverse had to have a beginning. I've got it here somewhere. Also philosophically you cannot get something from nothing. I have criticisms of Krauss' pseudo-philosophic mistakes in my new book.

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> > Matt: Shortly I'll have more to offer here. I've been reading "A Universe from Nothing" from Krauss, and while honing my cosmological perspective, he pointed out some things I missed...
> > 
> > Such as the fact that an infinitely expanding universe mathematically guarantees a multiverse... David will choke on his morning coffee on that one. But I checked his work, and its correct, even intuitively, which is the approach Krauss took in that book.
> 
> I won't choke at all.: Peter Woit is on my side:- "Video from last weekend's Fundamental Physics Prize scientific meeting at Stanford is now available, in unedited form, here.
 
The first video there is a discussion moderated by Yuri Milner, who does a good job of asking Strominger, Polchinski, Green, Schwarz and Vafa questions, although getting pretty much exactly what you'd expect out of them (the hot topic is firewalls).
 
After skimming through the rest of several hours of video, what struck me is that Milner has managed to all by himself implement the bubble-universe picture of reality that has been propounded at Stanford for many years by Linde, Susskind and others. By smashing tens of millions of dollars into a small target (some prominent academics), he has created a new bubble-universe, with new laws of physics and a new conception of science. In this particular bubble-universe, problems with string theory unification have magically vanished and don't need to be mentioned. Whether a scientific theory can predict anything or not is irrelevant, since you just know what has to be true (the idea with the big money attached to it). The embarrassing fact of no SUSY at the LHC does get fleeting mention, but John Schwarz assures everyone that in his view, there is no question that superpartners exist, whether or not the LHC ever sees them. The multiverse is seen as the answer to all problems, although Cumrun Vafa does warn that maybe one should also look for other answers. Polyakov says that he has nothing against this kind of "Anthropology", except that it is very boring. That's an accurate characterization of the science of the new bubble-universe at Stanford.
 
Most remarkable is the last video, where things truly become causally disconnected from the universe outside Stanford. After a long introduction from Susskind, Michael Green takes the stage with a talk recapitulating the entire history of science, with string theory the successful culmination of this history. He and Schwarz then settle in to accept congratulations from the audience for their great discovery that has made the bubble-universe possible."-http://www.math.columbia.edu/~woit/wordpress/

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> > Matt: Shortly I'll have more to offer here. I've been reading "A Universe from Nothing" from Krauss, and while honing my cosmological perspective, he pointed out some things I missed...
> > 
> > Such as the fact that an infinitely expanding universe mathematically guarantees a multiverse... David will choke on his morning coffee on that one. But I checked his work, and its correct, even intuitively, which is the approach Krauss took in that book.
> 
> I won't choke at all. I'm way ahead of you. Look up Valenkin's recent work and conclusion that even the multiverse had to have a beginning. I've got it here somewhere. Also philosophically you cannot get something from nothing. I have criticisms of Krauss' pseudo-philosophic mistakes in my new book.-The only real philosophical mistake he made is in his dismissal of why questions. I don't disagree with him however, that how questions are imminently preferable. And even if a multiverse is inevitable, and may have had a beginning, it automatically means that chance is no longer a problem. Given that our universe is infinitely large, I still think you can make the argument that every possible configuration of matter in the universe has been created multiple times, purely by natural law. Chance is a false bugaboo, especially the more you play with the total amount of matter we estimate the universe holds, and you add in the nature of "virtual particles" which was the singlehandedly best description of quantum mechanics I have ever read.

--
\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"

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> Matt: The only real philosophical mistake he made is in his dismissal of why questions. I don't disagree with him however, that how questions are imminently preferable. And even if a multiverse is inevitable, and may have had a beginning, it automatically means that chance is no longer a problem. Given that our universe is infinitely large, I still think you can make the argument that every possible configuration of matter in the universe has been created multiple times, purely by natural law. Chance is a false bugaboo, especially the more you play with the total amount of matter we estimate the universe holds, and you add in the nature of "virtual particles" which was the singlehandedly best description of quantum mechanics I have ever read.-The problem is that all you have presented is supposition. Yes, the univedse is large but we can see back to the first 300,000 years. So far we cannot see beyond the COBE but the results so far from Planck still support inflation, a flat universe, continual expansion until heat death, etc. The original reports that the Wilkinson was wrong have just been refuted by more careful analysis of the data. But we cannot see the universe you are supposing. When you show me a bubble universe different than ours I'll then accept your viewpoint. Please don't base your thinkng on String Theory. So far it has opened uop some intersting observations, but most of it is mental masterbation. A good person to follow is Matt Strassler and his blog. He has one of the clearest views of quantum mechanics I have found.

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> > Matt: The only real philosophical mistake he made is in his dismissal of why questions. I don't disagree with him however, that how questions are imminently preferable. And even if a multiverse is inevitable, and may have had a beginning, it automatically means that chance is no longer a problem. Given that our universe is infinitely large, I still think you can make the argument that every possible configuration of matter in the universe has been created multiple times, purely by natural law. Chance is a false bugaboo, especially the more you play with the total amount of matter we estimate the universe holds, and you add in the nature of "virtual particles" which was the singlehandedly best description of quantum mechanics I have ever read.
> 
> The problem is that all you have presented is supposition. Yes, the univedse is large but we can see back to the first 300,000 years. So far we cannot see beyond the COBE but the results so far from Planck still support inflation, a flat universe, continual expansion until heat death, etc. The original reports that the Wilkinson was wrong have just been refuted by more careful analysis of the data. But we cannot see the universe you are supposing. When you show me a bubble universe different than ours I'll then accept your viewpoint. Please don't base your thinkng on String Theory. So far it has opened uop some intersting observations, but most of it is mental masterbation. A good person to follow is Matt Strassler and his blog. He has one of the clearest views of quantum mechanics I have found.-I'm not basing it on String Theory, I'm basing this on observed fact. -1. Our universe is an infinitely expanding universe. 
2. Our universe is therefore infinitely large.
3. If a probability space is infinite, and configurations of matter are finite, than every possible configuration of matter is guaranteed to occur. 
4. "Virtual Particles" aren't String-Theoretic. They are actually necessary for quantum theory to be correct in explaining observed phenomenon. (Basically, without them most quantum physical laws cease to work.) -I'm not a String Theory fan. I follow Krauss, not Brian Greene. An unanswered question by Krauss, if the universe as it is guarantees a multiverse, at what point does this begin? Can we conceivably be living in one now? Is it possible that our "Observable Universe" isn't precisely ONE of these? Krauss describes that in an infinitely expanding universe, the growing expanse of dark energy will create differentiated regions of space that can have different physical laws than what we've observed. This necessarily means, *multiverse.* And no, none of that is based on String Theory. Krauss treats ST in about half a page in his book, with some respect, but directly states that it makes no testable predictions without creating impractically huge experiments. (Although, as I posted before, it has provided techniques to explain some phenomenon that standard physics couldn't. So maybe... JUST maybe... insanity prevails somewhere in the universe...)

--
\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"

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Matt: I follow Krauss, not Brian Greene. An unanswered question by Krauss, if the universe as it is guarantees a multiverse, at what point does this begin? -Still all supposition which may make sense to you but not many:-"Another example of the something for nothing approach
is A Universe From Nothing: Why there is something rather than
nothing (Lawrence Krauss 2012). Michael Brooks, the reviewer,
observes: "Space and time can indeed come from nothing; nothing,
as Krauss explains beautifully, being an extremely unstable
state from which the production of 'something' is pretty much
inevitable. However, the laws of physics can't be conjured from
nothing. In the end, the best answer is that they arise from our
existence within a multiverse, where all the universes have their
own lawsâours being just so for no particular reason. Krauss
contends that the multiverse makes the question of what determined
our laws of nature 'less significant'. Truthfully, it just puts
the question beyond scienceâfor now, at least. That (together
with the frustratingly opaque origins of a multiverse) means
Krauss can't quite knock out those who think there must ultimately
be a prime mover" (http://www.newscientist.com/article/
mg21328472.000-trying-to-make-the-cosmos-out-of-nothing.
html)."-"David Albert, a professor of philosophy at Columbia and the
author of Quantum Mechanics and Experience, has a more devastating
review: "But since the space I have is limited, let me
put those niceties aside and try to be quick, and crude, and concrete.
A century ago, it seems to him, nobody would have made so
much as a peep about referring to a stretch of space without any
material particles in it as nothing. And now that he and his colleagues
think they have a way of showing how everything there is
could imaginably have emerged from a stretch of space like that;
the nutcases are moving the goal posts. He complains that 'some
philosophers and many theologians define and redefine 'nothing'
as not being any of the versions of nothing that scientists currently
describe,' and that 'now, I am told by religious critics that I
cannot refer to empty space as 'nothing,' but rather as a 'quantum
vacuum,' to distinguish it from the philosopher's or theologian's
idealized 'nothing,'" and he does a good deal of railing about 'the
intellectual bankruptcy of much of theology and some of modern
philosophy.' But all there is to say about this, as far as I can see,
is that Krauss is dead wrong and his religious and philosophical
critics are absolutely right" (NY Times Sunday Book Review,
March 23, 2012)."

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Matt: I follow Krauss, not Brian Greene. An unanswered question by Krauss, if the universe as it is guarantees a multiverse, at what point does this begin? 
> 
> Still all supposition which may make sense to you but not many:-And other quotes:-"In an Amazon.com's review of Krauss' book, Don N. Page,
professor of (theoretical gravitational) physics, University of
Alberta, strongly disagrees with Krauss:
Many physicists recently, not least Hawking himself, have
ventured to make many controversial philosophical speculations
going far beyond the science that is presently well
understood.
But in my mind as another physicist working in the
same general area of cosmology (and perhaps focusing
deeper into the quantum aspects of cosmology), its
philosophical argumentations fall far wide of the mark
of answering the age-old question of why there is something
rather than nothing. Krauss essentially redefines the
ancient difficult question into different forms that science
26 David J. Turell, M.D.
can address, discusses possible solutions to the restricted
questions (themselves highly speculative, as Krauss carefully
recognizes) and then seems to imply that these
speculative answers to the restricted questions solve the
ancient difficult problem.
In his preface, Krauss admits that philosophers and
theologians have objected to his meaning of "nothing"
and claim that he does not understand it. Krauss's initial
response is to make the gratuitous ad hominem reply, "I
am tempted to retort here that theologians are experts at
nothing." He then says that for them, "Nothing is 'nonbeing,'
in some vague and ill-defined sense." Well, even
though I am a scientist rather than a philosopher or theologian,
on this issue I agree with them and think that the
idea of nothing as the absence of anything not logically
necessary is much more precise and well-defined than
Krauss's imprecise ideas of "nothing," such as "the absence
of space and time itself."
Page also noted a comment by Richard Dawkins: "In
the final paragraph of his afterword, Richard Dawkins
makes the prematurely triumphalist statement, 'And now
we can read Lawrence Krauss for what looks to me like
the knockout blow.' To me as a fellow scientist, it appears
Krauss has instead swung far wide of the goal, striking
only the air with his philosophical speculations that do not
address the truly deep questions of existence" (http://www.
amazon.com/review/R20NRSZ698T31J)."-"John Horgan of Scientific American is also horrified by Krauss
and Dawkins: "But Krauss asks us to take the quantum theory
of creation seriously, and so does evolutionary biologist Richard
Dawkins. Even the last remaining trump card of the theologian,
"Why is there something rather than nothing?" shrivels up
before your eyes as you read these pages," Dawkins writes in an
afterword to Krauss's book. If On the Origin of Species was biology's
deadliest blow to supernaturalism, we may come to see A
Universe from Nothing as the equivalent from cosmology.( h t t p : / / b l o g s . s c i e n t i f i c a m e r i c a n . c o m / c r o s s -
check/2012/04/23/science-will-never-explain-whytheres-
something-rather-than-nothing/?WT_mc_id=SA_
DD_20120423)."

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That wasn't really a damning review...-He said "nuh uh, theologians and philosophers are right." -There's no meat on those bones.

--
\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"

11083 views

Matt: That wasn't really a damning review...
> 
> He said "nuh uh, theologians and philosophers are right." 
> 
> There's no meat on those bones.-Krauss can't get something from nothing no matter how hard he philosophizes. see my previous note.

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Matt: ...And even if a multiverse is inevitable, and may have had a beginning, it automatically means that chance is no longer a problem. Given that our universe is infinitely large, I still think you can make the argument that every possible configuration of matter in the universe has been created multiple times, purely by natural law. Chance is a false bugaboo, especially the more you play with the total amount of matter we estimate the universe holds, and you add in the nature of "virtual particles" which was the singlehandedly best description of quantum mechanics I have ever read.-We have had this discussion before, but as I see it, David's own concept of God provides complete justification for Matt's statement (which I have put in bold above). You needn't bother with multiverses, string theory, the nature of nothing, the potential infinity of this universe, or the big bang! David and I have agreed that the first cause is eternal energy. David insists that it has always been conscious of itself, and I leave that option open. If energy is eternal, and is capable of transforming itself into matter, there is an eternity and hence an infinity of potential "configurations of matter". The eternal "First Cause" argument therefore works just as well for the atheist's faith in chance as it does for the theist's faith in God.

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Matt: ...And even if a multiverse is inevitable, and may have had a beginning, it automatically means that chance is no longer a problem. Given that our universe is infinitely large, I still think you can make the argument that every possible configuration of matter in the universe has been created multiple times, purely by natural law. Chance is a false bugaboo, especially the more you play with the total amount of matter we estimate the universe holds, and you add in the nature of "virtual particles" which was the singlehandedly best description of quantum mechanics I have ever read.
> 
> dhw: We have had this discussion before, but as I see it, David's own concept of God provides complete justification for Matt's statement (which I have put in bold above). You needn't bother with multiverses, string theory, the nature of nothing, the potential infinity of this universe, or the big bang! David and I have agreed that the first cause is eternal energy. David insists that it has always been conscious of itself, and I leave that option open. If energy is eternal, and is capable of transforming itself into matter, there is an eternity and hence an infinity of potential "configurations of matter". The eternal "First Cause" argument therefore works just as well for the atheist's faith in chance as it does for the theist's faith in God.-I do agree with dhw's statement. There is no way the something we have came from an absolute nothingness. We do not know if a virtual vacuum has always existed at that level of organization or pure energy without spacetime was the beginning.

11170 views

...If energy is eternal, and is capable of transforming itself into matter, -This particular phrase is troubling. -First, we know now that energy in our universe cannot be eternal, and most certainly isn't infinite. You'll recall that the universe is expanding, and that its expansion is acceleration, and that this acceleration is tied to "dark energy?"-One way to look at dark energy is that it is collected in empty space as the universe's expansion does work--if you think of the universe's expansion as the rolling of a wheel, the energy lost to heat friction would be "dark energy." -On big scales, you have the conservation laws--in this case energy, and this might be partly what you're basing your idea of "eternal energy" upon. Well, we know on the quantum scale, that this law isn't true. You've heard me refer to "virtual particles," well, these are particles that don't exist until there is some interaction with the universe--when two particles collide for example, the collision is ruled by the temporary existence of a third particle that blinks into existence for the decision on the event, and then disappears. On the smallest scale then, matter is both created and destroyed regularly. This doesn't suggest that energy is eternal at all. Not to me, at least. All the matter and energy that was ever going to exist in the universe exists now, and because of Black Holes and Dark Energy, I think that these ultimately prove to be drains on both matter AND energy. -And our big supercolliders... they force particles in and out of existence daily... the universe mechanically allows for the creation of "something from nothing" or in your words "turns energy into matter."

--
\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"

11071 views

...If energy is eternal, and is capable of transforming itself into matter, 
> 
> Matt: This particular phrase is troubling. 
> 
> First, we know now that energy in our universe cannot be eternal, and most certainly isn't infinite. 
 All the matter and energy that was ever going to exist in the universe exists now, and because of Black Holes and Dark Energy, I think that these ultimately prove to be drains on both matter AND energy. -
You are assuming that the spacetime we exist in as a virtual vacuum, with quanta popping in and out was present before the Big Bang. Vilenkin has just published a paper in which he says there must be a beginnning, for this one universe and/or multiverses. What was present before the beginning? Guth, Borde cand Vilenkin in their original paper there is no 'before' before the Big Bang. But you can't get something from nothing. Since the universe is energy of whatever forms we measure or suppose, energy is eternal.

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...If energy is eternal, and is capable of transforming itself into matter, 
> > 
> > Matt: This particular phrase is troubling. 
> > 
> > First, we know now that energy in our universe cannot be eternal, and most certainly isn't infinite. 
> All the matter and energy that was ever going to exist in the universe exists now, and because of Black Holes and Dark Energy, I think that these ultimately prove to be drains on both matter AND energy. 
> 
> 
> You are assuming that the spacetime we exist in as a virtual vacuum, with quanta popping in and out was present before the Big Bang. Vilenkin has just published a paper in which he says there must be a beginnning, for this one universe and/or multiverses. What was present before the beginning? Guth, Borde cand Vilenkin in their original paper there is no 'before' before the Big Bang. But you can't get something from nothing. Since the universe is energy of whatever forms we measure or suppose, energy is eternal.-I'm making no such assumption. I'm saying plainly that the universe sprang into being, and that because the universe has a finite mass, it has a finite energy, and because of the existence of dark energy and black holes the amount of available energy to the cosmos is decreasing over time as the universe expands and cools. Nothing here is controversial.-What you're saying here (to me) more like what dhw was after with his "eternal energy." I think the "something from nothing" dilemma is a false dilemma based on millions of years of evolution training us that all things have causes. If God exists, then God came from nothing as well: As I stated years ago, all you're doing is shifting the goalpost. Assume God is real, before the universe. Then, God IS the universe. Then God initiates the big bang: The *universe* has now shifted to "The universe + God" which is still... the Universe. All you've done is applied an artificial separation between the Universe and God. You're still ultimately arguing for a static universe. (If God is eternal so is the universe.) -In Agrippan Skepticism, since this question can be shown to be never-terminating, it isn't a valid question to begin with. -We've gone 'round on this before, to put it simply, existence exists.

--
\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"

11081 views


> Matt: I'm making no such assumption. I'm saying plainly that the universe sprang into being, and that because the universe has a finite mass, it has a finite energy, and because of the existence of dark energy and black holes the amount of available energy to the cosmos is decreasing over time as the universe expands and cools. Nothing here is controversial.-I thought the laws of conservation of energy dictated that the universe would always contain the same amount of energy, but get colder as it expands, with less energy for the spacial size increase. I.E. heat death.-
> 
> Matt: What you're saying here (to me) more like what dhw was after with his "eternal energy." I think the "something from nothing" dilemma is a false dilemma based on millions of years of evolution training us that all things have causes. If God exists, then God came from nothing as well: As I stated years ago, all you're doing is shifting the goalpost. Assume God is real, before the universe. Then, God IS the universe. Then God initiates the big bang: The *universe* has now shifted to "The universe + God" which is still... the Universe. All you've done is applied an artificial separation between the Universe and God. You're still ultimately arguing for a static universe. (If God is eternal so is the universe.)-Unless He always existed and created the universe from within Him. Panentheism. 
> 
> Matt; In Agrippan Skepticism, since this question can be shown to be never-terminating, it isn't a valid question to begin with. 
> 
> We've gone 'round on this before, to put it simply, existence exists.-Yes, something is eternal. I have my choice, what is yours?

11117 views


> > Matt: I'm making no such assumption. I'm saying plainly that the universe sprang into being, and that because the universe has a finite mass, it has a finite energy, and because of the existence of dark energy and black holes the amount of available energy to the cosmos is decreasing over time as the universe expands and cools. Nothing here is controversial.
> 
> I thought the laws of conservation of energy dictated that the universe would always contain the same amount of energy, but get colder as it expands, with less energy for the spacial size increase. I.E. heat death.
> -Energy is still conserved, but in black holes it becomes useless (you aren't going to extract any matter/energy) and in dark energy, that energy isn't usable to do work. So while we're dealing with finite sums, we're still losing energy in the perspective of being able to do useful work. -> 
> > 
> > Matt: What you're saying here (to me) more like what dhw was after with his "eternal energy." I think the "something from nothing" dilemma is a false dilemma based on millions of years of evolution training us that all things have causes. If God exists, then God came from nothing as well: As I stated years ago, all you're doing is shifting the goalpost. Assume God is real, before the universe. Then, God IS the universe. Then God initiates the big bang: The *universe* has now shifted to "The universe + God" which is still... the Universe. All you've done is applied an artificial separation between the Universe and God. You're still ultimately arguing for a static universe. (If God is eternal so is the universe.)
> 
> Unless He always existed and created the universe from within Him. Panentheism. 
> > -Which still doesn't negate you from answering the question: How did God come from nothing? -> > Matt; In Agrippan Skepticism, since this question can be shown to be never-terminating, it isn't a valid question to begin with. 
> > 
> > We've gone 'round on this before, to put it simply, existence exists.
> 
> Yes, something is eternal. I have my choice, what is yours?-There isn't sufficient evidence to come to a conclusion. C'mon, there's a reason I'm an agnostic. You really think it's that simple?

--
\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"

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DAvid Yes, something is eternal. I have my choice, what is yours?
> 
> Matt: There isn't sufficient evidence to come to a conclusion. C'mon, there's a reason I'm an agnostic. You really think it's that simple?-Still want to avoid a first cause? Standard Greek philosophy. Why is there anything?

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Unless He always existed and created the universe from within Him. Panentheism. 
> > -
I wanted to concentrate on this a little more. You're shifting goalposts. The only real difference between you and I, is that I really don't care if the universe's origin had an intelligent origin. Intelligence necessitates existence in the first place: Which means God before creation IS the universe. The very fact that you cannot present a counter argument to this, and the fact that you cannot present a counter argument to the concept that God + the Universe is simply the universe... and by extension that the "something from nothing" argument still applies, fully--smack-in-the-face-fully--to you... -
Well, I'll just wait until you can explain to me how a God that exists before the universe doesn't require a causal explanation.

--
\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"

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> 
> Matt: Well, I'll just wait until you can explain to me how a God that exists before the universe doesn't require a causal explanation.-It is the same issue. Eithr something eternal or somehow we get something from nothing. Logically, something eternal. I choose energy in the form of a universal intelligence. God is eternal. And a universe from quantum perturbations is not something from nothing. Absolute void makes no sense as a fist cause. Something is eternal. Our spacetime? No. It had a beginning.

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This is the final solution for many theoretical cosmologists to explain why our universe allows for life by fine tuning. Going from science to philosophical guess work:-"Physics was different until now. Almost everything in the universe could be explained in terms of fundamental laws like Einstein's theory of gravity (general relativity) or the laws of quantum mechanics. If you wanted to explain the shape and structure of a galaxy you could seek the explanation in the precise motion of the various particles governed by the laws of gravity. If you wanted to explain why water is H20 and not H30 you could seek the explanation in the principles of quantum mechanics that in turn dictate the laws of chemical bonding.
 
"But beyond this wildly successful level of explanation seems to lie an impasse. The problem arises when you try to explain one of the most profound facts of nature, the fact that the fundamental constants of nature are fine-tuned to a fault, that the universe as we know it would not exist if these constants had even slightly different values. For instance, it is impossible to imagine life existing had the strength of the strong force binding nuclei together been even a few percent smaller or larger. Scientists have struggled for decades to explain why other numbers like the value of Planck's constant or the electron's mass are what they are. It seems now that they are giving up trying to do this, or at least giving up trying to do it the way they always have.
 
"The point was driven home to me by two books that I read recently. One was Max Tegmark's "The Mathematical Universe". In the book Tegmark takes us on a dizzying journey through modern physics that ends in the fanciful realm of multiple universes. It's hardly the first book to do so. Multiple universes have been invoked to explain many problems in physics, but their most common use is try to explain (or explain away, as some seem to rightly think) the problem of the fundamental constants. The purported "solution" sounds simple; we can stop wondering why the fundamental constants have the precise values that they do if we assume the existence of a potentially infinite number of universes, each of which has a different set of values for the constants. Our universe just happens to have the right combination that allows sentient life to arise and ask such questions in the first place.
 
"Leaving aside the fact that multiple universes still belong to speculation and science fiction rather than science, what is really striking about them to me is that they have finally transported physics into the realm of biology. What physicists are essentially saying is that there have been several universes in the past and there are likely several universes in the present, and our unique universe with its specific combination of fundamental constants is an accident."-http://blogs.scientificamerican.com/the-curious-wavefunction/2014/01/21/should-physicists-stop-looking-for-fundamental-laws/

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"But beyond this wildly successful level of explanation seems to lie an impasse. The problem arises when you try to explain one of the most profound facts of nature, the fact that the fundamental constants of nature are fine-tuned to a fault, that the universe as we know it would not exist if these constants had even slightly different values. >-This quote reminds me of what I concluded while contemplating God and reality when "frozen in time" while ill. That if there is a God, it would be found in the changeless constant of the fabric of our universe which is itself [created by] change. Even the scripture's conclude, God never changes - which has really allowed fundamentalist to drag their feet evolving with time. Yet, the only thing that doesn't change is change itself. So, for me, this scripture is saying, God IS the changelessness of change [edited: in other words: It is what It is. And the thing about "IT" (change), it is so momentarily fleeting, it is impossible to nail down or to give IT expression. And so = God.]

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> bbella:This quote reminds me of what I concluded while contemplating God and reality when "frozen in time" while ill. That if there is a God, it would be found in the changeless constant of the fabric of our universe which is itself [created by] change. Even the scripture's conclude, God never changes - which has really allowed fundamentalist to drag their feet evolving with time. Yet, the only thing that doesn't change is change itself. So, for me, this scripture is saying, God IS the changelessness of change [edited: in other words: It is what It is. And the thing about "IT" (change), it is so momentarily fleeting, it is impossible to nail down or to give IT expression. And so = God.]-This is why I think God is the consciousness or mind of the universe, unchanging but guiding change.

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DAVID: But beyond this wildly successful level of explanation seems to lie an impasse. The problem arises when you try to explain one of the most profound facts of nature, the fact that the fundamental constants of nature are fine-tuned to a fault, that the universe as we know it would not exist if these constants had even slightly different values. -BBella: This quote reminds me of what I concluded while contemplating God and reality when "frozen in time" while ill. That if there is a God, it would be found in the changeless constant of the fabric of our universe which is itself [created by] change. Even the scripture's conclude, God never changes - which has really allowed fundamentalist to drag their feet evolving with time. Yet, the only thing that doesn't change is change itself. So, for me, this scripture is saying, God IS the changelessness of change [edited: in other words: It is what It is. And the thing about "IT" (change), it is so momentarily fleeting, it is impossible to nail down or to give IT expression. And so = God.]-DAVID: This is why I think God is the consciousness or mind of the universe, unchanging but guiding change.-This exchange brings me back into the fray, which may or may not be a good thing. Firstly, if the ingredients of a substance change, it will be a different substance. Our universe is fine-tuned to support life as we know it. A different universe might be fine-tuned to support a different form of life. The quote is not proof of deliberate creation ... it merely states tautologically that things are as they are, and if they were not as they are, they would be different. Secondly, I suspect that David has misunderstood BBella (but she will correct me if I'm wrong). Nothing ever stays the same, and so the only constant is change. If there is a god, it is a form of energy that transmutes itself into ever changing combinations of matter. When eventually our own solar system dies, and we die with it, the history of our universe will be the blink of an eye, since "first cause" energy is eternal, and this energy (whether conscious or not) will continue to change itself for ever and ever.-This should not be taken as an argument either for or against design. I am simply questioning the validity of any conclusion drawn from examining the universe "as we know it". Of course we can't examine universes we don't know, but the suggestion that they exist, existed or will exist is no more and no less fanciful than the suggestion that there exists a form of "divine" consciousness we don't know and can't examine.

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bbella: the only thing that doesn't change is change itself. So, for me, this scripture is saying, God IS the changelessness of change [edited: in other words: It is what It is. And the thing about "IT" (change), it is so momentarily fleeting, it is impossible to nail down or to give IT expression. And so = God.][/i]
> 
> DAVID: This is why I think God is the consciousness or mind of the universe, unchanging but guiding change.
> 
> dhw:This exchange brings me back into the fray, which may or may not be a good thing. ....... I suspect that David has misunderstood BBella (but she will correct me if I'm wrong). Nothing ever stays the same, and so the only constant is change. If there is a god, it is a form of energy that transmutes itself into ever changing combinations of matter.-Welcome back. I'm delighted you feel comfortable enough with yourself to begin to externalize from your innnermost feelings, which still must be quite raw. I'm sure I have bbella right. You are interpreting whatever is eternal as changing in total, and I don't think that is what she meant. I know it is not what I mean when I think of an eternal God. He does not change but as I think He is a part of the universe as well as outside of it, the changing universe represents a changing portion of Him but a discrete portion of Him is unchanging and in control of the change, and that is the main part outside of
the universe.-At any rate, bbella has to tell us what she meant.

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bbella: the only thing that doesn't change is change itself. So, for me, this scripture is saying, God IS the changelessness of change [edited: in other words: It is what It is. And the thing about "IT" (change), it is so momentarily fleeting, it is impossible to nail down or to give IT expression. And so = God.][/i]
> > 
> > DAVID: This is why I think God is the consciousness or mind of the universe, unchanging but guiding change.
> > 
> > dhw:This exchange brings me back into the fray, which may or may not be a good thing. ....... I suspect that David has misunderstood BBella (but she will correct me if I'm wrong). Nothing ever stays the same, and so the only constant is change. If there is a god, it is a form of energy that transmutes itself into ever changing combinations of matter.
> 
>David: Welcome back. I'm delighted you feel comfortable enough with yourself to begin to externalize from your innnermost feelings, which still must be quite raw. I'm sure I have bbella right. You are interpreting whatever is eternal as changing in total, and I don't think that is what she meant. I know it is not what I mean when I think of an eternal God. He does not change but as I think He is a part of the universe as well as outside of it, the changing universe represents a changing portion of Him but a discrete portion of Him is unchanging and in control of the change, and that is the main part outside of
> the universe.
> 
> At any rate, bbella has to tell us what she meant.-At the risk of waxing a little poetic, the prophet Zechariah described the character of God with the words "sh'mo ehhad" translated as 'His Name is One'. Mathematics will tell us that every possible combination of numbers is contained within the number 1. 1 doesn't have to change because every conceivable sequence of numbers exists between one and nothing, the possibilities within it are endless and infinite. One is unity. One is harmony. One is complete. -In Game Design, we often describe absolutely everything as a value between 0 and 1. And why not? Is is absolutely perfect in its simplicity. One is the only number that, when divided by itself, is one, and likewise when multiplied by itself. In order to have anything, as opposed to nothing, you must at least have one. You can not have less than one without there being nothing. Nothing can be added, nor taken away. -Bella has often expressed the thought about us all being part of one. Unfortunately, few ever realize how true that statement is, and so we remain fractious, but a shadow of what could be. Ironically, Bella, the 'scriptures' says that he names himself 'I am what I shall prove to be' or, I am whatever I need to be. Without limitation, without reservations, absolutely complete.

--
What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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Tony: Bella has often expressed the thought about us all being part of one. Unfortunately, few ever realize how true that statement is, and so we remain fractious, but a shadow of what could be. Ironically, Bella, the 'scriptures' says that he names himself 'I am what I shall prove to be' or, I am whatever I need to be. Without limitation, without reservations, absolutely complete.-At the same time theologists refer to God as utter simplicity,not complex. 'One' is simple. Seems to fit your concept.

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Complexity is a human construct. I am not saying God is 'simple' by any definition of the word that I am aware of. He is so far beyond our ability to truly comprehend that those two words have no meaning. I would say that he is not 'needlessly complex'. In that sense, and in that sense only, I would agree that he is simple. There is nothing that can be added or taken away. In that sense, yes, he could be called simple.

--
What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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Tony: Complexity is a human construct. I am not saying God is 'simple' by any definition of the word that I am aware of. He is so far beyond our ability to truly comprehend that those two words have no meaning. I would say that he is not 'needlessly complex'. In that sense, and in that sense only, I would agree that he is simple. There is nothing that can be added or taken away. In that sense, yes, he could be called simple.-I believe he is pure energy and pure intellect. Simply a universal mind or consciousness.

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TONY: Bella has often expressed the thought about us all being part of one. Unfortunately, few ever realize how true that statement is, and so we remain fractious, but a shadow of what could be. Ironically, Bella, the 'scriptures' says that he names himself 'I am what I shall prove to be' or, I am whatever I need to be. Without limitation, without reservations, absolutely complete.-DAVID: At the same time theologists refer to God as utter simplicity,not complex. 'One' is simple. Seems to fit your concept.-I don't think you need to believe in God to feel or believe in the oneness of all things. Buddhists manage quite well without believing in a supreme, conscious being. "I am what I shall prove to be" or "whatever I need to be" might just as well mean an impersonal Absolute (the words having been put in its mouth by a poetic scribe). Humans who say their God is "utter simplicity", or who offer any other description, have no evidence except their own and other people's opinions. "Without limitation, without reservations, absolutely complete" = BBella's ALL THAT IS, and that does not tell us whether the ALL THAT IS is a conscious being or a mindless mass of energy constantly and impersonally transmuting itself into different forms and combinations of matter. It's the same old story: life allows for whatever interpretation we humans like to put on it, and the same applies to whatever power led to life in the first place.

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> DAVID: At the same time theologists refer to God as utter simplicity,not complex. 'One' is simple. Seems to fit your concept.
> 
> dhw: I don't think you need to believe in God to feel or believe in the oneness of all things. -You shifted the discussion. There is a line of reasoning in theology, considering God alone, that He is not complex but utter simplicity. It fits my view of a universall consciousness: pure energy focused mentation.

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dhw: I do not see the Big Bang or the multiverse theory, or an infinite number of past and future universes, as providing any evidence for or against the existence of a designer.-DAVID: Philosopher John Leslie's famous conclusion to his book, "Universes" fits here:" Much evidence suggests...That God is real and/or there exist vastly many, very varied universes." Note that the "and/or" allows for God to create one or many!-Indeed. And note that "and/or" also allows for the UNREALITY of God if there are vastly many, very varied universes. So it would appear that John Leslie's argument and mine are identically agnostic.
 
********-DAVID: At the same time theologists refer to God as utter simplicity,not complex. 'One' is simple. Seems to fit your concept.
dhw: I don't think you need to believe in God to feel or believe in the oneness of all things.
 DAVID: You shifted the discussion. There is a line of reasoning in theology, considering God alone, that He is not complex but utter simplicity. It fits my view of a universall consciousness: pure energy focused mentation.-The part of my post you have quoted was in response to Tony: "Bella has often expressed the thought about us all being part of one. [...] Bella, the 'scriptures' says that he names himself 'I am what I shall prove to be' or, I am whatever I need to be. Without limitation, without reservations, absolutely complete." -I then commented on your claim that God is "utter simplicity" as follows: "Humans describing their God as "utter simplicity", or offering any other description, have no evidence except their own and other people's opinions." I stand by that response.-I'm also surprised that since human consciousness is so complex as to defy all our scientists' attempts to understand it, you should consider divine consciousness to be utterly simple. If this is so, do please explain how pure energy can "simply" be conscious of itself, whereas the consciousness of energy in the form of matter is beyond our understanding.

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> dhw: Indeed. And note that "and/or" also allows for the UNREALITY of God if there are vastly many, very varied universes. So it would appear that John Leslie's argument and mine are identically agnostic.-No, Leslie is simply allowing that your form of agnosticism cannot be logically refuted.
> 
> ********
> dhw: I'm also surprised that since human consciousness is so complex as to defy all our scientists' attempts to understand it, you should consider divine consciousness to be utterly simple. If this is so, do please explain how pure energy can "simply" be conscious of itself, whereas the consciousness of energy in the form of matter is beyond our understanding.-I don't have enough background in theology to do more than offer the comment, as I did, that God is considered utterly simple by theologans. As you consider consciousness beyond our understanding, as God is also beyond understanding.

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DHW: I'm also surprised that since human consciousness is so complex as to defy all our scientists' attempts to understand it, you should consider divine consciousness to be utterly simple. If this is so, do please explain how pure energy can "simply" be conscious of itself, whereas the consciousness of energy in the form of matter is beyond our understanding.-Have you ever noticed how most things in physics and biology, once we actually understand them, become so utterly simple that we are amazed that we never realized it before?

--
What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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DAVID: But beyond this wildly successful level of explanation seems to lie an impasse. The problem arises when you try to explain one of the most profound facts of nature, the fact that the fundamental constants of nature are fine-tuned to a fault, that the universe as we know it would not exist if these constants had even slightly different values. 
> 
> BBella: This quote reminds me of what I concluded while contemplating God and reality when "frozen in time" while ill. That if there is a God, it would be found in the changeless constant of the fabric of our universe which is itself [created by] change. Even the scripture's conclude, God never changes - which has really allowed fundamentalist to drag their feet evolving with time. Yet, the only thing that doesn't change is change itself. So, for me, this scripture is saying, God IS the changelessness of change [edited: in other words: It is what It is. And the thing about "IT" (change), it is so momentarily fleeting, it is impossible to nail down or to give IT expression. And so = God.]
> 
> DAVID: This is why I think God is the consciousness or mind of the universe, unchanging but guiding change.
> 
>[dhw] Nothing ever stays the same, and so the only constant is change. If there is a god, it is a form of energy that transmutes itself into ever changing combinations of matter... This should not be taken as an argument either for or against design. -Yes, dhw, what you wrote above does sum up to a tee what I was saying. As for an eternal designer: A Conscious Self Aware Being that calls itself God or I Am, as the scriptures convey, that designed all that now IS from the beginning? I don't know. But I do completely understand how and why (the ONE thing that does not change: the changelessness of change) could be worshiped and called God. When you observe the ability of our consciousness itself to effect the ever changing fabric of All That IS, it gives a clue (to me) or lends itself to the idea that consciousness itself has power over the changing state of matter. It's like, if something is observed for very long, more times than not it will eventually appear to have some form of consciousness. It is understandable that we then conclude consciousness was there before we observed it. But, it is also possible to conclude that by the very act of our concluding (belief) we effected the very fabric of what we observed and may have "awakened" consciousness within it. Or, it may appear conscious because we look thru conscious eyes and conclude it has consciousness, altho it may not. I don't know which. I remain open.

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[dhw] Nothing ever stays the same, and so the only constant is change. If there is a god, it is a form of energy that transmutes itself into ever changing combinations of matter... This should not be taken as an argument either for or against design.
 
BBELLA: Yes, dhw, what you wrote above does sum up to a tee what I was saying. As for an eternal designer: A Conscious Self Aware Being that calls itself God or I Am, as the scriptures convey, that designed all that now IS from the beginning? I don't know. But I do completely understand how and why (the ONE thing that does not change: the changelessness of change) could be worshiped and called God. When you observe the ability of our consciousness itself to effect the ever changing fabric of All That IS, it gives a clue (to me) or lends itself to the idea that consciousness itself has power over the changing state of matter. It's like, if something is observed for very long, more times than not it will eventually appear to have some form of consciousness. It is understandable that we then conclude consciousness was there before we observed it. But, it is also possible to conclude that by the very act of our concluding (belief) we effected the very fabric of what we observed and may have "awakened" consciousness within it. Or, it may appear conscious because we look thru conscious eyes and conclude it has consciousness, altho it may not. I don't know which. I remain open.-Thank you for these very illuminating observations. I can only nod approvingly at the sound of so many nails being hit on their heads! The plain fact is that none of us know the origin of consciousness, whether consciousness exists independently of those forms we are familiar with, or the extent to which our own consciousness imposes or influences the patterns we observe. I have tried to develop your admirably balanced line of thought in my response to Tony.

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bbella: But, it is also possible to conclude that by the very act of our concluding (belief) we effected the very fabric of what we observed and may have "awakened" consciousness within it. Or, it may appear conscious because we look thru conscious eyes and conclude it has consciousness, altho it may not. I don't know which. I remain open.[/i]
> 
> dhw:Thank you for these very illuminating observations. I can only nod approvingly at the sound of so many nails being hit on their heads! The plain fact is that none of us know the origin of consciousness, whether consciousness exists independently of those forms we are familiar with, or the extent to which our own consciousness imposes or influences the patterns we observe. I have tried to develop your admirably balanced line of thought in my response to Tony.-I'll remind both of you that our human consciousness affects every quantum experiment we try.

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An infinite discussion, almost, of multiverse possibilities. IMHO Tegemark is not logical and dismisses Occam:-http://blogs.scientificamerican.com/guest-blog/2014/02/04/are-parallel-universes-unscientific-nonsense-insider-tips-for-criticizing-the-multiverse/

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Latest proposal. Again circles in the CMB:-http://www.sciencedaily.com/releases/2014/07/140717124800.htm

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Just came across this comment while browsing:-dhw says: The eternal "First Cause" argument therefore works just as well for the atheist's faith in chance as it does for the theist's faith in God.-The difference is that chance is known to exist so no faith is required. -I'm puzzled where the idea that the universe is infinite comes from in this discussion. There is no evidence that it is anything but finite.

--
GPJ

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> George:I'm puzzled where the idea that the universe is infinite comes from in this discussion. There is no evidence that it is anything but finite.-If you look into the atheist theoretical cosmologists' proposals many of them state that the universe is really infinite beyond the CMB we can see and allows for bubble universes beyond ours as a form of the multiverse theory. A few references: -http://www.esa.int/Our_Activities/Space_Science/People/Is_the_Universe_finite_or_infinite_An_interview_with_Joseph_Silk-http://space.mit.edu/home/tegmark/mathematical.html-http://curious.astro.cornell.edu/question.php?number=476-http://www.scientificphilosophy.com/Downloads/IUT.pdf-Off the top of my head, folks like Coyne and Krauss think it is infinite.

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GEORGE: Just came across this comment while browsing:
dhw says: The eternal "First Cause" argument therefore works just as well for the atheist's faith in chance as it does for the theist's faith in God.
The difference is that chance is known to exist so no faith is required.-A fair enough reprimand for taking intellectual short cuts! What I mean is that theists believe first cause eternal energy is conscious of itself, and has deliberately designed the universe and life. This requires faith. If atheists were to accept the concept of an eternal first cause, it would be mindless, and consequently the complexities of the universe and life would have originated by chance ... i.e. there was no conscious form of energy that designed them. This also requires faith. I consider both concepts to be equally beyond belief. (See below for why the eternal first cause works equally well for both parties.)-GEORGE: I'm puzzled where the idea that the universe is infinite comes from in this discussion. There is no evidence that it is anything but finite.-I'm not sure what statements you're referring to here, but the line I have been following with David is that there has to be a first cause, and if we accept that this is energy, there is no reason to suppose that it is limited by time. Whether it is conscious (God) or mindless, it is perfectly feasible that it would have gone on and will go on producing universes ad infinitum. Some theists like to use the Big Bang as "evidence" of a single creation, while some atheists like to use the multiverse theory as a means of reducing the odds against chance producing life (the more universes you have, the greater the likelihood of the right combination). I do not see the Big Bang or the multiverse theory, or an infinite number of past and future universes, as providing any evidence for or against the existence of a designer.

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> GEORGE: I'm puzzled where the idea that the universe is infinite comes from in this discussion. There is no evidence that it is anything but finite.
> 
> dhw: I'm not sure what statements you're referring to here, .......I do not see the Big Bang or the multiverse theory, or an infinite number of past and future universes, as providing any evidence for or against the existence of a designer.-Philosopher John Leslie's famous conclusion to his book, "Universes" fits here:" Much evidence suggests...That God is real and/or there exist vastly many, very varied universes." Note that the "and/or" allows for God to create one or many!

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I would like to get a firm answer from an atheist or agnostic on something, though. How many lines of indirect evidence would it take for them to admit/accept the possibility/probability of a designed universe, and thus the presence of a designer?-What I take from many of the discussions that I see is that less proof would be needed to get them to accept the idea of the tooth fairy or magic than it would for them to accept a designer. We have less evidence for multi-verses than we do for design, yet scientist are willing to accept the possibility of a multi-verse but not a designer. The theories of dark matter, dark energy, and other flights of fancy are based on less evidence than that of a designer. So, the question, how many lines of evidence would it take to get a scientist to say 'I admit that the possibility of a designer is at least as good, if not better, than the possibility of random chance creating everything that exists.

--
What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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Tony: how many lines of evidence would it take to get a scientist to say 'I admit that the possibility of a designer is at least as good, if not better, than the possibility of random chance creating everything that exists.-I'm on your side. Design is so obvious I can't answer you.

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TONY: I would like to get a firm answer from an atheist or agnostic on something, though. How many lines of indirect evidence would it take for them to admit/accept the possibility/probability of a designed universe, and thus the presence of a designer?
What I take from many of the discussions that I see is that less proof would be needed to get them to accept the idea of the tooth fairy or magic than it would for them to accept a designer. We have less evidence for multi-verses than we do for design, yet scientist are willing to accept the possibility of a multi-verse but not a designer. The theories of dark matter, dark energy, and other flights of fancy are based on less evidence than that of a designer. So, the question, how many lines of evidence would it take to get a scientist to say 'I admit that the possibility of a designer is at least as good, if not better, than the possibility of random chance creating everything that exists.-I can't speak for atheist scientists, but I'll try to answer as an agnostic non-scientist. I find the evidence for design very compelling, but I see no evidence of a single conscious designer. The design we know may come from within the materials themselves, and whatever degree of awareness is necessary for each design may have evolved within individual collections of matter. This is the form of panpsychism that attributes mental aspects to all spatio-temporal things. Instead of one single conscious being, we have untold billions of consciousnesses (though I prefer to use the term intelligence) of varying degrees, gradually evolving into more and more complex entities. It all comes down to the origin and nature of consciousness, and BBella has given us a masterly summary of the problem. Theists hide behind the cop-out argument that their God's consciousness was always there so they don't have to explain it. Atheists rely on the cop-out argument that it evolved by way of random chance starting things off. The third possibility is the cop-out panpsychist hypothesis outlined above.
 
My agnostic answer to your question can only be that none of these three hypotheses offer a convincing explanation of the origin of consciousness (and by extension the designs that have stemmed from consciousness). Each is equally possible, but I see no reason to give one precedence over the others.

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tony: the possibility of a designer is at least as good, if not better, than the possibility of random chance creating everything that exists.[/i]
> 
> dhw: The design we know may come from within the materials themselves, and whatever degree of awareness is necessary for each design may have evolved within individual collections of matter. This is the form of panpsychism that attributes mental aspects to all spatio-temporal things.-To which I continue to raise the same issue: where did the information come from to allow this supposed mechanism. Information is organized knowledge. it has to have a source you can point to, but you can't as an agnostic.- 
> dhw: My agnostic answer to your question can only be that none of these three hypotheses offer a convincing explanation of the origin of consciousness (and by extension the designs that have stemmed from consciousness). Each is equally possible, but I see no reason to give one precedence over the others.-And I think they are not equal since you cannot give me a source for the underlying information.

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Dhw: The design we know may come from within the materials themselves, and whatever degree of awareness is necessary for each design may have evolved within individual collections of matter. This is the form of panpsychism that attributes mental aspects to all spatio-temporal things.-DAVID: To which I continue to raise the same issue: where did the information come from to allow this supposed mechanism. Information is organized knowledge. It has to have a source you can point to, but you can't as an agnostic.-You cannot point to a source either, other than a "supposed" power so nebulous that it has no meaning. You call it God, and say it is hidden, beyond our understanding, unknown, unknowable, has always been there, should not be loaded with human attributes, and belief in it requires an act of blind faith! This is why my post continues: "Theists hide behind the cop-out argument that their God's consciousness was always there so they don't have to explain it. Atheists rely on the cop-out argument that it evolved by way of random chance starting things off. The third possibility is the cop-out panpsychist hypothesis outlined above." They are ALL cop-outs.-Dhw: (to BBella) Thank you for these very illuminating observations. I can only nod approvingly at the sound of so many nails being hit on their heads! The plain fact is that none of us know the origin of consciousness, whether consciousness exists independently of those forms we are familiar with, or the extent to which our own consciousness imposes or influences the patterns we observe. -DAVID: I'll remind both of you that our human consciousness affects every quantum experiment we try.-That is what we mean by "the extent to which our consciousness...influences the patterns we observe." BBella's brilliantly balanced summary of the various alternatives leaves open all the questions you so resolutely seek to close by your faith in a single, eternal, unchanging, universal consciousness. Your belief is understandable, but no more so than a belief in countless separate consciousnesses or the lucky break inevitably occurring in Leslie's "vastly many, very varied universes". I can still see no reason why one cop-out should be given precedence over the others.

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DHW: The design we know may come from within the materials themselves, and whatever degree of awareness is necessary for each design may have evolved within individual collections of matter. -Not until those materials themselves exist and have some measure of awareness, which in turn requires something to design them. ->DHW: This is the form of panpsychism that attributes mental aspects to all spatio-temporal things. Instead of one single conscious being, we have untold billions of consciousnesses (though I prefer to use the term intelligence) of varying degrees, gradually evolving into more and more complex entities. It all comes down to the origin and nature of consciousness, and BBella has given us a masterly summary of the problem. Theists hide behind the cop-out argument that their God's consciousness was always there so they don't have to explain it. -Actually, I only say that it is more likely that a single entity became self-aware and eventually grew to the point that it could begin to create. Now, I will freely admit that it is an unknown, and is unknowable. However, I did admit that faith is a requirement for any of these solutions.-Atheists rely on the cop-out argument that it evolved by way of random chance starting things off. The third possibility is the cop-out panpsychist hypothesis outlined above.
> 
> DHW: My agnostic answer to your question can only be that none of these three hypotheses offer a convincing explanation of the origin of consciousness (and by extension the designs that have stemmed from consciousness). Each is equally possible, but I see no reason to give one precedence over the others.-This is the thrust of my question here. How many lines of evidence would be required to meet the criteria of a 'convincing explanation', given the understanding that any answer will require some measure of faith?

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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DHW: The design we know may come from within the materials themselves, and whatever degree of awareness is necessary for each design may have evolved within individual collections of matter. -TONY: Not until those materials themselves exist and have some measure of awareness, which in turn requires something to design them.-I have no problem with the concept of energy transforming itself mindlessly into materials. It is awareness which is the problem for me, and once again I do not see an answer to it in the claim that lesser degrees of awareness require design, whereas your God's super-awareness did NOT require design!
 
TONY: Actually, I only say that it is more likely that a single entity became self-aware and eventually grew to the point that it could begin to create. Now, I will freely admit that it is an unknown, and is unknowable. However, I did admit that faith is a requirement for any of these solutions.-And that is the reason why your question ("How many lines of evidence would be required to meet the criteria of a 'convincing explanation'...?") seems to me to collapse in on itself. It's not a matter of "how many", but of whether an individual can subjectively view any "evidence" as convincing enough for him to abandon his own rational awareness that the answer is unknown and unknowable, and then to take a blind leap of faith. On this forum we have pursued every "line of evidence" we can think of, and I have extrapolated from these lines three possible sources of life ... a conscious designer, a huge stroke of luck, countless mini-designers (matter containing different degrees of intelligence). I do not find the "evidence" for any of them convincing enough to enable me to take the leap. Perhaps it would be more fruitful for our discussion if you were to tell us why you are sufficiently convinced by the first hypothesis to ignore your own awareness of unknowability, and to conclude that there is more "evidence" for your single entity than there is for multiple entities or for the huge stroke of luck!-************ -DHW (to David): I'm also surprised that since human consciousness is so complex as to defy all our scientists' attempts to understand it, you should consider divine consciousness to be utterly simple. If this is so, do please explain how pure energy can "simply" be conscious of itself, whereas the consciousness of energy in the form of matter is beyond our understanding.-TONY: Have you ever noticed how most things in physics and biology, once we actually understand them, become so utterly simple that we are amazed that we never realized it before?-Have you ever noticed how people with strong beliefs see what they want to see? Some folk still talk of "simple" forms of life, but the more science delves into life, the more complex even these "simple" forms appear to be. The cell has proven to be amazingly complex. Do you see the human brain, the seat and perhaps also the source of our consciousness, as being simple? The argument for design actually rests on physical and biological structures being too complex to have arisen by chance. And yet David's theologians tell us the consciousness that designed them is "utter simplicity". How the heck do they know? And what does it actually mean?

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I would like to get a firm answer from an atheist or agnostic on something, though. How many lines of indirect evidence would it take for them to admit/accept the possibility/probability of a designed universe, and thus the presence of a designer?
> 
> What I take from many of the discussions that I see is that less proof would be needed to get them to accept the idea of the tooth fairy or magic than it would for them to accept a designer. We have less evidence for multi-verses than we do for design, yet scientist are willing to accept the possibility of a multi-verse but not a designer. The theories of dark matter, dark energy, and other flights of fancy are based on less evidence than that of a designer. So, the question, how many lines of evidence would it take to get a scientist to say 'I admit that the possibility of a designer is at least as good, if not better, than the possibility of random chance creating everything that exists.-I consider myself an agnostic atheist, but my views may not be typical. 
It seems pretty evident to me that the universe is largely chaotic; 
you only have to look at photos from the Hubble space telescope to see that. 
The apparent design seen in plants and animals has been adequately explained 
by Darwinian evolution and its more recent improvements.-The hypotheses of dark matter and dark energy are not yet theories on a par 
with gravity or evolution. They are on the edges of current knowledge. -The ideas of the multiversers are even more speculative in my view. Why the physical constants of the universe are what they are is unknown. I take the view that this shows we need a deeper theory than the standard model to account for their values. They are constants, not variables.-The anthropic principle, that we exist therefore the universe must be favourable for life to evolve is just a tautology. I think the universe is in large measure unsuitable for life. It is only very unusual local conditions that have allowed life to emerge on planet Earth.-The concept of anything pre-existing the universe, is just absurd. The universe is by definition everything that exists. So nothing can exist outside or before or after it. So the hypothesis of a first cause is also absurd.-The further hypothesis of a universe with inherent consciousness down to the level of its atoms or subatomic particles I find equally absurd. Consciousness is known only in higher animals and can be explained as a result of the evolution of complexity of the nervous system.

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GPJ

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George: I consider myself an agnostic atheist, but my views may not be typical. 
> It seems pretty evident to me that the universe is largely chaotic; 
> you only have to look at photos from the Hubble space telescope to see that. 
> The apparent design seen in plants and animals has been adequately explained 
> by Darwinian evolution and its more recent improvements.-We will have to agree to disagree on that. There are so many scientific objections to Evolution that it is no longer funny. Tautology and speculation to not a scientific theory make. -> 
>George: The hypotheses of dark matter and dark energy are not yet theories on a par with gravity or evolution. They are on the edges of current knowledge. -Interesting choice of words there, considering both gravity and evolution are widely accepted with little in the way of explanatory power and no direct evidence. (As opposed to the other three fundamental forces.)The weak theory of Gravity-> 
> The ideas of the multiversers are even more speculative in my view. Why the physical constants of the universe are what they are is unknown. I take the view that this shows we need a deeper theory than the standard model to account for their values. They are constants, not variables.
> -Agreed, we need a better understanding, not more speculation and science fiction as fact. -> The anthropic principle, that we exist therefore the universe must be favourable for life to evolve is just a tautology. I think the universe is in large measure unsuitable for life. It is only very unusual local conditions that have allowed life to emerge on planet Earth.
> -Agreed, not to mention it required a lot of 'just so' constants in the universe.-> The concept of anything pre-existing the universe, is just absurd. The universe is by definition everything that exists. So nothing can exist outside or before or after it. So the hypothesis of a first cause is also absurd.
> -Then all cosmology is wrong. Something can not come from nothing, and something had to exist for the Big Bang to occur. Even those physicist that wax poetic about something coming from nothing actually use tiny 'somethings' in their equations. -> The further hypothesis of a universe with inherent consciousness down to the level of its atoms or subatomic particles I find equally absurd. Consciousness is known only in higher animals and can be explained as a result of the evolution of complexity of the nervous system.-This is an ongoing matter of debate on here, and really boils down to what we consider consciousness. Further, no evolutionary theory adequately explains consciousness. If it had, much of the debate on this website would never occur. A lot of my objections to modern science do in fact stem from definitions. Scientist can't seem to simply say what they mean. The waffling on definitions to me is a sign of intellectual dishonesty. Are animals conscious, or not? Does consciousness include self-awareness, or is simple awareness enough?-Moreover, why do we defend classifications that are purely human constructs. The 'tree of life' was made up from whole-cloth and does not fit what we know now. So how can we use it to justify our claims in evolution? Which are we closer to, a monkey, a pig, or a starfish? No one knows because the categories are BS.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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The site you link to about the Weak Theory of Gravity is amusing, 
but it is intended to be satire - isn't it?

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GPJ

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George: The site you link to about the Weak Theory of Gravity is amusing, 
> but it is intended to be satire - isn't it?-Sure looks l.ike satire to me

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http://www.pbs.org/wgbh/nova/blogs/physics/2012/05/whats-the-matter-with-gravity/-
http://www.princeton.edu/~achaney/tmve/wiki100k/docs/Loop_quantum_gravity.html
Loop quantum gravity (LQG), also known as loop gravity and quantum geometry, is a proposed quantum theory of spacetime which attempts to reconcile the theories of quantum mechanics and general relativity. (This reconciliation is only needed because the theories are flawed.)-Not really. Yes, it was a humorous take on the subject, but the flaws in gravitational theory are well known and widely acknowledged.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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http://www.pbs.org/wgbh/nova/blogs/physics/2012/05/whats-the-matter-with-gravity/
> 
> 
> http://www.princeton.edu/~achaney/tmve/wiki100k/docs/Loop_quantum_gravity.html
> Loop quantum gravity (LQG), also known as loop gravity and quantum geometry, is a proposed quantum theory of spacetime which attempts to reconcile the theories of quantum mechanics and general relativity. (This reconciliation is only needed because the theories are flawed.)
> 
> Not really. Yes, it was a humorous take on the subject, but the flaws in gravitational theory are well known and widely acknowledged.-Despite Lee Smolin pushing loop quantum gravity and decrying string theory, this theory is no further along than strings, both going nowhere.

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The basic point being that our current gravity breaks down at extremely low, or extremely high levels of energy, and it can not be explained in terms of quantum mechanics like the other three fundamental forces. There is something wrong with the theory. That was all I was pointing out.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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Tony: The basic point being that our current gravity breaks down at extremely low, or extremely high levels of energy, and it can not be explained in terms of quantum mechanics like the other three fundamental forces. There is something wrong with the theory. That was all I was pointing out.-Point well taken. See my entry about black holes today.

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Tony: The basic point being that our current gravity breaks down at extremely low, or extremely high levels of energy, and it can not be explained in terms of quantum mechanics like the other three fundamental forces. There is something wrong with the theory. That was all I was pointing out.
> 
> David: Point well taken. See my entry about black holes today.-The irony of the article that you linked is that black holes, much like dark matter, dark energy, and other such theories, is that they only exist to explain away the failings of the gravitational model. -http://en.wikipedia.org/wiki/Black_hole
"The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole....Objects whose gravity fields are too strong for light to escape were first considered in the 18th century by John Michell and Pierre-Simon Laplace. The first modern solution of general relativity that would characterize a black hole was found by Karl Schwarzschild in 1916, although its interpretation as a region of space from which nothing can escape was first published by David Finkelstein in 1958. Long considered a mathematical curiosity, it was during the 1960s that theoretical work showed black holes were a generic prediction of general relativity. The discovery of neutron stars sparked interest in gravitationally collapsed compact objects as a possible astrophysical reality."-
So, if general relativity is wrong, there is no reason to even postulate the existence of black holes, dark matter, or dark energy, much less waste resources trying to figure something out that may not exist.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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> Tony: So, if general relativity is wrong, there is no reason to even postulate the existence of black holes, dark matter, or dark energy, much less waste resources trying to figure something out that may not exist.-I don't see where in your entry that general relativity is wrong. It just doesn't fit with quantum theory, which is why we have stringiness and the other bizarre theories. Try this discussion of black holes by Matt Strassler on for size:-http://profmattstrassler.com/articles-and-posts/relativity-space-astronomy-and-cosmology/black-holes/black-hole-information-paradox-an-introduction/

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> > Tony: So, if general relativity is wrong, there is no reason to even postulate the existence of black holes, dark matter, or dark energy, much less waste resources trying to figure something out that may not exist.
> 
> I don't see where in your entry that general relativity is wrong. It just doesn't fit with quantum theory, which is why we have stringiness and the other bizarre theories. Try this discussion of black holes by Matt Strassler on for size:
> 
> http://profmattstrassler.com/articles-and-posts/relativity-space-astronomy-and-cosmolog... was the article I was referring to. The problem is that the predictions of GR that predict black holes are based on the model of gravity being accurate. Like a house of cards, if you pull the cards from the bottom, the whole thing tumbles. Would GR predict black holes if redefined our understanding of Gravity? If you take away the inverse relationship between mass and gravity, then the problem of a black hole never occurs because the super dense matter is not required to generate a corresponding super-strong gravitational field. -String theory, and others, are also building upon the same wobbly foundation. Why are we wasting time and money on wild speculation before we shore up the foundation upon which all of that speculation is built upon.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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TGDaily-Physics and Astronomy. "Finding a deviation from the strong equivalence principle would indicate a breakdown of General Relativity and would point us toward a new, revised theory of gravity."-
Another example of the link between GR and Gravity

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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tony: If you take away the inverse relationship between mass and gravity, then the problem of a black hole never occurs because the super dense matter is not required to generate a corresponding super-strong gravitational field. 
> 
> String theory, and others, are also building upon the same wobbly foundation. Why are we wasting time and money on wild speculation before we shore up the foundation upon which all of that speculation is built upon.-Excellent point. How does gravity work?

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tony: If you take away the inverse relationship between mass and gravity, then the problem of a black hole never occurs because the super dense matter is not required to generate a corresponding super-strong gravitational field. 
> > 
> > String theory, and others, are also building upon the same wobbly foundation. Why are we wasting time and money on wild speculation before we shore up the foundation upon which all of that speculation is built upon.
> 
>David: Excellent point. How does gravity work?-No one knows. It is assumed to be a function of mass, but there is no physical explanation for it.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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tony: If you take away the inverse relationship between mass and gravity, then the problem of a black hole never occurs because the super dense matter is not required to generate a corresponding super-strong gravitational field. 
> > > 
> > > String theory, and others, are also building upon the same wobbly foundation. Why are we wasting time and money on wild speculation before we shore up the foundation upon which all of that speculation is built upon.
> > 
> >David: Excellent point. How does gravity work?
> 
>Tony: No one knows. It is assumed to be a function of mass, but there is no physical explanation for it.-
Actually, let me revise this statement a little. No one knows how it works. The current equations for gravity only discuss the perceived relationship between the mass of an object and the strength of its attraction to other objects.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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> Tony: Actually, let me revise this statement a little. No one knows how it works. The current equations for gravity only discuss the perceived relationship between the mass of an object and the strength of its attraction to other objects.-Back to Newton. Einstein'suggestion that a big object creates a 'valley' curvature in spacetime where things can 'roll down' to the larger object, has never made sense to me.

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Neither does the idea that an objects mass pulls on another objects mass by some invisible force that can not be directly detected. All of the other fundamental forces can be directly measured, and even manipulated to some degree, why should gravity be any different.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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Tony: Neither does the idea that an objects mass pulls on another objects mass by some invisible force that can not be directly detected. All of the other fundamental forces can be directly measured, and even manipulated to some degree, why should gravity be any different.-It is probably the key to a GUT, a grand universal theory.

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Tony: Neither does the idea that an objects mass pulls on another objects mass by some invisible force that can not be directly detected. All of the other fundamental forces can be directly measured, and even manipulated to some degree, why should gravity be any different.
> 
>David: It is probably the key to a GUT, a grand universal theory.-I agree, which is why I place so much emphasis on gaining a true understanding of it and to stop wasting time and money speculating about a model that we know to be broken.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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> >David: It is probably the key to a GUT, a grand universal theory.
> 
> Tony:I agree, which is why I place so much emphasis on gaining a true understanding of it and to stop wasting time and money speculating about a model that we know to be broken.-Because so many stringy folks have their careers wrapped up in it.

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Smaller than thought:

https://www.universetoday.com/163448/the-milky-ways-mass-is-much-lower-than-we-thought/

About 20% of previous estimates:

"One way to determine a galaxy’s mass is by looking at what’s known as its rotation curve. Measure the speed of stars in a galaxy versus their distance from the galactic center. The speed at which a star orbits is proportional to the amount of mass within its orbit, so from a galaxy’s rotation curve you can map the function of mass per radius and get a good idea of its total mass. We’ve measured the rotation curves for several nearby galaxies such as Andromeda, so we know the masses of many galaxies quite accurately.

"But since we are in the Milky Way itself, we don’t have a great view of stars throughout the galaxy. Toward the center of the galaxy, there is so much gas and dust we can’t even see stars on the far side. So instead we measure the rotation curve using neutral hydrogen, which emits faint light with a wavelength of about 21 centimeters. This isn’t as accurate as stellar measurements, but it has given us a rough idea of our galaxy’s mass. We’ve also looked at the motions of the globular clusters that orbit in the halo of the Milky Way. From these observations, our best estimate of the mass of the Milky Way is about a trillion solar masses, give or take.

"This new study is based on the third data release of the Gaia spacecraft. It contains the positions of more than 1.8 billion stars and the motions of more than 1.5 billion stars. While this is only a fraction of the estimated 100-400 billion stars in our galaxy, it is a large enough number to calculate an accurate rotation curve. Which is exactly what the team did. Their resulting rotation curve is so precise, that the team could identify what’s known as the Keplerian decline. This is the outer region of the Milky Way where stellar speeds start to drop off roughly in accordance with Kepler’s laws since almost all of the galaxy’s mass is closer to the galactic center.

"The Keplerian decline allows the team to place a clear upper limit on the mass of the Milky Way. What they found was surprising. The best fit to their data placed the mass at about 200 billion solar masses, which is a fifth of previous estimates. The absolute upper mass limit for the Milky Way is 540 billion, meaning that the Milky Way is at least half as massive as we thought. Given the amount of known regular matter in the galaxy, this means the Milky Way has significantly less dark matter than we thought."

Comment: the Milky Way is a special galaxy since it contains our Earth. Everything we learn about it points out its difference from other large galaxies. Perhaps because we are here.

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> George: The concept of anything pre-existing the universe, is just absurd. The universe is by definition everything that exists. So nothing can exist outside or before or after it. So the hypothesis of a first cause is also absurd.-I appreciate your discription of your own thought processes. but I can't let this one sit without commenting. If the universe is everything that exists, and it is without a first cause, then you are stating that the universe is eternal. What is before the Big Bang if the Big Bang created the universe? I think you must accept the proposition that you can't get something from nothing, and by this I mean true nothingness, not our spacetime with its quantum potential particles popping in and out of existence. There always has to be something to start with, and that has to be energy since what we have in our universe are forms of energy. Whether that energy is intelligent or not is the long debate dhw and I have had.

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> > George: The concept of anything pre-existing the universe, is just absurd. The universe is by definition everything that exists. So nothing can exist outside or before or after it. So the hypothesis of a first cause is also absurd.
> 
> DT: I appreciate your discription of your own thought processes. but I can't let this one sit without commenting. If the universe is everything that exists, and it is without a first cause, then you are stating that the universe is eternal. What is before the Big Bang if the Big Bang created the universe? I think you must accept the proposition that you can't get something from nothing, and by this I mean true nothingness, not our spacetime with its quantum potential particles popping in and out of existence. There always has to be something to start with, and that has to be energy since what we have in our universe are forms of energy. Whether that energy is intelligent or not is the long debate dhw and I have had.-The error in your thought processes here is not realising that time is an aspect of the universe. You are assuming the existence of infinite Newtonian (or Aristotelian?) time outside the universe. As one traces back the history of the universe from within it seems that one reaches a situation where time no longer exists, or becomes non-directional or indeterminate. That's the only solution that makes sense to me. -Since the dimensions of space also apparently contract to near zero, where length also becomes meaningless, it seems appropriate to call this initial state of the universe some form of nothingness. To attribute consciousness to it is just fanciful. It is also questionable whether it can be described in terms of energy, since energy is defined in terms of dimensions of mass, time and length.

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GPJ

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George: The error in your thought processes here is not realising that time is an aspect of the universe. You are assuming the existence of infinite Newtonian (or Aristotelian?) time outside the universe. As one traces back the history of the universe from within it seems that one reaches a situation where time no longer exists, or becomes non-directional or indeterminate. That's the only solution that makes sense to me. -I understand that time began at the Big Bang, and we live in a spacetime universe. And I also understand the Guth-Borde-Valenkin's paper at Hawking's 60th birthday says they could not find a 'before' before the Big Bang, or as they put it, 'a past incomplete'.. Further, Valenkin in the very recent past, last year, has produced a paper that states whether this is a solitary universe or a multiverse there is no 'before'. I still have a problem with something from nothing. A singularity is not a nothing. I am assuming a past without time, that has always existed.
> 
> George: Since the dimensions of space also apparently contract to near zero, where length also becomes meaningless, it seems appropriate to call this initial state of the universe some form of nothingness. To attribute consciousness to it is just fanciful. It is also questionable whether it can be described in terms of energy, since energy is defined in terms of dimensions of mass, time and length.-I would think a singularity is some form of energy and not nothingness, but an infinitely small form of energy. As for consciousness, I don't think such a commplex entity can invent itself through Darwinian evolution. I conclude it has always existed and each of us has a small part of it. I appreciate your discussion.

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George (to David): The error in your thought processes here is not realising that time is an aspect of the universe. You are assuming the existence of infinite Newtonian (or Aristotelian?) time outside the universe. As one traces back the history of the universe from within it seems that one reaches a situation where time no longer exists, or becomes non-directional or indeterminate. That's the only solution that makes sense to me. -DAVID: I understand that time began at the Big Bang, and we live in a spacetime universe. And I also understand the Guth-Borde-Valenkin's paper at Hawking's 60th birthday says they could not find a 'before' before the Big Bang, or as they put it, 'a past incomplete'.. Further, Valenkin in the very recent past, last year, has produced a paper that states whether this is a solitary universe or a multiverse there is no 'before'. I still have a problem with something from nothing. A singularity is not a nothing. I am assuming a past without time, that has always existed.-I find this discussion difficult to follow. How are you defining time? The issue for me is not time on its own but time linked to cause and effect. If the Big Bang happened, it must have had a cause. You cannot have cause and effect without before and after. No-one knows what happened or what existed before the Big Bang. If physicists can postulate unknowable multiverses in our present, why shouldn't we postulate unknowable universes or multiverses in the unknowable past? "Past" and "present" are temporal concepts, but that doesn't have to mean time as measured and experienced by us humans in our particular universe. Claims that there was no 'before' the Big Bang (= no past) are as speculative and as unprovable as claims that there are parallel Georges and Davids in parallel universes, that first cause energy is conscious of itself, and that there is an invisible teapot orbiting the sun.
 
However, I would go one step further. I find it inconceivable that the Big Bang should not have occurred without a cause, and that there was no such thing as a before (and after). Consequently, I find it inconceivable that there can ever have been pure nothingness since, as David argues, nothing can come out of nothing. This means there must have been "something" for ever and ever. And for me the most likely "something" is energy transforming itself into matter. George defines energy "in terms of dimensions of mass, time and length." Since energy can take many different forms, I wouldn't know how to define it, and I certainly wouldn't endow it with any personal qualities, but I see no reason to assume that it has not been doing whatever it does for ever and ever.

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> dhw: George defines energy "in terms of dimensions of mass, time and length." Since energy can take many different forms, I wouldn't know how to define it, and I certainly wouldn't endow it with any personal qualities, but I see no reason to assume that it has not been doing whatever it does for ever and ever.-George is a mathematician, and his definition is correct as we observe energy in our current universe.

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dhw: George defines energy "in terms of dimensions of mass, time and length." Since energy can take many different forms, I wouldn't know how to define it, and I certainly wouldn't endow it with any personal qualities, but I see no reason to assume that it has not been doing whatever it does for ever and ever.-DAVID: George is a mathematician, and his definition is correct as we observe energy in our current universe.-I am not disputing George's definition (though I don't know why mathematicians should have a monopoly on definitions). "In terms of..." covers a pretty wide area, and my point is that no matter how you wish to define it, no-one can possibly state with any authority that energy in one form of another has not been doing its own thing for ever in any number of universes past and/or present. George has attacked this idea on the grounds that one cannot assume the existence of "time" outside what he calls "the universe" and what I would prefer to call "our universe", and in tracing its history he believes "one reaches a situation where time no longer exists, or becomes non-directional or indeterminate". I have questioned how he is defining time. Specifically, if the Big Bang took place, I cannot for the life of me see how it could not have had a cause, and the sequence of cause and effect demands an onward movement from before to after, or from past to present. That is a temporal concept, and cause and effect are palpably existent, and are neither non-directional nor indeterminate. The alternative to an endless sequence of past causes and effects is a beginning without a cause and preceded by absolute nothingness. If you can believe that, you can believe anything.

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dhw: Specifically, if the Big Bang took place, I cannot for the life of me see how it could not have had a cause, and the sequence of cause and effect demands an onward movement from before to after, or from past to present. That is a temporal concept, and cause and effect are palpably existent, and are neither non-directional nor indeterminate. The alternative to an endless sequence of past causes and effects is a beginning without a cause and preceded by absolute nothingness. If you can believe that, you can believe anything.-Here, here! right on point. Leibniz asked: why is there anything? Most of us believe one cannot get something from true nothingness, excluding the non-thinkers who use spacetime with its quantum potentiality characteristic as if it is nothing! A first cause has had to always exist, and whatever it is, it must be energy, becasue only something which has the quality of energy can create a univerese made up solely of energy in whatever forms it then takes. Matter is transformed energy and visa-versa. Ask Albert. George, a response?

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DT: I am assuming a past without time, that has always existed. -A past without time makes no sense to me. It's just wordplay.-DT: As for consciousness, I don't think such a complex entity can invent itself through Darwinian evolution. I conclude it has always existed and each of us has a small part of it.-I think the complexity of consciousness is much overrated. One can clearly see stages of consciousness developing by looking at the stages of awareness to be seen in existing forms of life.-dhw: The issue for me is not time on its own but time linked to cause and effect. If the Big Bang happened, it must have had a cause. You cannot have cause and effect without before and after.-For me this is outdated thinking. Things don't need to have a cause. Things are happening all the time by chance.-dhw: "Past" and "present" are temporal concepts, but that doesn't have to mean time as measured and experienced by us humans in our particular universe.-You appear to be wanting to invent some new fantasy "time" of your own. For me it is just the ticking of a clock.-dhw: I find it inconceivable that the Big Bang should not have occurred without a cause, and that there was no such thing as a before (and after). Consequently, I find it inconceivable that there can ever have been pure nothingness since, as David argues, nothing can come out of nothing. This means there must have been "something" for ever and ever.
-It is perfectly possible to conceive such things if you really try! -I'm not arguing that the universe "came out of" nothingness (although I have considered that in the past) more that "it was" nothingness. I take the "big bang" to be the earliest stage of the universe that we can detect traces of (background radiation and all that). I suspect there was a certain amount of time and space before that for a short while, but ultimately there was no measurable time or space. I suppose that must be a type of nothingness. -I'm willing to accept that that is where logic leads me, so is the best we can say. Trying to talk about time before time and space before space is just playing with words.

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GPJ

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dhw: The issue for me is not time on its own but time linked to cause and effect. If the Big Bang happened, it must have had a cause. You cannot have cause and effect without before and after.
> 
> George: For me this is outdated thinking. Things don't need to have a cause. Things are happening all the time by chance.-But it is chance within our spacetime. How do you account for chance happening to cause a big bang, and from what?
> 
> George: You appear to be wanting to invent some new fantasy "time" of your own. For me it is just the ticking of a clock.-Time is a measured sequence, and theoretically can go in either direction, but it seems to have directionality for us.
> 
> George: I'm not arguing that the universe "came out of" nothingness (although I have considered that in the past) more that "it was" nothingness. I take the "big bang" to be the earliest stage of the universe that we can detect traces of (background radiation and all that). I suspect there was a certain amount of time and space before that for a short while, but ultimately there was no measurable time or space. I suppose that must be a type of nothingness.-I follow your thoughts, but they lead me to think again of something eternal in order to produce our something, the universe. 
> 
> George: I'm willing to accept that that is where logic leads me, so is the best we can say. Trying to talk about time before time and space before space is just playing with words.-No it isn't. There must have always been something, or you are conjuring something from a true nothing.

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I see David has replied to your post, George, but although we both ask the same fundamental question, I have a slightly different set of replies:-dhw: The issue for me is not time on its own but time linked to cause and effect. If the Big Bang happened, it must have had a cause. You cannot have cause and effect without before and after.
GEORGE: For me this is outdated thinking. Things don't need to have a cause. Things are happening all the time by chance.-Happening by chance precludes a purpose but not a cause! The rock that chanced to fall on my head did so because it was precariously balanced and because the wind blew hard at precisely the moment when I was passing by underneath it. If there chanced to be a Big Bang, what went bang and what made it go bang?
 
dhw: "Past" and "present" are temporal concepts, but that doesn't have to mean time as measured and experienced by us humans in our particular universe.
GEORGE: You appear to be wanting to invent some new fantasy "time" of your own. For me it is just the ticking of a clock.-The clock is a man-made invention geared to our human measurement of time. For me time is the onward movement from cause to effect, from past to present to future (Newtonian), and it is conceivable that in a different universe or even a different part of our own universe there could be different ways of experiencing and measuring it. Even in our own contexts, we have all experienced how in certain situations, time appears to pass more slowly/quickly.
 
GEORGE: I'm not arguing that the universe "came out of" nothingness (although I have considered that in the past) more that "it was" nothingness. I take the "big bang" to be the earliest stage of the universe that we can detect traces of (background radiation and all that). -That is clear. We do not have the means to trace anything that may have happened before the BB.-GEORGE: I suspect there was a certain amount of time and space before that for a short while, but ultimately there was no measurable time or space. I suppose that must be a type of nothingness.-But it tells us nothing about what went bang, where whatever went bang came from, and where whatever that came from, came from. Your argument appears to be that because we cannot trace anything prior to the BB, there was nothing prior to the BB except for a mysterious "short while" which presumably contained an uncaused something that hadn't existed before but went bang.
 
GEORGE: I'm willing to accept that that is where logic leads me...Trying to talk about time before time and space before space is just playing with words.-It's only playing with words because you are not prepared to consider time as a sequence of before and after, and space as something that may have existed before the BB, just as other universes may have existed before ours. I'm suggesting that there may always have been an onward flow from past to present to future (= time), and there may always have been space, and energy within space. But this whole discussion hinges on the question: If the universe "was nothingness" (no time, no space, no energy), what went bang? I'm surprised that logic leads you to say that nothing went bang.

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Your (DT and dhw) mantras that "There must have always been something" and that "Nothing can come from nothing" are where we disagree. -But we have discussed this before in the context of Victor Stenger's "Comprehensible Cosmos". -I am happy with the universe's origin being a state of "nothing" or "void" or maybe some other word is needed that doesn't have other connotations. -The "big bang" wasn't really an explosion - that was just a satirical name given to the theory by Fred Hoyle. I'm not convinced by the "inflation" aspect of the theory anyway.-The idea that there must have "always" been something betrays your inability to get the Newtonian idea of time out of your head. Time and space are measurable properties that only make sense within the universe. Once it contracts down to sub-Planck dimensions time and space have no meaning.

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GPJ

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George: Your (DT and dhw) mantras that "There must have always been something" and that "Nothing can come from nothing" are where we disagree. 
> 
> But we have discussed this before in the context of Victor Stenger's "Comprehensible Cosmos". -But Stenger does not start with nothing. He starts with a false vacuum. So he must assume it is and was eternal. And he denies fine tuning, which most every other scientist accepts.-A Stenger quote: 'Many simple systems of particles are unstable, that is, have limited lifetimes as they undergo spontaneous phase transitions to more complex structures of lower energy. Since 'nothing' is as simple as it gets, we cannot expect it to be very stable. It would likely undergo a spontaneous phase transition to something more complicated,like a universe containing matter.'- In my view this view, however, is clearly metaphysically absurd. True nothingness cannot have any properties whatsoever, including the property of instability.-> 
> George: The idea that there must have "always" been something betrays your inability to get the Newtonian idea of time out of your head. Time and space are measurable properties that only make sense within the universe. Once it contracts down to sub-Planck dimensions time and space have no meaning.- All you have stated is that Time began with the Big Bang. I agree. I have no problem with eternal timlessness until the Bang.

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DT: But Stenger does not start with nothing. He starts with a false vacuum. So he must assume it is and was eternal.-In my book "eternal" means "for all of time". 
If there is no time eternal has no meaning.-A Stenger quote: 'nothing' is as simple as it gets-With this I agree.-DT: this view, however, is clearly metaphysically absurd. True nothingness cannot have any properties whatsoever, including the property of instability.-This just shows that your concept of "true nothingness" does not exist. 
It is a metaphysical fantasy, like a perfect circle.-DT: All you have stated is that Time began with the Big Bang. I agree. I have no problem with eternal timlessness until the Bang.-As stated above I do have a problem with "eternal timelessness". 
This is an oxymoron. If there is no time there is no eternity.

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GPJ

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George: In my book "eternal" means "for all of time". 
> If there is no time eternal has no meaning.-This is where words and terms fail. My meaning is that there has always been a first cause which has existed timelessly. This is beyond our ability to describe in our words.
> 
> A Stenger quote: 'nothing' is as simple as it gets
> 
> With this I agree.
> 
> DT: this view, however, is clearly metaphysically absurd. True nothingness cannot have any properties whatsoever, including the property of instability.
> 
> George:This just shows that your concept of "true nothingness" does not exist. 
> It is a metaphysical fantasy, like a perfect circle.-Then you must agree there always has been something. I actually agree with you that there never was nothingness. We exist in something called a universe now, but it appears to have had a beginning. It was caused by something. Obviously we are all picking and choosing our own preferred cause.
> 
> DT: All you have stated is that Time began with the Big Bang. I agree. I have no problem with eternal timlessness until the Bang.
> 
> George: As stated above I do have a problem with "eternal timelessness". 
> This is an oxymoron. If there is no time there is no eternity.-In that sense you are correct. But there has always been 'something'.

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David has beaten me to it again, but I will post my answer to George as David and I don't agree on all points (especially time).-GEORGE: Your (DT and dhw) mantras that "There must have always been something" and that "Nothing can come from nothing" are where we disagree. [...] The idea that there must "always" have been something betrays your inability to get the Newtonian idea of time out of your head. Time and space are measurable properties that only make sense within the universe.-You're quite right that I can't get the Newtonian idea of time out of my mind, but that does not mean your alternative is more logical; it is the "nothing can come from nothing" mantra which suggests to me that there has to be an endless progression from past to present to future. -You believe that there has only ever been this universe, and nothing preceded it. However, in reply to David's argument that "true nothingness cannot have any properties whatsoever" you say: "This just shows that your concept of "true nothingness" does not exist. It is a metaphysical fantasy." If true nothingness does not exist, then clearly the universe did not spring from nothing but from something. And yet you claim that the universe "was nothing" before the BB. You can't have it both ways. If there is no such thing as nothing, how can the universe have been nothing? You wriggled round that earlier by saying you suspected "there was a certain amount of time and space before that for a short while". How about energy? What else could have generated the birth of the universe and its apparent expansion? And why "for a short while"? -The logical argument for "something" (eternal energy?) does not depend on Newtonian time but supports the Newtonian concept. It depends on the claim that there is no effect without a cause, and it is the sequence of cause and effect that demands a before and after, a Newtonian past and present. Whatever caused the big bang cannot have been the impossible nothing, and cannot itself have sprung into existence from the impossible nothing. We therefore have an infinite regression of cause and effect back into the past. -What happened in the past can only be a matter of speculation, but it seems feasible to me that if "something" led to our universe, the same something may have led to others prior to our 14-billion-year-old universe. This matters when we come to consider the odds against life arising by chance, so I'm surprised that you should reject the hypothesis out of hand. But my own focus is on what seems most likely, and eternal energy still seems more logical to me than the "metaphysical fantasy" of true nothingness. I don't see how the big bang would have been possible without pre-existing energy. What alternative is there?

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> dhw: What happened in the past can only be a matter of speculation, but it seems feasible to me that if "something" led to our universe, the same something may have led to others prior to our 14-billion-year-old universe. This matters when we come to consider the odds against life arising by chance, so I'm surprised that you should reject the hypothesis out of hand. But my own focus is on what seems most likely, and eternal energy still seems more logical to me than the "metaphysical fantasy" of true nothingness. I don't see how the big bang would have been possible without pre-existing energy. What alternative is there?-Let me add the thought that our spacetime is energy and only that. Stenger assumes it is eternal because he uses it to conjure up something from nothing, that is, our universe. But it is possible to conceive of pure energy without time, as the eternal source, which if it is unchanged offers no sequence to create time as we know it. I am saying that our spacetime is sequential as dhw notes. How does Stenger know what kind of anything existed before the big bang? Is our spacetime the only kind that can exist? In my view Stenger is an inept philosopher of cosmologic science.

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I have the feeling of banging my head against a wall of incomprehension here! -Nowhere does Stenger mention the origin of the universe being "eternal". -All I am doing is looking at the evidence we see within the universe and tracing it back in time. Time is a variable we measure between events, and space is a variable we measure between objects like atoms. If we trace the universe back then we get to a primordial state where neither time nor distance can be measured and therefore space-time no longer exists.-Trying to discuss this primordial state as if it existed within some extended Newtonian universe where time and space still exist seems to be where you are both going wrong. There is no "before" or "outside" to the primordial state.-Furthermore the primordial state has no mass or energy, or more precisely it has zero energy. However energy can exist in both positive and negative forms. So zero energy can be a balance of positive and negative energies. The hypothesis therefore is that some positive and negative energies by chance separated out, thus creating time and space and setting off the expansion of the primordial state to become the universe we see.

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GPJ

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George: I have the feeling of banging my head against a wall of incomprehension here!-It is my fault. I understand your points completely, but I am not explaining my philosophic approach so that you understand it. 
> 
> George Nowhere does Stenger mention the origin of the universe being "eternal".-I know that also, but from my point of view that is what his theory of origin implies, as I will explain below 
> 
> George: If we trace the universe back then we get to a primordial state where neither time nor distance can be measured and therefore space-time no longer exists.-I agree. Very logical.
> 
> George: Trying to discuss this primordial state as if it existed within some extended Newtonian universe where time and space still exist seems to be where you are both going wrong. There is no "before" or "outside" to the primordial state.-Again agreed. But something caused the primordial state.
> 
> George: Furthermore the primordial state has no mass or energy, or more precisely it has zero energy. However energy can exist in both positive and negative forms. So zero energy can be a balance of positive and negative energies. -This is where we part ways. I follow the reeasoning of Ed Feser, a philosophy professor, one of his books: The Last Superstition is on this subject of ours, which is really a discussion of cause and effect. He is a former atheist who is
now a Catholic and closely follows the reasoning of Aristotle and St. Thomas.-Nothingness is the key point. Pure nothingness is an absolute void. And the discussion has to start there. Pure nothingness is an acceptable concept. There can be such a non-existent nothing. On the other hand, as Leibniz pointed asked, why is there anything? Each effect must have a cause, but as stated by Aquinas: What does not have existence on its own must have a cause. Hume's attack on this principle of causality is entirely refuted in Feser's book.- Your description of equal amounts of positive and negative energy equalling zero is correct, but it is zero, not absolutely nothing and the whole equation is something. It represents two types of existing energy, not nothingness. I am saying there must be the total absence of energy to get rid of my insistence that something eternal has to exist. But you and Stenger use two forms of energy to create the universe. Therefore, you must accept the fact that energy (plus and minus, if you wish) has always existed. There never has been nothingness. This satisfies Liebniz' question and tells us that somehow our universe, made of energy appeared. It offers a more coherent viewpoint than we poofed out of pure nothingness. That is impossible. -And that is all I am claiming. There has always been energy, before our spacetime. It is timeless energy. I can go no further with surety. My own supposition about the attributes of that energy as a universal consciousness is my own Turell version of religion, as I left agnosticism. I think organized religion and its wishful thinking is all wet. -I hope that clarifies where my thinking leads me. And I very much appreciate your discussion with me.

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I wanted to chime in on this. The key word is nothing. No-thing. Energy is a thing. Positive energy is a thing. Negative energy is a thing. Even a void, is a thing(technically, it is a space containing no things, but you get the point..). To start any equation from no thing is automatically assuming some thing, and is therefore null and void from its conception. Without some thing, you can not add to or take away from nothing, so there had to always be some thing. -
(Yes, the removal of contractions is intentional.)

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.

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Tony: I wanted to chime in on this. The key word is nothing. No-thing. Energy is a thing. Positive energy is a thing. Negative energy is a thing. Even a void, is a thing(technically, it is a space containing no things, but you get the point..). To start any equation from no thing is automatically assuming some thing, and is therefore null and void from its conception. Without some thing, you can not add to or take away from nothing, so there had to always be some thing. 
> 
> 
> (Yes, the removal of contractions is intentional.)-This is so obvous it cannot be denied.

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George: Trying to discuss this primordial state as if it existed within some extended Newtonian universe where time and space still exist seems to be where you are both going wrong. There is no "before" or "outside" to the primordial state.-DT: Again agreed. But something caused the primordial state.-Why did something have to cause the primordial state? 
I am calling it that because it doesn't have a cause. -George: Furthermore the primordial state has no mass or energy, or more precisely it has zero energy. However energy can exist in both positive and negative forms. So zero energy can be a balance of positive and negative energies. 
 
DT: This is where we part ways. I follow the reasoning of Ed Feser, a philosophy professor, one of his books: The Last Superstition is on this subject of ours, which is really a discussion of cause and effect. He is a former atheist who is now a Catholic and closely follows the reasoning of Aristotle and St. Thomas.-Nothingness is the key point. Pure nothingness is an absolute void. And the discussion has to start there. Pure nothingness is an acceptable concept. There can be such a non-existent nothing.-To be is to exist, so you are saying here: "There can exist such a non-existent nothing" which is clearly a self-contradiction.-DT: On the other hand, as Leibniz pointed asked, why is there anything? -Perhaps because pure nothing cannot exist. Only a physical nothing - a void - can be said to exist. -Each effect must have a cause, but as stated by Aquinas: What does not have existence on its own must have a cause. Hume's attack on this principle of causality is entirely refuted in Feser's book.-In that case I'm with Hume on this. Allow me to doubt Feser's reasoning.-DT: Your description of equal amounts of positive and negative energy equalling zero is correct, but it is zero, not absolutely nothing and the whole equation is something. It represents two types of existing energy, not nothingness.-But the point is that the two types of energy do not exist until they separate out. They break the symmetry.-DT: I am saying there must be the total absence of energy to get rid of my insistence that something eternal has to exist. -Once again "eternal" means "for all time", and we are discussing a state where time does not exist. So your introduction of this concept is invalid.

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GPJ

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> David:Nothingness is the key point. Pure nothingness is an absolute void. And the discussion has to start there. Pure nothingness is an acceptable concept. There can be such a non-existent nothing.[/i]
> 
> George:To be is to exist, so you are saying here: "There can exist such a non-existent nothing" which is clearly a self-contradiction.-That is because it is difficult to find the words to fit the meaning, but you have done that below:
> 
> DT: On the other hand, as Leibniz pointed asked, why is there anything? 
> 
> George:Perhaps because pure nothing cannot exist. Only a physical nothing - a void - can be said to exist. -Exactly, a 'physical nothing' is a good way of expressing the concept.-
> 
> Each effect must have a cause, but as stated by Aquinas: What does not have existence on its own must have a cause. Hume's attack on this principle of causality is entirely refuted in Feser's book.
> 
> Geeoerge: In that case I'm with Hume on this. Allow me to doubt Feser's reasoning.-Please read Feser before doubting.
> 
> DT: Your description of equal amounts of positive and negative energy equalling zero is correct, but it is zero, not absolutely nothing and the whole equation is something. It represents two types of existing energy, not nothingness.
> 
> George:But the point is that the two types of energy do not exist until they separate out. They break the symmetry.-You are still using potential quantum effects of this space time in your theoretical approach to this. Do you really think this spacetime existed before the Big Bang?
> 
> DT: I am saying there must be the total absence of energy to get rid of my insistence that something eternal has to exist. 
> 
> George: Once again "eternal" means "for all time", and we are discussing a state where time does not exist. So your introduction of this concept is invalid.-This is just word games. I am proposing a timeless energy had to be present before the big bang, as a causative agent of the Big bang.

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GEORGE: All I am doing is looking at the evidence we see within the universe and tracing it back in time. Time is a variable we measure between events, and space is a variable we measure between objects like atoms. If we trace the universe back then we get to a primordial state where neither time nor distance can be measured and therefore space-time no longer exists.
Trying to discuss this primordial state as if it existed within some extended Newtonian universe where time and space still exist seems to be where you are both going wrong. There is no "before" or "outside" to the primordial state.-It seems to me that this is a language problem. "Primordial" means earliest, original, what existed at the beginning. And so of course you can argue that there can be nothing "before" or "outside" the beginning ... but what beginning? Each human birth is a beginning, but nobody would dream of saying nothing preceded it. The origin of life is a beginning, and we're still searching for what led to it. Why, then, should anyone assume that nothing preceded the birth of our universe? As I see it, there is simply no escaping the chain of cause and effect. You seem, with some reluctance, to have agreed that energy is indeed what came before, and so although you like to regard the universe as everything there is, the beginning of the universe was NOT the beginning of everything. It was preceded by energy:-GEORGE: Furthermore the primordial state has no mass or energy, or more precisely it has zero energy. However energy can exist in both positive and negative forms. So zero energy can be a balance of positive and negative energies. The hypothesis therefore is that some positive and negative energies by chance separated out, thus creating time and space and setting off the expansion of the primordial state to become the universe we see.-Tony and David have both answered this to the effect that in that case there has never been "nothing", but must always have been energy. Firstly, what that energy got up to during "always" nobody knows, but I see no reason why anyone should assume that throughout eternity until 14 billion years ago, energy stayed at zero. Hence the argument that ours might be only one of an endless series of universes. Secondly, I do not see how one can speak of "always" or "eternal energy" without linking it to time. "Always" entails reaching back into an endless past. That doesn't mean it has to be measurable in our human terms. May I suggest that it fits in very neatly with Newton's concept of time (irrespective of measurable events) as a constant flow from past to present to future?

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> dhw:Tony and David have both answered this to the effect that in that case there has never been "nothing", but must always have been energy. Firstly, what that energy got up to during "always" nobody knows, but I see no reason why anyone should assume that throughout eternity until 14 billion years ago, energy stayed at zero. Hence the argument that ours might be only one of an endless series of universes. Secondly, I do not see how one can speak of "always" or "eternal energy" without linking it to time. "Always" entails reaching back into an endless past. That doesn't mean it has to be measurable in our human terms. May I suggest that it fits in very neatly with Newton's concept of time (irrespective of measurable events) as a constant flow from past to present to future?-This is a very proper interpretation. Our words are inadequate to describe a concept time without time in a sequential manner, but if it always existed without change, there is no sequence of events and therefore it is timelessly eternal.

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dhw: Each human birth is a beginning, but nobody would dream of saying nothing preceded it. The origin of life is a beginning, and we're still searching for what led to it. Why, then, should anyone assume that nothing preceded the birth of our universe?-What I am saying is that the primordial state of the universe was a kind of nothingness - a void. Nothing could have preceded it because there was no time at that time! There was nothing for the nothingness to come from.-dhw: As I see it, there is simply no escaping the chain of cause and effect.-Why is there no escaping it? Only be cause it is one of your axioms.-dhw: I see no reason why anyone should assume that throughout eternity until 14 billion years ago, energy stayed at zero. -Here again you are unable to escape from your idea of Newtonian unending time.-dhw: Secondly, I do not see how one can speak of "always" or "eternal energy" without linking it to time. "Always" entails reaching back into an endless past. -It is not me that is saying this.

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GPJ

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dhw: Each human birth is a beginning, but nobody would dream of saying nothing preceded it. The origin of life is a beginning, and we're still searching for what led to it. Why, then, should anyone assume that nothing preceded the birth of our universe?-GEORGE: What I am saying is that the primordial state of the universe was a kind of nothingness - a void. Nothing could have preceded it because there was no time at that time! There was nothing for the nothingness to come from.-Let me see if I can summarize this theory. There is no such thing as "pure nothingness". The universe, which came into being some 14 billion years ago, was initially a "kind of nothingness" that consisted of positive and negative energy (which = zero energy). This chanced to separate (for no known reason) and thus produce the energy which in turn has chanced to give rise to all the materials and organisms which we now know and which never existed before because there was no before.-dhw: As I see it, there is simply no escaping the chain of cause and effect.
GEORGE: Why is there no escaping it? Only be cause it is one of your axioms.-But you have offered us a cause: the separation of positive and negative energy 14 billion years ago (if we can trust that figure). What you have not offered us is an explanation of how your "zero energy", which clearly contained the potential for the production of all the materials and organisms we now know, happened to "be". You "suspect that there was a certain amount of time and space before that [the "big bang"] for a short while." Why only for a short while? Why would primordial positive/negative energy not have existed for a long while? In fact, for ever and ever? (See the next set of comments.)-dhw: I see no reason why anyone should assume that throughout eternity until 14 billion years ago, energy stayed at zero. 
GEORGE: Here again you are unable to escape from your idea of Newtonian unending time.-Why do I need to escape from it? The argument that nothing could have preceded the universe because there was no before because there was no time seems to me to be based on nothing but assumption. Please don't misunderstand my motives here. Like yourself, I am looking for explanations I find convincing, and this whole (for me very interesting) discussion is an attempt to understand the thinking behind the different theories. I don't understand why you are so convinced that energy ... which we all seem to agree is the force that produced our universe ... did not exist until approx. 14 billion years ago. Your only answer seems to be that the Newtonian concept of time is wrong. Is it not possible in your view that positive/negative energy HAS existed for ever and ever ... as opposed to your rather mysterious "short while" ... and that the Newtonian concept of time as a constant flow from past to present to future is as valid as your own concept (which I think you have defined, though I can't locate your definition).-dhw: Secondly, I do not see how one can speak of "always" or "eternal energy" without linking it to time. "Always" entails reaching back into an endless past. 
GEORGE: It is not me that is saying this.-My apologies. This was meant to be a comment on David's acceptance of your concept of "time". It seems to me that one cannot believe in eternal energy without believing in a form of time (Newtonian) that includes an endless past.

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A new theory to copy information and thereby combine the general theory of relativity with quantum theory. Note the recognition of the need to use information which may be carried the laws we observe as we study the universe:-http://www.scientificamerican.com/article/a-meta-law-to-rule-them-all-physicists-devise-a-theory-of-everything/

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Note the author states that the Big Bang is pretty much proven in his opinion:-http://www.washingtonpost.com/blogs/achenblog/wp/2014/05/29/is-that-the-fingerprint-of-the-big-bang-or-just-foreground-dust/?wpisrc=nl%5Fpopns

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DAVID: Note the author states that the Big Bang is pretty much proven in his opinion:-http://www.washingtonpost.com/blogs/achenblog/wp/2014/05/29/is-that-the-fingerprint-of-...-Yes, OK for the BB, but now they're saying the sensational Biceps2 may have been caused by dust in the galactic foreground, so that inflation theory may yet come "into disfavor". Don't you think one should approach all these theories with just a little scepticism? With regard to "pure light" producing matter, can't we at least wait till the experiment reported in the Guardian has actually taken place?

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DAVID: Note the author states that the Big Bang is pretty much proven in his opinion:
> 
> http://www.washingtonpost.com/blogs/achenblog/wp/2014/05/29/is-that-the-fingerprint-of-... 
> Yes, OK for the BB, but now they're saying the sensational Biceps2 may have been caused by dust in the galactic foreground, so that inflation theory may yet come "into disfavor". Don't you think one should approach all these theories with just a little scepticism? With regard to "pure light" producing matter, can't we at least wait till the experiment reported in the Guardian has actually taken place?-I want you to see the controversy. I'm sure the light experiment will work. The theory from Wheeler is very solid to me. As for the B polarization, lots of experimental results will be available in about six months. I can wait. And the point I was making with the article is the idea of a BB is generally accepted despite the current skepticism about Biceps.

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http://www.nature.com/news/no-evidence-for-or-against-gravitational-waves-1.15322

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http://www.nature.com/news/big-bang-finding-challenged-1.15352

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http://www.scientificamerican.com/article/the-first-indirect-detection-of-dark-matter/?...

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Ligo. Other ways to find gravitational waves, using a distorted lazer beam:-http://www.nature.com/news/physics-wave-of-the-future-1.15561?WT.ec_id=NATURE-20140717

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Dark matter is weird:-http://news.discovery.com/space/galaxies/dark-matter-just-got-darker-and-weirder-150326.htm-"Dark matter's presence is known only by its interactions with normal matter through gravity. It does not, however, interact via the electromagnetic force, which is why we cannot directly see it  it does not emit, scatter or reflect light  it is more invisible than dark.-"In this new research, Harvey and his team realized just how invisible this stuff is, even to itself.-"As two galactic clusters collide, the stars, gas and dark matter interact in different ways. The clouds of gas suffer drag, slow down and often stop, whereas the stars zip past one another, unless they collide  which is rare. On studying what happens to dark matter during these collisions, the researchers realized that, like stars, the colliding clouds of dark matter have little effect on one another.-"Thought to be spread evenly throughout each cluster, it seems logical to assume that the clouds of dark matter would have a strong interaction  much like the colliding clouds of gas as the colliding dark matter particles should come into very close proximity. But rather than creating drag, the dark matter clouds slide through one another seamlessly.-"A previous study had seen similar behavior in the Bullet Cluster, said co-investigator Richard Massey of Durham University in the UK. But it's difficult to interpret what you're seeing if you have just one example. Each collision takes hundreds of millions of years, so in a human lifetime we only get to see one freeze-frame from a single camera angle. Now that we have studied so many more collisions, we can start to piece together the full movie and better understand what is going on.-"Now we know that dark matter particles do not experience strong frictional forces when in close proximity to other dark matter particles, their properties can be further explored. Next, the researchers want to see whether there is evidence of dark matter particles bouncing off oneanother like billiar balls. Such a kinetic interaction could display scattering properties in these vast galactic cluster collisions. They also hope to see how dark matter acts when single galaxies collide  an event that occurs more frequently than galaxy cluster collisions.-"'There are still several viable candidates for dark matter, so the game is not over, but we are getting nearer to an answer, said Harvey. These Astronomically Large' particle colliders are finally letting us glimpse the dark world all around us but just out of reach."

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Possible ways to see or find particles that represent dark matter and create gamma rays:-http://www.scientificamerican.com/article/galactic-signal-boosts-lhc-s-dark-matter-search/?WT.mc_id=SA_WR_20150506-"In 2009, Hooper and Lisa Goodenough, then a graduate student at New York University, were the first to spot the signal, in data from NASA's Fermi Gamma-Ray Space Telescope. They proposed that the bump was a signature of dark matter. Two colliding dark-matter particles would annihilate each other, just as ordinary matter does with antimatter. The annihilation would generate a succession of short-lived particles that would eventually produce ?-rays.-"But the proposed particle, which has been dubbed the hooperon or gooperon after its proponents, soon ran into problems with physicists' favourite version of supersymmetry. Although the minimal supersymmetric standard model (MSSM) allows for dark-matter particles with the estimated mass of hooperonsabout 25-30 gigaelectronvolts (1 GeV is roughly the mass of a proton)multiple experiments had suggested that the particles must be heavier. To accommodate hooperons, MSSM would have to be modified to an extent that makes many physicists uncomfortable. It would have required a completely new theory, says Sascha Caron, a particle physicist at Radboud University Nijmegen in the Netherlands, who leads the team behind the latest calculations.-*****-"Armed with this insight, Caron and his collaborators recalculated the predictions of the MSSM theory and found another potential explanation for the excessan existing dark-matter candidate called a neutralino. The neutralino was heavy enough not to be excluded by previous experiments, yet light enough to potentially be produced in the second run of the LHC.-"Caron's model also produces a prediction for the amount of dark matter that should have been created in the Big Bang that is compatible with state-of-the-art observations of the cosmic microwave backgroundthe relic radiation of the Big Bangperformed by the European Space Agency's Planck probe (see Nature http://doi.org/38k; 2014). This cannot be a coincidence, he says. I find this quite amazing.'-They might be on to something. The LHC has a chance of finding a piece of the puzzle.

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More clear skepticism:-http://www.scientificamerican.com/article/a-bold-critic-of-the-big-bang-s-smoking-gun/?&WT.mc_id=SA_DD_20140724

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Planck satellite studies say BICEPS2 probably found dust and did not prove gravitational waves. The two groups are working together now. Only Planck can do more than one frequency study which is what is needed to completely clear this up:-http://www.scientificamerican.com/article/betting-against-gravitational-waves-neil-turok/?WT.mc_id=SA_SPC_20140925-Also:-http://www.scientificamerican.com/article/gravitational-wave-discovery-looks-doubtful-in-new-analysis/?WT.mc_id=SA_SPC_20140925

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More discussion of BICEPS2, inflation gravitational waves, multiverses, cyclical universes, and on and on, with nothing certain:-http://www.newscientist.com/article/dn26272-cosmic-inflation-is-dead-long-live-cosmic-inflation.html?full=true

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A new paper, not peer reviewed says there are no black holes:-
"In 1974, Stephen Hawking used quantum mechanics to show that black holes emit radiation. Since then, scientists have detected fingerprints in the cosmos that are consistent with this radiation, identifying an ever-increasing list of the universe's black holes.
 
"But now Mersini-Houghton describes an entirely new scenario. She and Hawking both agree that as a star collapses under its own gravity, it produces Hawking radiation. However, in her new work, Mersini-Houghton shows that by giving off this radiation, the star also sheds mass. So much so that as it shrinks it no longer has the density to become a black hole.
 
"Before a black hole can form, the dying star swells one last time and then explodes. A singularity never forms and neither does an event horizon. The take home message of her work is clear: there is no such thing as a black hole."-
 Read more at: http://phys.org/news/2014-09-black-holes.html#jCp

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There is another method to study CMB polarization than Biceps2, fully discussed in this article, as well as the Planck satellite findings:-http://phys.org/news/2014-10-polarbear-cosmic-microwave-polarization.html-"The POLARBEAR team, which uses microwave detectors mounted on the Huan Tran Telescope in Chile's Atacama Desert, consists of more than 70 researchers from around the world. They submitted their new paper to the journal one week before the surprising March 17 announcement by a rival group, the BICEP2 (Background Imaging of Cosmic Extragalactic Polarization) experiment, that they had found the holy grail of microwave background research. That team reported finding the signature of cosmic inflation - a rapid ballooning of the universe when it was a fraction of a fraction of a second old - in the polarization pattern of the microwave background radiation.
 
"Subsequent observations, such as those announced last month by the Planck satellite, have since thrown cold water on the BICEP2 results, suggesting that they did not detect what they claimed to detect.
 
"While POLARBEAR may eventually confirm or refute the BICEP2 results, so far it has focused on interpreting the polarization pattern of the microwave background to map the distribution of matter back in time to the universe's inflationary period, 380,000 years after the Big Bang."

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Multiverse or no multiverse? Physicists musing and speculating with nothing provable:-http://www.quantamagazine.org/20141103-in-a-multiverse-what-are-the-odds/

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Peter Woit musings on multiverse foolishness. It seems to require some fine tuning also, and it is not falsifiable:-http://www.math.columbia.edu/~woit/wordpress/

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He doubts inflation and multiverse as non-answers. Still hopes superstring theory might work, but admits 30 years of almost no progress.:-http://blogs.scientificamerican.com/cross-check/2014/12/01/physicist-paul-steinhardt-slams-inflation-cosmic-theory-he-helped-conceive/-
"I have to admit that I did not take the multiverse problem seriously at first even though I had been involved in uncovering it. I thought someone would figure out a resolution once the problem was revealed. That was 1983. I was wrong. Unfortunately, what has happened since is that all attempts to resolve the multiverse problem have failed and, in the process, it has become clear that the problem is much stickier than originally imagined. In fact, at this point, some proponents of inflation have suggested that there can be no solution. We should cease bothering to look for one. Instead, we should simply take inflation and the multiverse as fact and accept the notion that the features of the observable universe are accidental: consequences of living in this particular region of the multiverse rather than another.-"To me, the accidental universe idea is scientifically meaningless because it explains nothing and predicts nothing. Also, it misses the most salient fact we have learned about large-scale structure of the universe: its extraordinary simplicity when averaged over large scales. In order to explain the one simple universe we can see, the inflationary multiverse and accidental universe hypotheses posit an infinite variety of universes with arbitrary amounts of complexity that we cannot see. Variations on the accidental universe, such as those employing the anthropic principle, do nothing to help the situation.-"Scientific ideas should be simple, explanatory, predictive. The inflationary multiverse as currently understood appears to have none of those properties.-"These concerns and more, and the fact that we have made no progress in 30 years in addressing them, are what have made me skeptical about the inflationary picture."

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DAVID: He doubts inflation and multiverse as non-answers. Still hopes superstring theory might work, but admits 30 years of almost no progress.:-http://blogs.scientificamerican.com/cross-check/2014/12/01/physicist-paul-steinhardt-sl...-Thank you for a wonderfully refreshing article, which basically boils down to the fact that nobody has a clue about the true nature of the universe. I was particularly struck by two passages, the first of which bothers me somewhat, while the second made me laugh out loud with admiration and approval:-1) Scientific ideas should be simple, explanatory, predictive. The inflationary multiverse as currently understood appears to have none of those properties."-I don't know why scientific ideas should be simple. It's pretty clear from all these unsatisfactory theories that the universe and life itself are far from simple. Quantum theory emphasizes the point. And why should scientific ideas be predictive if the reality they are meant to explain is unpredictable?
 
2) Horgan: In the 1980s, Stephen Hawking suggested that physics might someday provide such satisfying answers that the field would end. Do you - or did you ever - share this hope?
Steinhardt: No. I tend to feel that every answer generates more questions, and my hope is that this continues.
Horgan: Are you religious? Can you be a physicist and also believe in God?
Steinhardt: I never answer the first question because I consider religion to be a private matter. My scientific views stand on their own and I would like them to be evaluated independent of my private views about religion.
In answer to your second question, it is a demonstrated fact that successful physicists can believe in God.-Three answers that bring joy to my agnostic heart!

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dhw: Three answers that bring joy to my agnostic heart!-Steinhardt has been one of my favorite physicists, not because of his cyclical universe membrane-banging theory of years ago, which seemed weird to me, but his honesty about where we really are at this point in our knowledge, which is a giant pause in major understandings for over 30+ years. Another is Matt Strassler, an advisor to the LHC, who also gives careful thought to what is currently happening without presenting outrageous possibilities like Stephan Hawking has been doing.

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Peter Woit, who thinks multiverse proposals are garbage puts in his oar:-http://www.math.columbia.edu/~woit/wordpress/?p=7385-"The Guardian has a podcast up today featuring Robert Trotta and David Wallace called The Multiverse in a Nutshell. It's largely more of the usual uncritical multiverse hype that has been flooding the public expositions of fundamental physics for years now. Trotta gives the usual promotion of the cosmological multiverse, with no indication there is any problem with it. He assures us that this is being tested (by looking for bruises in CMB collisions). As far as I can tell, the Planck results released today, like all CMB data, show no evidence for anything like this. It appears that the Planck people don't even think this is worth mentioning. The public channels used for this hype will never report the fact that there's nothing there, instead they will just endlessly talk about this as something scientists are looking for.'"

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If time was faster in the past and slower now, the need to postulate dark energy disappears:-
""The accelerated expansion of the universe has been attributed to the effects of dark energy," Kipreos said. "However, there is no understanding of what dark energy is or why it has manifested only recently.-"The predicted effects of time being faster in the past would have the effect of making the plot of supernovas become linear at all distances, which would imply that there is no acceleration in the expansion of the universe. In this scenario there would be no necessity to invoke the existence of dark energy."-
 Read more at: http://phys.org/news/2014-12-alternative-explanation-dark-energy.html#jCp

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It turns out there are two types of super novae. This means the expansion rate may be slower and must be recalculated:-http://www.eurekalert.org/pub_releases/2015-04/uoa-aun041015.php-"Certain types of supernovae, or exploding stars, are more diverse than previously thought, a University of Arizona-led team of astronomers has discovered. The results, reported in two papers published in the Astrophysical Journal, have implications for big cosmological questions, such as how fast the universe has been expanding since the Big Bang. -"Most importantly, the findings hint at the possibility that the acceleration of the expansion of the universe might not be quite as fast as textbooks say. -"The team, led by UA astronomer Peter A. Milne, discovered that type Ia supernovae, which have been considered so uniform that cosmologists have used them as cosmic "beacons" to plumb the depths of the universe, actually fall into different populations. The findings are analogous to sampling a selection of 100-watt light bulbs at the hardware store and discovering that they vary in brightness. -"'We found that the differences are not random, but lead to separating Ia supernovae into two groups, where the group that is in the minority near us are in the majority at large distances -- and thus when the universe was younger," said Milne, an associate astronomer with the UA's Department of Astronomy and Steward Observatory. "There are different populations out there, and they have not been recognized. The big assumption has been that as you go from near to far, type Ia supernovae are the same. That doesn't appear to be the case." -"The discovery casts new light on the currently accepted view of the universe expanding at a faster and faster rate, pulled apart by a poorly understood force called dark energy. This view is based on observations that resulted in the 2011 Nobel Prize for Physics awarded to three scientists, including UA alumnus Brian P. Schmidt."

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A new theory says the universe has sped up and slowed down seven times:-http://phys.org/news/2015-06-universe-crystal-glass.html-"'Then in 1998 the finding that the universe was not only expanding, but was speeding up, or accelerating in its expansion was a shock when it was discovered simultaneously by east coast and west coast teams of astronomers and physicists," said Mead. "A new form of matter, dark energy, repulsive in nature, was responsible for the speed-up. The teams led by Saul Perlmutter, Adam Riess, and Brian Schmidt won the 2011 Nobel Prize in Physics for that discovery.'"-"According to Mead and Ringermacher, this change from slowing down to speeding up (the transition time) took place approximately 6 to 7 billion years ago. Since then, Mead and Ringermacher say a vast accumulation of high-tech data has verified the theory to extraordinary accuracy.-****-"'The new finding suggests that the universe has slowed down and speeded up, not just once, but 7 times in the last 13.8 billion years, on average emulating dark matter in the process," said Mead. "The ringing has been decaying and is now very small - much like striking a crystal glass and hearing it ring down.'"

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Biceps2 is definitely wrong. No gravitational waves found as yet. Planck satellite settled the issue. It doesn't mean the waves don't exist, there are suspicious signs in the data.:-http://www.nytimes.com/2015/01/31/us/a-speck-of-interstellar-dust-rebuts-a-big-bang-theory.html?emc=edit_th_20150131&nl=todaysheadlines&nlid=60788861&_r=0-"The Bicep/Planck analysis was led by Dr. Pryke, one of the four Bicep principal investigators. Brendan Crill, of the California Institute of Technology and a member of Planck, acted as a liaison between the groups. They had planned to post their paper Monday, but the data was posted early, apparently by accident. It was soon taken down, but not before it set off an outburst of Twitter messages and hasty news releases.-"A paper is to be posted to the Bicep website and has been submitted to the journal Physical Review Letters.-"But it will be far from the final word. A flotilla of experiments devoted to the cause are underway, studying a thin haze of microwaves, known as cosmic background radiation, left from the Big Bang, when the cosmos was about 380,000 years old. Among them is a sister experiment to Bicep called Spider, led by Bill Jones of Princeton and involving a balloon-borne telescope that just completed a trip around Antarctica, as well as Bicep's own Keck Array and the recently installed Bicep3.-"At stake is an idea that has galvanized cosmologists since Alan Guth of the Massachusetts Institute of Technology invented it in 1979. Inflation theory holds that the universe had a violent and brief surge of expansion in the earliest moments, driven by a mysterious force field that exerted negative gravity. It would explain such things as why the universe looks so uniform and where galaxies come from  quantum dents in the inflating cosmos."-Another version of the story:-http://phys.org/news/2015-01-planck-gravitational-elusive.html

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We seem to know a great deal about black holes without ever being to one:-"In a new paper, physicists Ahmed Farag Ali, Mir Faizal, and Barun Majunder have shown that, according to a new generalization of Einstein's theory of gravity called "gravity's rainbow," it is not possible to define the position of the event horizon with arbitrary precision. If the event horizon can't be defined, then the black hole itself effectively does not exist.-"In gravity's rainbow, space does not exist below a certain minimum length, and time does not exist below a certain minimum time interval," Ali, a physicist at the Zewail City of Science and Technology and Benha University, both in Egypt, told Phys.org. "So, all objects existing in space and occurring at a time do not exist below that length and time interval [which are associated with the Planck scale]. As the event horizon is a place in space which exists at a point in time, it also does not exist below that scale."-"The most important lesson from this paper is that space and time exist only beyond a certain scale," Ali concluded. "There is no space and time below that scale. Hence, it is meaningless to define particles, matter, or any object, including black holes, that exist in space and time below that scale. Thus, as long as we keep ourselves confined to the scales at which both space and time exist, we get sensible physical answers. However, when we try to ask questions at length and time intervals that are below the scales at which space and time exist, we end up getting paradoxes and problems."- Read more at: http://phys.org/news/2015-01-black-holes-space-theory.html#jCp-Whew!

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Changes the sequence of star development to over 140 million years later. Requires new exotic physics to explain:-:It was hoped that Planck might find direct evidence in the CMB's polarisation for inflation - the super-rapid expansion of space thought to have occurred just fractions of a second after the Big Bang. This has not been possible. But all the Planck data - temperature and polarisation information - is consistent with that theory, and the precision measurements mean new, tighter constraints have been put on the likely scale of the inflation signal, which other experiments continue to chase.-"What is clear from the Planck investigation is that the simplest models for how the super-rapid expansion might have worked are probably no longer tenable, suggesting some exotic physics will eventually be needed to explain it.-"'We're now being pushed into a parameter space we didn't expect to be in," said collaboration scientist Dr Andrew Jaffe from Imperial College, UK. "That's OK. We like interesting physics; that's why we're physicists, so there's no problem with that. It's just we had this naïve expectation that the simplest answer would be right, and sometimes it just isn't.'"-http://www.bbc.com/news/science-environment-31145520

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The folks won't give u. bicep 3 is about to reach the end of more data:-http://www.washingtonpost.com/blogs/achenblog/wp/2015/03/17/a-year-later-bicep2-astronomer-upbeat-as-he-hunts-for-elusive-big-bang-signal/?wpisrc=nl_popns&wpmm=1-"We're very far along in the next analysis of the next data set. It's going to be much more powerful, Kovac told me.-"This is a man who has devoted his professional life to South Pole astronomy, making 24 trips there, each as arduous as you can imagine (fly to New Zealand, then to the McMurdo station on the Antarctica coast, then to the South Pole). In his early 20s, he overwintered at the South Pole, spending 14 months straight at the bottom of the world. In the early 1990s, South Pole astronomer was a much more rugged affair with primitive equipment and a lot of exposure to the elements. He showed me a photograph in which, dressed almost like an astronaut, he's climbing onto a telescope with a giant tank of liquid helium on his back. This kind of astronomy requires very cold instruments, which is why he has spent two decades lugging liquid helium to the South Pole. As he puts it, the South Pole just isn't cold enough by itself.-"It's safe to say that if Kovac and his colleagues can't detect the signal of cosmic inflation, it won't be for lack of trying.-"I asked if the new observations will tell us whether there really are cosmological signals in the CMB, or just polarization generated by dust.-"'That's going to depend on what the universe has to say, he said. The power of our data is going to keep getting better.'"

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Matt Strassler covered this yesterday on his blog, but I didn't post it, as too technically advanced. This article is simpler and what is found is a blip by two methods off the curve created by a collision of protons. It is heavier than Higgs.-http://www.scientificamerican.com/article/potential-new-particle-shows-up-at-the-lhc-thrilling-and-confounding-physicists1/?WT.mc_id=SA_DD_20151217-"A little wiggle on a graph, representing just a handful of particles, has set the world of physics abuzz. Scientists at the Large Hadron Collider (LHC) in Switzerland, the largest particle accelerator on Earth, reported yesterday that their machine might have produced a brand new particle not included in the established laws of particle physics known as the Standard Model. Their results, based on the data collected from April to November after the LHC began colliding protons at nearly twice the energy of its previous runs, are too inconclusive to be suremany physicists warned that the wiggle could just as easily represent a statistical fluke. Nevertheless, the finding has already spawned at least 10 new papers in less than a day proposing a theoretical explanation for the particle, and has the halls and blackboards of physics departments around the world churning.-'This is something that we've been waiting for for a long time, says Adam Falkowski, a physicist at the Institute of Theoretical Physics in Warsaw and a member of the CERN Theory Group. Of course we are aware this could be nothing. But for my generation, this is the first time there is a very large, quite reliable signal of physics beyond the Standard Model, so it's definitely very exciting. Of course, others echoed the usual refrain of caution: Extraordinary claims require extraordinary evidence, and this is not that, Columbia University physicist Peter Woit wrote on his blog."-Comment: If this is real it is beyond the standard Model which ended with Higgs.

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A new paper from Hawking states not all information is lost in a black hole:-http://blogs.scientificamerican.com/dark-star-diaries/stephen-hawking-s-new-black-hole-paper-translated-an-interview-with-co-author-andrew-strominger/?WT.mc_id=SA_DD_20160108-"Now the details are hereat least some of them. This week Hawking, the University of Cambridge physicist Malcolm J. Perry, and the Harvard University string theorist Andrew Strominger posted a paper online in which the authors claim to make real progress toward solving the black-hole information paradox. Despite the inviting titleSoft Hair on Black Holesthe paper is mercilessly technical, so I asked Strominger to walk me through it. An edited transcript of our conversation follows."-Comment; A very complex discussion. I suggest reading the interview.

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A new article on this possible new heavy particle:-http://www.nature.com/news/who-ordered-that-1.19514?WT.ec_id=NATURE-20160310&spMailingID=50877899&spUserID=MjA1NjE2NDU5MwS2&spJobID=881159065&spReportId=ODgxMTU5MDY1S0-"If the particle exists, the implications would be enormous. Precisely because it is so unexpected, it could be the most important discovery in particle physics since quarks  the elementary constituents of protons and neutrons  were confirmed to exist in the 1970s. Perhaps it would be the biggest deal since the muon itself.-"The evidence so far is scant, however. It amounts to a few too many pairs of ?-ray photons produced with combined energies of 750 gigaelectronvolts when the LHC smashes protons together. The fact that two separate detectors spotted it at almost exactly the same energies gives some hope, but anomalous signals such as this often show up in experiments only to later vanish back into the noisy background.-"Still, people at CERN, the European particle-physics lab that hosts the LHC, have scarcely talked about anything else since. And theoretical physicists around the world have gone into overdrive: more than 200 papers have been posted online with theories that could explain the particle. One possibility is that it could be a heavier cousin of the Higgs boson; another, even more tantalizing one, is that it is a type of graviton, the particle hypothesized to carry the force of gravity. If so, it could point to the existence of extra dimensions of space beyond the familiar three.-***-"The current generation of young physicists was not even born when particle accelerators produced their last genuinely surprising results. Meanwhile, searches for physics beyond the standard model have so far come up empty  at accelerators such as the LHC but also in many tabletop experiments and at detectors built underground or sent into space to look for dark matter. The most notable exception to the standard model's standard fare has been the discovery, beginning in 1998, that the elementary particles called neutrinos spontaneously oscillate between their three known types, or flavours  something that the original version of the standard model had not predicted. That breakthrough earned two physicists a well-deserved Nobel Prize last year.-"The LHC is now providing the opportunity of a lifetime to break entirely new ground. In 2015, it restarted after a long shutdown that brought the energies of its collisions to a record 13 teraelectronvolts, from 8 TeV. This has put much more massive particles in reach  if any exist  but it will be the last substantial jump in collider energies in a generation. More-powerful machines, if they ever see the light of the day, will take decades to plan, develop and build.-"The good news is that whether the new particle exists or the data bump is a statistical anomaly is not a question that will leave us hanging for long. The LHC experiments had time to observe only relatively few collisions in their first 13 TeV run last year, before the experiment shut down for its winter recess."-Comment: We'll have to wait.

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The LHC is about to go back to work after maintenance and upgrades. The hint of a new particle stirs expectations of a breakthrough and this article describes what might be happening. The standard model is not really complete and has many questions, especially what is dark matter?: - https://aeon.co/opinions/physics-is-on-the-verge-of-an-earth-shattering-discovery?utm_s... - "The Higgs boson filled in the last missing piece of the Standard Model, but this model is itself clearly incomplete. None of its particles has the properties of dark matter, a mysterious entity that is five times as prevalent as all the ordinary matter (everything made of atoms, which in turn are built from quarks and electrons) visible in the stars and galaxies. The Standard Model also does not explain the wide range of masses of the fundamental particles, nor why antimatter seems to have nearly completely disappeared, leaving the Universe filled almost exclusively with matter. - "That is why, after spending nearly 60 years building the Standard Model, particle physicists are now terribly excited at the prospect of finally breaking it. The flaws of the model were well known, but no one knows what the right model might be. - *** - "For the first time last year, the LHC produced collisions with an energy of 13 trillion electron volts (TeV), far above the 8 TeV it had achieved before. If new particles exist - beyond the known ones comprised within the Standard Model - that energy upgrade potentially brought them within reach. Given the technical difficulties associated with raising the LHC's operating energy, the data sample accumulated in 2015 was small. Hence, the researchers found just a handful of unusual events. The presence of a new particle can only be confirmed with more data, which should be available by this summer. - "Massive particles are unstable and break down so rapidly that all physicists can see is the trail of secondary decay particles they leave behind. It this case, the trail was an intriguing excess of events containing two photons with a combined mass of 750 billion electron volts (GeV); that is, these pairs of photons all seemed to emerge from an unknown particle six times as massive as the Higgs boson and 800 times the mass of a proton. - *** - "Any new particle or phenomenon that advances physics toward such a grand theory would be more Earth-shattering than the discovery of the Higgs boson or the recent detection of gravitational waves. Both of those had been predicted for many years; finding them was an experimental triumph, but it merely confirmed what was already theoretically understood, and did not deepen our fundamental comprehension of the Universe." - Comment: It has been stated that to fully understand the Big Bang we need an LHC the size of the universe, but it did give us the fine tuning we needed to appear.

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This article describes the history of the standard model, and explains why there is no grand unified model. Gravity is one of the outliers':-http://www.symmetrymagazine.org/article/a-gut-feeling-about-physics-"While that Standard Model is a very good description of the subatomic world, some important aspectssuch as particle massescome out of experiments rather than theory.-'If you write down the Standard Model, quite frankly it's a mess, says John Ellis, a particle physicist at King's College London. You've got a whole bunch of parameters, and they all look arbitrary. You can't convince me that's the final theory!-"The hunt was on to create a grand unified theory, or GUT, that would elegantly explain how the universe works by linking three of the four known forces together. Physicists first linked the electromagnetic force, which dictates the structure of atoms and the behavior of light, and the weak nuclear force, which underlies how particles decay.-"But they didn't want to stop there. Scientists began working to link this electroweak theory with the strong force, which binds quarks together into things like the protons and neutrons in our atoms. (The fourth force that we know, gravity, doesn't have a complete working quantum theory, so it's relegated to the realm of Theories of Everything, or ToEs.)-***-"GUTs also predicted that protons should decay into lighter particles. There was just one problem: Experiments didn't see that decay.-"GUTs predicted that all quarks could potentially change into lighter particles, including the quarks making up protons. In fact, GUTs said that protons would be unstable over a period much longer than the lifetime of the universe. To maximize the chances of seeing that rare proton decay, physicists needed to build detectors with a lot of atoms.-"However, the first Kamiokande experiment in Japan didn't detect any proton decays, which meant a proton lifetime longer than that predicted by the simplest GUT theory. More complicated GUTs emerged with longer predicted proton lifetimes - and more complicated interactions and additional particles.-***-"Most modern GUTs mix in supersymmetry (SUSY), a way of thinking about the structure of space-time that has profound implications for particle physics. SUSY uses extra interactions to adjust the strength of the three forces in the Standard Model so that they meet at a very high energy known as the GUT scale.-'Supersymmetry gives more particles that are involved via virtual quantum effects in the decay of the proton, says JoAnne Hewett, a physicist at the Department of Energy's SLAC National Accelerator Laboratory. That extends the predicted lifetime of the proton beyond what previous experiments were able to test. Yet SUSY-based GUTs also have some problems.-
***-"Hewett agrees that GUTs aren't dead yet.-'I firmly believe that an observation of proton decay would affect how every person would think about the world, she says. Everybody can understand that we're made out of protons and Oh wow! They decay.'-"Upcoming experiments like the proposed Hyper-K in Japan and the Deep Underground Neutrino Experiment in the United States will probe proton decay to greater precision than ever. Seeing a proton decay will tell us something about the unification of the forces of nature and whether we ultimately can trust our GUTs."-Comment: Gravity and quantum theory don't fit. Look at article to read more and see diagrams, but they are still trying. Note empirical data is necessary for all theories.

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The magnetic field of the sun and of the Earth connect, disconnect and reconnect releasing huge amounts of energy, a group of satellites has found:-https://www.sciencedaily.com/releases/2016/05/160512145509.htm-"Physicists have now provided the first major results of NASA's Magnetospheric Multiscale (MMS) mission, including an unprecedented look at the interaction between the magnetic fields of Earth and the sun. The article describes the first direct and detailed observation of a phenomenon known as magnetic reconnection, which occurs when two opposing magnetic field lines break and reconnect with each other, releasing massive amounts of energy. -"Most people do not give much thought to the Earth's magnetic field, yet it is every bit as essential to life as air, water and sunlight. The magnetic field provides an invisible, but crucial, barrier that protects Earth from the sun's magnetic field, which drives a stream of charged particles known as the solar wind outward from the sun's outer layers. The interaction between these two magnetic fields can cause explosive storms in the space near Earth, which can knock out satellites and cause problems here on Earth's surface, despite the protection offered by Earth's magnetic field.-***-"Evidence suggests that reconnection is a major driving force behind events such as solar flares, coronal mass ejections, magnetic storms, and the auroras observed at both the North and South poles of Earth. Although researchers have tried to study reconnection in the lab and in space for nearly half a century, the MMS mission is the first to directly observe how reconnection happens.-"The MMS mission provided more precise observations than ever before. Flying in a pyramid formation at the edge of Earth's magnetic field with as little as 10 kilometers' distance between four identical spacecraft, MMS images electrons within the pyramid once every 30 milliseconds. In contrast, MMS' predecessor, the European Space Agency and NASA's Cluster II mission, takes measurements once every three seconds--enough time for MMS to make 100 measurements.-***-"A clearer picture of the physics of reconnection will also bring us one step closer to understanding space weather--including whether solar flares and magnetic storms follow any sort of predictable pattern like weather here on Earth. Reconnection can also help scientists understand other, more energetic astrophysical phenomena such as magnetars, which are neutron stars with an unusually strong magnetic field.-***-"'Reconnection in Earth's magnetic field is relatively low energy, but we can get a good sense of what is happening if we extrapolate to more energetic systems," Swisdak added. "The edge of Earth's magnetic field is an excellent test lab, as it's just about the only place where we can fly a spacecraft directly through a region where reconnection occurs."-"To date, MMS has focused only on the sun-facing side of Earth's magnetic field. In the future, the mission is slated to fly to the opposite side to investigate the teardrop-shaped tail of the magnetic field that faces away from the sun."-Comment: Amazing what our satellites can study. Note how carefully protected is the Earth. God's work?

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A recent study of supernovas and Cepheid stars thinks the expansion rate is faster than originally measured. This is a change in the measured Hubble constant:-http://www.scientificamerican.com/article/the-universe-may-be-expanding-faster-than-astronomers-thought/?WT.mc_id=SA_DD_20160603 -"The universe is expanding 5 to 9 percent faster than astronomers had thought, a new study suggests.-"'This surprising finding may be an important clue to understanding those mysterious parts of the universe that make up 95 percent of everything and don't emit light, such as dark energy, dark matter and dark radiation," study leader Adam Riess, an astrophysicist at the Space Telescope Science Institute and Johns Hopkins University in Baltimore, said in a statement.-"Riesswho shared the 2011 Nobel Prize in physics for the discovery that the universe's expansion is acceleratingand his colleagues used NASA's Hubble Space Telescope to study 2,400 Cepheid stars and 300 Type Ia supernovas. [Supernova Photos: Great Images of Star Explosions]-"These are two different types of "cosmic yardsticks" that allow scientists to measure distances across the universe. Cepheids pulse at rates that are related to their true brightness, and Type Ia supernovaspowerful explosions that mark the deaths of massive starsblaze up with consistent luminosity.-"This work allowed the team to determine the distances to the 300 supernovas, which lie in a number of different galaxies. Then, the researchers compared these figures to the expansion of space, which was calculated by measuring how light from faraway galaxies stretches as it moves away from Earth, to determine how fast the universe is expandinga value known as the Hubble constant, after famed American astronomer Edwin Hubble.-"The new, unprecedentedly precise value for the Hubble constant comes out to 45.5 miles (73.2 kilometers) per second per megaparsec. (One megaparsec is equivalent to 3.26 million light-years.) Therefore, the distance between cosmic objects should double 9.8 billion years from now, the researchers said.-***-" The mysterious force known as dark energy, which is thought to be behind the universe's accelerating expansion, may be stronger than astronomers had thought. It's also possible that "dark radiation"an unknown, superspeedy subatomic particle or particles that existed shortly after the Big Bangcould be playing a role that hasn't been taken into account, the researchers said.-"Enigmatic dark matter, which is thought to be four times more abundant than "normal" matter throughout the universe, could also have some weird and unappreciated characteristics. Or maybe there's something important missing from Einstein's theory of gravity, the researchers said.-***-""We know so little about the dark parts of the universe; it's important to measure how they push and pull on space over cosmic history," study co-author Lucas Macri, of Texas A&M University, said in the same statement."-Comment: We still just a little about our universe.

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A scholarly review of the problem:

http://nautil.us//blog/the-quest-for-unity-is-not-something-physics-is-cut-out-to-do?ut...

"In physics, we like theories that are simple and broad-ranging. By “simple,” physicists usually mean a mathematical theory that rests on as few postulates as possible; by “broad-ranging,” we mean theories that can describe a wide class of phenomena, even when apparently not related. A quintessential example is Einstein’s theory of general relativity. Resting on a handful of simple principles, it successfully describes planetary orbits in this (and any) solar system, black holes, gravitational waves, and the expansion of the universe.

***

"beautiful theories have a mathematical integrity that seems to be revealing something deep about nature, a sort of hidden code of Creation: From the very large to the very small, the universe has many layers, each built upon its own mathematical description. Are these not parts of a larger composition, a single unifying tune resonating through all of nature?

***

" But today we are seeing the limits of this Platonic thrust to mathematize nature, due to a lack of experimental validation and several theoretical obstacles—including the possibility of multiple universes and the troubling questions they pose.

"The modern version of the unifying quest is string theory, which supposes that the fundamental entities in nature are vibrating tubes of energy instead of point-like particles of matter.

***

"Fast-forward three decades, and the scenario has changed dramatically. Physicists were shocked to find, instead of a single solution, a huge number of solutions—by some estimates, a 1 followed by 500 zeros, each a different twist in the extra-dimensional space, each generating a different universe. Presumably, each one of these has its own set of fundamental constants, numbers such as the electron’s mass and charge and the strength of the gravitational attraction, which determine nature’s physical properties. Where’s our universe among such vast number of possibilities? We do know that if we tweaked such constants by very small amounts, life wouldn’t be possible: We wouldn’t be here. In other words, we live where we live because we couldn’t live anywhere else—our universe is one of the few that allows for our existence. True enough, but as a scientific argument this buys us very little. Worse, it sounds tautological. String theory went from being the theory that would mathematically prove the uniqueness of our universe to a theory that allows a countless number of possible universes, none more compelling than the other.

***

"The problem is rooted in a much deeper philosophical issue, that of the First Cause. Being creatures immersed in the passage of time, with a clear beginning and an end, humans have been forever dumbfounded by initial conditions. How could something come out of nothing? And what sets the properties of this something (read “values of fundamental constants”) at the beginning? Who ordered that? Who ordered us?"

Our mistake is that, within a scientific context, these are the wrong questions to ask.

Physics works under a very clear framework. In order to determine the time evolution of a system, we need to state its initial conditions, the state of the system at time zero. This implies knowledge of the system at the beginning, something we obtain through measurement. In cosmology, that becomes impossible. We may restrict the initial conditions and the values of the fundamental constants given what we know about the universe today, but we can’t be sure that our conclusions are in any way final. The clues we gather today about the universe’s distant past can only give us a fragmented picture of what happened. The multiverse only pushes the issue of initial conditions to a higher level, without solving it.

***

" Maybe our current dilemma is a symptom of something bigger, a deep change in the methodological nature of physical theories. We may have to see them historically, tossing aside First Cause explanations and timeless truths as fruitless pursuits. Quite possibly, the nature of physical theories mirrors their own narrative construction, piecewise and gradual, creations of our imperfect and incomplete grasp on physical reality. And there’s nothing wrong with that."

Comment: One simple solution is to accept God as the First Cause. String theory is obviously dead snd no other is apparently on the way.

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QUOTE: “Maybe our current dilemma is a symptom of something bigger, a deep change in the methodological nature of physical theories. We may have to see them historically, tossing aside First Cause explanations and timeless truths as fruitless pursuits. Quite possibly, the nature of physical theories mirrors their own narrative construction, piecewise and gradual, creations of our imperfect and incomplete grasp on physical reality. And there’s nothing wrong with that."

DAVID's comment: One simple solution is to accept God as the First Cause. String theory is obviously dead and no other is apparently on the way.

There is nothing simple about God as the First Cause. Even among believers, there is no consensus on his purposes or his nature. It is just as simple to say the First Cause is energy and matter. Or to accept that we haven’t a clue, and “there’s nothing wrong with that”. But it is an endlessly fascinating subject for discussion, as has been confirmed by our nine years of exchanges!

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dhw: There is nothing simple about God as the First Cause. Even among believers, there is no consensus on his purposes or his nature. It is just as simple to say the First Cause is energy and matter. Or to accept that we haven’t a clue, and “there’s nothing wrong with that”. But it is an endlessly fascinating subject for discussion, as has been confirmed by our nine years of exchanges!

Hear, Hear! Nine years and four plus boxes of archives!

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Quantum theory refers to very tiny places and general relativity (gravity) looks at large places. they are two theories that don't fit each other. Here is a new try:

http://nautil.us//issue/49/the-absurd/will-quantum-mechanics-swallow-relativity-rp?utm_...

"Hogan, champion of the quantum view, is what you might call a lamp-post physicist: Rather than groping about in the dark, he prefers to focus his efforts where the light is bright, because that’s where you are most likely to be able to see something interesting. That’s the guiding principle behind his current research. The clash between relativity and quantum mechanics happens when you try to analyze what gravity is doing over extremely short distances, he notes, so he has decided to get a really good look at what is happening right there. “I’m betting there’s an experiment we can do that might be able to see something about what’s going on, about that interface that we still don’t understand,” he says.

"A basic assumption in Einstein’s physics—an assumption going all the way back to Aristotle, really—is that space is continuous and infinitely divisible, so that any distance could be chopped up into even smaller distances. But Hogan questions whether that is really true. Just as a pixel is the smallest unit of an image on your screen and a photon is the smallest unit of light, he argues, so there might be an unbreakable smallest unit of distance: a quantum of space.

"In Hogan’s scenario, it would be meaningless to ask how gravity behaves at distances smaller than a single chunk of space. There would be no way for gravity to function at the smallest scales because no such scale would exist. Or put another way, general relativity would be forced to make peace with quantum physics, because the space in which physicists measure the effects of relativity would itself be divided into unbreakable quantum units. The theater of reality in which gravity acts would take place on a quantum stage.

***

"Chunky space does not neatly align with the ideas in string theory—or in any other proposed physics model, for that matter. “It’s a new idea. It’s not in the textbooks; it’s not a prediction of any standard theory,” Hogan says, sounding not the least bit concerned. “But there isn’t any standard theory right?”

"If he is right about the chunkiness of space, that would knock out a lot of the current formulations of string theory and inspire a fresh approach to reformulating general relativity in quantum terms. It would suggest new ways to understand the inherent nature of space and time. And weirdest of all, perhaps, it would bolster an au courant notion that our seemingly three-dimensional reality is composed of more basic, two-dimensional units. Hogan takes the “pixel” metaphor seriously: Just as a TV picture can create the impression of depth from a bunch of flat pixels, he suggests, so space itself might emerge from a collection of elements that act as if they inhabit only two dimensions.

***

"For the scale of chunkiness that Hogan hopes to find, he needs to measure distances to an accuracy of 10-18 meters, about 100 million times smaller than a hydrogen atom, and collect data at a rate of about 100 million readings per second. Amazingly, such an experiment is not only possible, but practical. “We were able to do it pretty cheaply because of advances in photonics, a lot of off the shelf parts, fast electronics, and things like that,” Hogan says. “It’s a pretty speculative experiment, so you wouldn’t have done it unless it was cheap.” The holometer is currently humming away, collecting data at the target accuracy; he expects to have preliminary readings by the end of the year.

***

"For most of today’s theorists, though, belief in the primacy of quantum mechanics runs deeper still. At a philosophical—epistemological—level, they regard the large-scale reality of classical physics as a kind of illusion, an approximation that emerges from the more “true” aspects of the quantum world operating at an extremely small scale. Chunky space certainly aligns with that worldview.

***

"Whether or not he finds his quantum structure of space, Hogan is confident the holometer will help physics address its big-small problem. It will show the right way (or rule out the wrong way) to understand the underlying quantum structure of space and how that affects the relativistic laws of gravity flowing through it."

Comment: Quantum mechanics must be at the basis of the universe. These new ideas are needed.

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A different type of detector just ungraded is rumored to have found the waves. It is the LIGO which detects a slight difference in time between two observant stations in Washington and Louisiana, as a wave passes:-https://en.wikipedia.org/wiki/LIGO-"LIGO operates two gravitational wave observatories in unison: the LIGO Livingston Observatory in Livingston, Louisiana, and the LIGO Hanford Observatory, on the DOE Hanford Site , located near Richland, Washington. These sites are separated by 3,002 kilometers (1,865 miles). Since gravitational waves are expected to travel at the speed of light, this distance corresponds to a difference in gravitational wave arrival times of up to ten milliseconds. Through the use of triangulation, the difference in arrival times can determine the source of the wave."-The rumors from two sources, among others:-https://www.washingtonpost.com/news/speaking-of-science/wp/2016/01/12/why-is-this-famous-physicist-tweeting-rumors-about-gravitational-waves/?wpmm=1&wpisrc=nl_evening-"The first thing you should know about this rumor is that it's from a pretty believable source: Lawrence Krauss is an award-winning physicist and a respected science communicator and advocate. Krauss actually started the rumor back in September, but confirmed it on Monday."-http://www.theguardian.com/science/2016/jan/12/gravitation-waves-signal-rumoured-science-"According to the rumours, scientists on the team are in the process of writing up a paper that describes a gravitational wave signal. If such a signal exists and is verified, it would confirm one of the most dramatic predictions of Albert Einstein's century-old theory of general relativity."-Comment: Wow, maybe!

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It appears there are several new detectors around the world:-http://blogs.scientificamerican.com/guest-blog/the-waves-no-one-can-find/?WT.mc_id=SA_WR_20160113-"One of the best hopes for achieving the necessary sensitivity is light. In a technique known as interferometry, a laser beam is split to send two light waves down perpendicular tunnels several kilometers in length. The waves reflect off mirrors to return to the same position and recombine. The intensity of the newly recombined beam depends on the alignment (or phase) of the peaks and troughs in the two waves. This makes it incredibly sensitive to how far each wave has traveled before it recombines.-"For gravitational wave detection, the tunnel lengths ensure that the peaks from one wave meet the troughs from the second wave. This is known as destructive interference and it cancels the light of the recombined wave entirely. But when a gravitational wave passes, it distorts the lengths of the tunnels, changing how far each wave travels. The peaks and troughs of the two light waves then no longer perfectly align; the beams no longer cancel each other, and a signal is produced.-***-"Buried 200 m below the Ikenoyama mountain in the Gifu prefecture of Japan, the Kamioka Gravitational Wave Detector (KAGRA) is about to turn on its lasers for the first time. Led by the 2015 Physics Nobel Laurette, Takaaki Kajita, KAGRA's sensitivity should allow it to detect gravitational waves up to 700 million light years away, ten times further than the previous generation of detectors. Its main target will be binary neutron stars; incredibly dense stellar corpses that emit energy in the form of gravitational waves as their orbits around each other decay. Its enormous range means it's not restricted to events only in our own galaxy, so KAGRA should detect multiple gravitational wave events per year.-"KAGRA's underground location minimizes seismic noise from the ever-rumbling Japan. The surrounding gneiss rock is famous for its hardness, causing the mountain to act as a single entity that is resistant to shakes. KAGRA's second new feature is cryogenic cooling, bringing the system down to an frosty -253° Celsius (20 K), to stifle any thermal vibrations."

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BICEPS2 looks for primordial waves from the Big Bang. LEGO looks for current waves from collisions between massive objects like black holes:-http://www.scientificamerican.com/article/not-all-gravitational-waves-are-created-equal/?WT.mc_id=SA_DD_20160114-"LIGO searches for powerful gravitational waves created by some of the most violent events in the cosmos, such as collisions between black holes or dense objects called neutron stars. They're looking for the most cataclysmic events you could imagine happening in our galaxy or nearby galaxies, says Lawrence Krauss, a physicist at Arizona State University in Tempe who is not involved in the experiment and tweeted about his excitement over the rumors. The mass is so great in such a small area that the gravitational fields are strong enough that most of the energy of the collision would be emitted in the form of gravitational waves.-"Gravitational waves are a prediction of Albert Einstein's general relativity, which explained that gravity results from a curvature in spacetime. Whenever mass moves through space it warps the geometry of the universe around it, causing other nearby traveling masses to move along curving paths.-***-"The gravitational waves LIGO is looking for are thought to arise every so often in the modern universe around us. BICEP2, on the other hand, targets primordial gravitational waves born in the very early universe. Based at the South Pole, BICEP2 studies the cosmic microwave background (CMB) light released just some 380,000 years after the big bang and looks not for the waves themselves but for a signature they might have left in the light. The telescope is searching for imprints in the CMB of gravitational waves that might have been created if the universe ballooned rapidly in size immediately after its birth, as predicted by a theory called inflation. According to inflation, tiny random quantum fluctuations in spacetime would have stretched along with the universe, producing gravitational waves that would have left polarizationthat is, a special orientation of the light wavesin the CMB.-***-"A discovery of either primordial or contemporary gravitational waves would be a major breakthrough, but for different reasons. The gravitational waves that BICEP2 was trying to detect would have been a signal from the very early universe, says Marc Kamionkowski, an astrophysicist at Johns Hopkins University who predicted in 1997 how primordial gravitational wave imprints could be found. The discovery would have offered proof for inflation theory and could have revealed details about how the first moments of cosmic history played out. LIGO's gravitational waves, if they are real, would probe how gravity works in extreme objects such as neutron stars and black holes, where current physics theories break down. And whereas BICEP2 seeks imprints on the CMB light created by gravitational waves, LIGO is aiming to directly detect the waves themselves, which would be a first.-Comment: Discovery of both types would confirm Einstein's space-time gravity theory and also inflation theory with solid evidence.

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A new proposal about quantum space and an 'ether' of virtual particles from Paul DAvies;-http://www.meta-religion.com/Physics/Cosmological_physics/liquid_space.htm-"In 1976 I began investigating what quantum mechanics might have to say. According to quantum field theory, the vacuum has some strange properties. Heisenberg's uncertainty principle implies that even in empty space, subatomic particles such as electrons and photons are constantly popping into being from nowhere, then fading away again almost immediately. This means that the quantum vacuum is a seething frolic of evanescent "virtual particles".-"Although these particles lack the permanence of normal matter, they can still have a physical influence. For example, a pair of mirrors arranged facing one another extremely close together will feel a tiny force of attraction, even in a perfect vacuum, because of the way the set-up affects the behaviour of the virtual photons. This has been confirmed in many experiments.-"So clearly the quantum vacuum resembles the ether, in the sense that there's more there than just nothing.-"Like the ether of old, the quantum vacuum exerts no frictional drag on a particle with constant velocity.-"But it's a different story with acceleration. The quantum vacuum does affect accelerating particles. For example, an electron circling an atom is jostled by virtual photons from the vacuum, leading to a slight but measurable shift in its energy.-***-"And there is a curious pointer to something deeper. Quantum physics is famed for its "non-locality": the fact that it is not possible to characterise the physical situation at a point in space without reference to the state of the system in the wider surroundings. The quantum vacuum is no exception, since its state is defined across all of space. This enables it to "feel" the structure of the entire Universe, and thereby to link the global and the local in precisely the manner that Mach had in mind. This nonlocality hints at a possible connection between local physics and distant matter in the Universe -a connection that could be mediated by the quantum ether. Among other things, it could explain why we share an absolute frame of acceleration with the distant stars.-"This is not the ether of Maxwell. Rather than being the medium that transmits light, it is made of light-virtual photons-and other virtual particles.-***-"The Greek philosophers' original argument against the void has lost much of its force, because physicists today have little difficulty imagining the concept of empty space. But now they question whether space itself is truly fundamental. Perhaps space as we know it is a special configuration of a deeper quantum entity, the properties of which we can only guess at. Far from abhorring a vacuum, nature may have worked very hard to create one.-Comment: Another example that our space is something, not a true vacuum but a virtual vacuum, and the entire universe is connected; it is truly non-local. A real mystery.

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An announcement about gravitational waves on Thursday. All the hype says they are found!:-http://blogs.scientificamerican.com/dark-star-diaries/why-you-should-be-excited-about-this-week-s-big-ligo-announcement/?WT.mc_id=SA_DD_20160210-"They've called not one press conference but three of them, at least. Simultaneous events are now scheduled for Thursday in Washington, D.C., London, and Paris, and it seems like more are being announced every hour. -***-"As you've probably heard, rumor is that LIGO has detected gravitational waves, possibly ones caused by the merger of two stellar-mass black holes. (The merger of two neutron stars or a particularly violent supernova could also send ripples through spacetime that LIGO could detect.) Kip Thorne, Caltech general-relativity guru and arguably LIGO's most prominent supporter, has explained many times over the years why a discovery like this would be exciting, but the line of his I like best comes from 300 Years of Gravitation (1987): If cosmic gravitational waves can be detected and studied, they will create a revolution of our view of the universe comparable to or greater than that which resulted from the discovery of radio waves.-***-"The opening of the radio sky, of course, led to the discovery of radio galaxies, quasars, and astrophysical black holes. The detection of gravitational waves could be similarly transformative because it would mark the beginning of an era in which scientists can use gravitational waves just as they use electromagnetic radiationas a means of observing the cosmos.-***-"Naturally, I'm particularly interested in what this could mean for the study of black holes. The next few years already look incredibly promising; as early as next spring, the Event Horizon Telescope should start looking for the shadow of the black hole at the center of the Milky Way, meaning we might soon see, with actual pictures, the faces of these things. Adding gravitational-wave detectors to the toolbox is like growing a new sense organ. We'll find out Thursday whether this organ has heard anything yet."-Comment: Fingers crossed. Wow!

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Yes, waves found:-http://www.nature.com/news/einstein-s-gravitational-waves-found-at-last-1.19361?WT.mc_id=EMI_NA_1602_NEWSGRAVWAVESFOUND_PORTFOLIO&spMailingID=50678145&spUserID=MTc2NjI2NDU0MwS2&spJobID=861382486&spReportId=ODYxMzgyNDg2S0-"One hundred years after Albert Einstein predicted the existence of gravitational waves, scientists have finally spotted these elusive ripples in space-time.-"In a highly anticipated announcement, physicists with the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) revealed on 11 February that their twin detectors have heard the gravitational 'ringing' produced by the collision of two black holes about 400 megaparsecs (1.3 billion light-years) from Earth.-***-"One black hole was about 36 times the mass of the Sun, and the other was about 29 solar masses. As they spiralled inexorably into one another, they merged into a single, more-massive gravitational sink in space-time that weighed 62 solar masses, the LIGO team estimates.-'These amazing observations are the confirmation of a lot of theoretical work, including Einstein's general theory of relativity, which predicts gravitational waves, says physicist Stephen Hawking of the University of Cambridge, UK. Hawking noted that Einstein himself never believed in black holes.-"This is the first black-hole merger that scientists have observed. The violent event temporarily radiated more energy  in the form of gravitational waves  than all the stars in the observable Universe emitted as light in the same amount of time."-Matt Strassler explains the significance:-http://profmattstrassler.com/2016/02/11/advance-thoughts-on-ligo/-" We are witnessing the birth of an entirely new field of science: gravitational-wave astronomy. This type of astronomy is complementary to the many other methods we have of looking at the universe. What's great about gravitational wave astronomy is that although dramatic events can occur in the universe without leaving a signal visible to the eye, and even without creating any electromagnetic waves at all, nothing violent can happen in the universe without making waves in space-time. Every object creates gravity, through the curvature of space-time, and every object feels gravity too. You can try to hide in the shadows, but there's no hiding from gravity.-***-" Experts were pretty certain that mergers of black holes of this size happen on a fairly regular basis  gravitational wave astronomy might soon show us something completely unanticipated. Perhaps it will teach us surprising facts about the numbers or properties of black holes, neutron stars, or other massive objects. Perhaps it will help us solve some existing mysteries, such as those of gamma-ray bursts. Or perhaps it will reveal currently unsuspected cataclysmic events that may have occurred somewhere in our universe's past."-Comment: Einstein's spacetime fully validated!

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More commentary on the discovery:-http://www.scientificamerican.com/article/not-all-gravitational-waves-are-created-equal/?WT.mc_id=SA_IDR_20160211-"Gravitational waves are a prediction of Albert Einstein's general relativity, which explained that gravity results from a curvature in spacetime. Whenever mass moves through space it warps the geometry of the universe around it, causing other nearby traveling masses to move along curving paths. Every time I move my arms my body is changing the curvature of space around me, which produces a ripple in spacetime, Krauss says. It's just that those gravitational waves are so small they are imperceptible. LIGO uses detectors in Louisiana and Washington State to search for tiny differences in the time it takes light to travel down perpendicular pathways. The pathways are the same length but if a gravitational wave passed by, it would stretch spacetime in one direction, causing only one of the two pathways to expand and thus inducing a minute difference in the travel time for the light. They have to measure a path difference smaller than one one-hundredth of a proton, Krauss says. It's amazing they can do that.-"The gravitational waves LIGO is looking for are thought to arise every so often in the modern universe around us. BICEP2, on the other hand, targets primordial gravitational waves born in the very early universe. Based at the South Pole, BICEP2 studies the cosmic microwave background (CMB) light released just some 380,000 years after the big bang and looks not for the waves themselves but for a signature they might have left in the light. The telescope is searching for imprints in the CMB of gravitational waves that might have been created if the universe ballooned rapidly in size immediately after its birth, as predicted by a theory called inflation. According to inflation, tiny random quantum fluctuations in spacetime would have stretched along with the universe, producing gravitational waves that would have left polarizationthat is, a special orientation of the light wavesin the CMB. In April 2015 the team announced, to much fanfare, that they had discovered this polarization. But later studies revealed that what they saw is most likely contamination from nearby dust in our galaxy.-***-"A discovery of either primordial or contemporary gravitational waves would be a major breakthrough, but for different reasons. The gravitational waves that BICEP2 was trying to detect would have been a signal from the very early universe, says Marc Kamionkowski, an astrophysicist at Johns Hopkins University who predicted in 1997 how primordial gravitational wave imprints could be found. The discovery would have offered proof for inflation theory and could have revealed details about how the first moments of cosmic history played out. LIGO's gravitational waves, if they are real, would probe how gravity works in extreme objects such as neutron stars and black holes, where current physics theories break down. And whereas BICEP2 seeks imprints on the CMB light created by gravitational waves, LIGO is aiming to directly detect the waves themselves, which would be a first.-Comment Again, wow!

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Strassler comments: - http://cms.web.cern.ch/sites/cms.web.cern.ch/files/styles/large/public/field/image/Imag... - "LIGO got a Christmas (US) present: Dec 25th/26th 2015, two more black holes were detected coalescing 1.4 billion light years away  changing the length of LIGO's arms by 300 parts in a trillion trillion, even less than the first merger observed in September. The black holes had 14 solar masses and 8 solar masses, and merged into a black hole with 21 solar masses, emitting 1 solar mass of energy in gravitational waves. In contrast to the September event, which was short and showed just a few orbits before the merger, in this event nearly 30 orbits over a full second are observed, making more information available to scientists about the black holes, the merger, and general relativity. (Apparently one of the incoming black holes was spinning with at least 20% of the maximum possible rotation rate for a black hole.) - "The signal is not so bright as the first one, so it cannot be seen by eye if you just look at the data; to find it, some clever mathematical techniques are needed. But the signal, after signal processing, is very clear. (Signal-to-noise ratio is 13; it was 24 for the September detection.) For such a clear signal to occur due to random noise is 5 standard deviations  officially a detection. The corresponding chirp is nowhere near so obvious, but there is a faint trace. - *** - "Let's remember also that advanced-LIGO is still not running at full capacity. When LIGO starts its next run, six months long starting in September, the improvements over last year's run will probably give a 50% to 100% increase in the rate for observed mergers. In the longer run, the possibility of one merger per week is possible. - "Meanwhile, VIRGO in Italy will come on line soon too, early in 2017. Japan and India are getting into the game too over the coming years. More detectors will allow scientists to know where on the sky the merger took place, which then can allow normal telescopes to look for flashes of light (or other forms of electromagnetic radiation) that might occur simultaneously with the merger as is expected for neutron star mergers but not widely expected for black hole mergers. The era of gravitational wave astronomy is underway." - Comment: Fantastic. Einstein right again.

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This theory has been around for some time. Steinhardt and Turok produced a paper on it in 2002. It's back:-https://www.newscientist.com/article/2096622-our-universe-could-be-reborn-as-a-bouncing-baby-cosmos/-"The universe could bounce through its own demise and emerge unscathed. A new big bounce model shows how the universe could shrink to a point and grow again, using just the cosmic ingredients we know about now.-***- 'Inflation is the champion until dethroned, says Robert Caldwell at Dartmouth College in Hanover, New Hampshire.-"But there have always been alternative models to compete with inflation. One major contender is the big bounce model, in which our universe rose from the ashes of an earlier cosmos that ended in a big crunch, a process set to repeat when the universe comes to an end. Those models have also struggled to explain the singularity, though.-'The bouncing models until this point had to add extra ingredients or assumptions in order to make sense of how the universe got through or avoided the singularity, says Neil Turok of the Perimeter Institute in Waterloo, Canada.-"In a new paper, Turok and Steffen Gielen at Imperial College London take a different approach. The spirit of our work is to focus on simplicity, Turok says. We're not adding bells and whistles to the physics we already know.-"The pair focused on a principle from particle physics: the idea that, at very high energies, matter behaves like light. In particular, it becomes scale-invariant - the equations that describe its behaviour are the same no matter the energy of the light, or the size of universe that contains it. (my bold)-'The universe can shrink to zero and reappear, and the light is none the wiser, Turok says. That's roughly speaking what happens.-"Turok and Gielen applied that principle to a universe that is completely smooth and the same in all directions - not exactly realistic, but that allowed them to write down the equations governing this universe and solve them exactly.-"The solution predicts a cosmos that bounces through the singularity in a process similar to quantum tunnelling, which allows electrons to pass through walls or other barriers.-'It's completely unambiguous: it goes through the crunch and out in a bang, Turok says.-'This is potentially pretty exciting, Caldwell says. They have figured out a way to evolve through a bounce without introducing any funny matter. I think it's an important step to developing a theory of the early universe that doesn't resort to inflation.-"The idea is interesting, says Martin Bojowald of Pennsylvania State University. But while those simplifying assumptions might have made it easier to write down a complete equation, they might make it harder to prove that it describes the real universe."-Comment: The bouncing universe is an idea that has been around for awhile. That it gets back to using light (see the bolded section)ties in with the long series of recent submissions on information which refers to the use of light, quoting the OT, in the origin of the universe and Earth. So far it is still singularity and Big Bang.

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This article explains how the gravitational wave studies will enlarge our knowledge of the universe: - https://aeon.co/ideas/gravitational-waves-will-bring-the-extreme-universe-into-view?utm... - "The first direct detection of gravitational waves on 14 September 2015 proved that massive objects can ripple the structure of space, verifying a key prediction of Albert Einstein's general theory of relativity. The second detection, made on 26 December 2015 and announced this June, firmly established gravitational waves as a new window to the Universe. But even more exciting are the detections yet to come: the thousands of signals that should soon be observed by the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo experiments. They will transform our understanding of black holes, neutron stars, supernova explosions, and perhaps even the origin and fate of the cosmos itself. - *** - "Drawing on data from those two events, my colleagues in the LIGO and Virgo collaborations have tested general relativity in novel ways, far outside our terrestrial experience. And we have shown that black holes collide more often than expected, which has lead some researchers to speculate that black holes might be abundant enough to qualify as a variety of dark matter. - *** - "We also expect to observe mergers of neutron stars, the ultradense remains of stars that were too small to form black holes. Whereas black holes are so extreme that they are breathtakingly simple (completely described by their mass, spin and charge), neutron stars show the Universe at its most bizarre and complex. They contain more mass than our Sun packed into a sphere the size of Manhattan, with magnetic fields that can be more than a billion times as powerful as Earth's. We do not understand how matter this dense behaves, nor do we know how their magnetic fields are sustained. - "Unlike black holes, naked neutron stars emit light and other forms of radiation. Neutron-star mergers can produce a rapid flash of gamma rays or X-rays, along with a faint optical afterglow that can linger for days or weeks. With LIGO and Virgo operating in concert, we can localise the position of colliding neutron stars to within a few degrees in the sky. Optical telescopes can then search this patch of sky for a fading signal emitted by radioactive material ejected during the merger. - *** - "Gravitational waves can also show what happens in a core-collapse' supernova explosion, which occurs when the core of a massive star exhausts its nuclear fuel and is crushed under the star's immense mass. This is an open question in astrophysics, because the mechanism that drives the explosion is hidden deep inside the star. Gravitational waves from supernovae will travel directly from the star's centre to our detectors. - *** - "Looking out on an even grander scale, gravitational waves from neutron star mergers will give us a fresh way to study the expansion of the Universe. Our current picture of cosmology - in which the Universe is expanding following the Big Bang, and is accelerating due to an unseen dark energy' - relies heavily on observations of supernovae in distant galaxies. Gravitational waves will provide complementary information: the intensity (amplitude) of the gravitational signal tells us the distance to the event, while the optical appearance of the merger reveals how much its light has been stretched, or redshifted, on its way to Earth. These two pieces of information define the rate at which the Universe is expanding. - *** - "Finally, LIGO and Virgo might detect a faint background hum of gravitational waves that pervades the entire Universe, constantly vibrating all of empty space. Many theories predict an omnipresent gravitational energy produced either from the accumulation of astrophysical events such as black hole mergers or from an early, extremely rapid episode of cosmic inflation immediately after the Big Bang. If the hum is loud enough, it will show up as a correlated signal between widely separated detectors such as LIGO and Virgo. Measuring the gravitational-wave background would be a dramatic achievement. - *** - "LIGO and Virgo have already performed a staggering feat. Consider the properties of the September 14 event: the signal was generated by two objects, each roughly 35 times the mass of our Sun, locked in a decaying orbit the size of Switzerland, circling each other 50 times a second. The energy involved was staggering, briefly exceeding that of all the starlight in the Universe, but the signal that reached Earth was among the most imperceptible things that humans have ever measured. As gravitational-wave detections make the transition from sensational discoveries to routine tools for astrophysics and cosmology, the invisible shaking of space will, paradoxically, illuminate parts of the Universe that were entirely dark until now. - Comment: We really know so little. These experimental methods are very expensive but hopefully they will be supported as they ae refined. So much to learn.

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From two colliding black holes:

https://cosmosmagazine.com/space/black-hole-collision-reveals-clues-to-early-cosmos

"Scientists have observed one of the most powerful astronomical events ever seen — the collision of two giant black holes to form an even larger black hole.

"It’s the third time since 2015 that such a collision has been observed via an instrument called LIGO (Laser Interferometer Gravitational-wave Observatory), which consists of a pair of detectors, one in Hanford, Washington, USA, and the other in Livingston, Louisiana, each designed to measure gravitational waves from distant cosmological events.

"Gravitational waves are ripples in the fabric of space, created by movements of massive objects.

“Normally we don’t think of space as having any properties at all, so it’s counterintuitive,” says Michael Landry, director of LIGO’s Hanford observatory. Nevertheless, he says, Einstein’s theory of general relativity predicts that space can expand, contract, or vibrate, thereby distorting the medium in which we all live.

"Such waves can be measured, he adds, because the distortions they produce look like changes in the length of any object they pass through. Landry compares it to stretching the canvas of a painting. “If I stretch the medium, the painting gets distorted,” he says.

"In this case, what LIGO saw were the rapidly vibrating distortions produced as the two black holes spiraled toward each other before merging, releasing as much energy in the form of gravitational waves as would be produced if two stars the size of the Sun were converted from mass into energy in about one-third of a second. Once the collision was complete, the new black hole had a mass about 50 times that of the Sun.

***

" Careful computer modeling, she adds, shows that the signals detected by LIGO contain the “gravitational fingerprints” of black holes whose spins did not align with their orbit.

“'This favors the theory that these two black holes formed separately then paired up, rather than being formed from the collapse of two already paired stars,” she says."

Comment: Einstein is again confirmed. Space-time is a fabric that can ripple.

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There is now a third detector for gravitational waves, which means they can triangulate and know the area where it came from as black holes collide:

https://profmattstrassler.com/2017/09/27/ligo-and-virgo-announce-a-joint-observation-of...

"Welcome, VIRGO! Another merger of two big black holes has been detected, this time by both LIGO’s two detectors and by VIRGO as well.

"Aside from the fact that this means that the VIRGO instrument actually works, which is great news, why is this a big deal? By adding a third gravitational wave detector, built by the VIRGO collaboration, to LIGO’s Washington and Louisiana detectors, the scientists involved in the search for gravitational waves now can determine fairly accurately the direction from which a detected gravitational wave signal is coming. And this allows them to do something new: to tell their astronomer colleagues roughly where to look in the sky, using ordinary telescopes, for some form of electromagnetic waves (perhaps visible light, gamma rays, or radio waves) that might have been produced by whatever created the gravitational waves.

"The point is that with three detectors, one can triangulate. The gravitational waves travel for billions of years, traveling at the speed of light, and when they pass by, they are detected at both LIGO detectors and at VIRGO. But because it takes light a few thousandths of a second to travel the diameter of the Earth, the waves arrive at slightly different times at the LIGO Washington site, the LIGO Louisiana site, and the VIRGO site in Italy. The precise timing tells the scientists what direction the waves were traveling in, and therefore roughly where they came from. In a similar way, using the fact that sound travels at a known speed, the times that a gunshot is heard at multiple locations can be used by police to determine where the shot was fired.

"You can see the impact in the picture below, which is an image of the sky drawn as a sphere, as if seen from outside the sky looking in. In previous detections of black hole mergers by LIGO’s two detectors, the scientists could only determine a large swath of sky where the observed merger might have occurred; those are the four colored regions that stretch far across the sky. But notice the green splotch at lower left. That’s the region of sky where the black hole merger announced today occurred. The fact that this region is many times smaller than the other four reflects what including VIRGO makes possible. It’s a small enough region that one can search using an appropriate telescope for something that is making visible light, or gamma rays, or radio waves.

"While a black hole merger isn’t expected to be observable by other telescopes, and indeed nothing was observed by other telescopes this time, other events that LIGO might detect, such as a merger of two neutron stars, may create an observable effect. We can hope for such exciting news over the next year or two."

Comment: Another advance using Einstein's theories. Be sure to look at the illustration.

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The reasons are explained:

https://cosmosmagazine.com/space/slowing-down-the-stars

"Astronomers studying a spiral galaxy in the constellation Fornax have found a clue not only to why stars are still forming today, but why ones the age of our sun even exist at all.
Under the standard Big Bang theory of the universe’s origins, everything began 13.8 billion years ago, when a titanic explosion flung matter and energy out in all directions. As the universe expanded, a lot of other things occurred in its early years, including the formation of galaxies, giant gas clouds, and stars. In the process, most of the star-forming material in galaxies should have condensed into stars long ago, when the universe was only a fraction of its present age.

"But that is simply not the case. More than half of the galaxies we see, including our own, are actively forming stars, right now. And some, known as starburst galaxies are doing so very actively. Furthermore, our own sun is only about 4.6 billion years old — or one-third the age of the universe. (my bold)

"That makes it young, given the fact that the star birth rate probably peaked before the universe was much more than a billion years old, says Fatemeh Tabatabaei.

"Clearly, something must have slowed the rate of star formation — a process known as star-formation quenching — preserving star-forming matter for future generations of stars.

"In order to study this process, a team of astronomers led by Tabatabaei turned their attention to NCG 1079, a galaxy that at a distance of 45 million light years is bright enough to have been discovered in 1790 by British astronomer William Herschel, who only a few years earlier had found the planet Neptune.

***

It is known that quenched galaxies mostly have a super-massive black hole, and that quenching starts first at their centres,” she says. “NCG 1097 provides an ideal laboratory because it could help us catch [it] in the act of quenching.”

***

"What they found was that large magnetic fields, probably enhanced by the central black hole, affect the gas clouds that would normally collapse into stars, thereby inhibiting their collapse. These forces can even break big clouds into smaller ones, she says, ultimately leading to the formation of smaller stars.

"All told, she adds, the finding is important because it helps explain cosmic evolution and the way galaxies evolve.

"Not to mention that if all our own galaxy’s star-forming matter had been gobbled up 12 to 13 billion years ago, we humans would not be here today, circling a much younger star, wondering why we exist. "

Comment: Although our galaxy is like many others it has a special arrangement to allow our sun to appear later than many.

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QUOTE: "Experts were pretty certain that mergers of black holes of this size happen on a fairly regular basis  gravitational wave astronomy might soon show us something completely unanticipated. Perhaps it will teach us surprising facts about the numbers or properties of black holes, neutron stars, or other massive objects. Perhaps it will help us solve some existing mysteries, such as those of gamma-ray bursts. Or perhaps it will reveal currently unsuspected cataclysmic events that may have occurred somewhere in our universe's past."-David's comment: Einstein's spacetime fully validated!-No mention of your theory that all of these events were part of God's plan to create humans! Once all the excitement has died down, I suspect we shall find that we have actually learned very little (so far). This breakthrough has served to confirm what scientists already believed. The remainder of the quote is a series of perhaps. Since the universe is full of unknowns, I have no doubt that increasingly sophisticated instruments will reveal more and more properties, numbers and cataclysms. Three cheers for technology, but perhaps we should wait for some sensational new discoveries about the origin, history and composition of the universe before we go dancing in Stockholm.

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David's comment: Einstein's spacetime fully validated!
> 
> dhw: No mention of your theory that all of these events were part of God's plan to create humans! Once all the excitement has died down, I suspect we shall find that we have actually learned very little (so far). This breakthrough has served to confirm what scientists already believed.-for such an imaginative person, you certainly missed the point. This is humans uncovering the mysteries of the universe with their vastly superior intellect and their never unending drive to explain everything.

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David's comment: Einstein's spacetime fully validated!-dhw: No mention of your theory that all of these events were part of God's plan to create humans! Once all the excitement has died down, I suspect we shall find that we have actually learned very little (so far). This breakthrough has served to confirm what scientists already believed.-DAVID: for such an imaginative person, you certainly missed the point. This is humans uncovering the mysteries of the universe with their vastly superior intellect and their never unending drive to explain everything.-I share your admiration for our never ending human quest for truth, but why have you made a general point about humans when my comment was specifically about this particular event? It has NOT uncovered the mysteries of the universe. It appears to have confirmed that two black holes collided a billion or so years ago. The rest is a series of perhaps. Practically every month there is some headline-grabbing breakthrough in the science world, and we are still left darkling. You omitted the main point of my post: Three cheers for technology, but perhaps we should wait for some sensational new discoveries about the origin, history and composition of the universe before we go dancing in Stockholm.

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> DAVID: for such an imaginative person, you certainly missed the point. This is humans uncovering the mysteries of the universe with their vastly superior intellect and their never unending drive to explain everything.
> 
> dhw: I share your admiration for our never ending human quest for truth, but why have you made a general point about humans when my comment was specifically about this particular event? -Because you specifically referred to my belief that God guided evolution to create humans.

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Will we ever understand why there is anything. This essay suggests we are following lots of dead ends:-https://aeon.co/essays/will-we-ever-understand-the-beginning-of-the-universe-"The science of cosmology has achieved wonders in recent centuries. It has enlarged the world we can see and think about by ontological orders of magnitude. Cosmology wrenched the Earth from the centre of the Universe, and heaved it, like a discus, into its whirling orbit around one unremarkable star among the billions that speed around the black-hole centre of our galaxy, a galaxy that floats in deep space with billions of others, all of them colliding and combining, before they fly apart from each other for all eternity. Art, literature, religion and philosophy ignore cosmology at their peril.-"But cosmology's hot streak has stalled. Cosmologists have looked deep into time, almost all the way back to the Big Bang itself, but they don't know what came before it. They don't know whether the Big Bang was the beginning, or merely one of many beginnings. Something entirely unimaginable might have preceded it. Cosmologists don't know if the world we see around us is spatially infinite, or if there are other kinds of worlds beyond our horizon, or in other dimensions. And then the big mystery, the one that keeps the priests and the physicists up at night: no cosmologist has a clue why there is something rather than nothing.-***-"Steinhardt looks out on his field, and sees a generation of theorists tinkering with models, wasting whole careers fiddling at the edges of a 30-year-old idea. I know why they're doing it,' he says. It's easy to do. You can make hundreds of these models, and you can tweak them so they fit the data. But usually, those fixes aren't the answer. Usually, you have to do something new.'-"Steinhardt is trying to do something new. He spends most of his research time working on an alternative cosmological theory. He thinks the Big Bang might have been a reaction to a contraction, a bounce, perhaps one in a sequence of bounces that extends deep into the past and maybe into eternity. He is trying to figure out whether a bounce could have yielded a smoothed, stretched, uniform cosmos such as ours. Sometimes he feels isolated, but he knows how to chip away. His sense of possibility powers him through. He told me he thinks we might be edging up to a transformative idea. Something that could rearrange reality as we know it. Something of Copernican magnitude.-"We should be excited that inflation is in trouble,' he said. That usually means we're on the brink of discovery. It means we're missing some idea, a really important idea. Something that's going to take over when it hits. Don't people want to be there for that?'"-Comment: Steinhardt is dismissing the string theorists. He is looking for a Big Bounce theory. This long essay is rich in description of the current battles of ideas. I've shown the beginning and the end, sort of.

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DAVID: Will we ever understand why there is anything. This essay suggests we are following lots of dead ends:
https://aeon.co/essays/will-we-ever-understand-the-beginning-of-the-universe
Comment: Steinhardt is dismissing the string theorists. He is looking for a Big Bounce theory. This long essay is rich in description of the current battles of ideas. I've shown the beginning and the end, sort of.-Thank you for this important essay, which generally confirms the point I keep making, which is that for all the sensational new discoveries trumpeted every month or so, we are no nearer to solving any of the mysteries of the universe. I have picked out a couple more quotes:-QUOTE: This whole BICEP2 thing has made some people more aware of it. It's been nice to have that aired out. But most people give us too much respect. They think we know what we're doing. They take too seriously these voices that say inflation is established theory.'-A boost for us sceptics!-QUOTE: When fine-tuning is used as evidence for a grand metaphysical apparatus capable of making anything and everything, it usually means that something has gone amiss.-This is part of an argument against God, further developed below:-QUOTE: There are other reasons one might be suspicious of the multiverse. This idea that the very existence of observers tells us something deep about the cosmos bears a disturbing resemblance to ancient anthropomorphic thinking. Once again, we find ourselves making grand, cosmic extrapolations from our own existence. Once again, the world is made in our image. The British philosopher Bertrand Russell had a great line on this sort of thinking: All such philosophies spring from self-importance, and are best corrected by a little astronomy.'-It seems to me that when a scientist admits that scientists are given too much respect, with the implication that they don't in fact know what they're doing, perhaps it is a little premature for him to assume that there is no grand metaphysical apparatus responsible for fine tuning. On the other hand, Bertrand Russell's line is a wonderful summing-up of my point about the immensity of the universe as a major obstacle to belief in a universal mind controlling it all - let alone manipulating it for the sake of us humans.

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> QUOTE: There are other reasons one might be suspicious of the multiverse. This idea that the very existence of observers tells us something deep about the cosmos bears a disturbing resemblance to ancient anthropomorphic thinking. - > 
> dhw: It seems to me that when a scientist admits that scientists are given too much respect, with the implication that they don't in fact know what they're doing, perhaps it is a little premature for him to assume that there is no grand metaphysical apparatus responsible for fine tuning. - A good reason for philosophers of science making their points. Multiverse theory tries to do away with God, and is not just grandiose theory. LIGO shows how well science can work. It is the weird philosophic thinking of scientists which muddies up the picture. Metaphysical apparatus can well be the reason for everything as the picket fence thinking states!

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dhw: It seems to me that when a scientist admits that scientists are given too much respect, with the implication that they don't in fact know what they're doing, perhaps it is a little premature for him to assume that there is no grand metaphysical apparatus responsible for fine tuning. - DAVID: A good reason for philosophers of science making their points. Multiverse theory tries to do away with God, and is not just grandiose theory. LIGO shows how well science can work. It is the weird philosophic thinking of scientists which muddies up the picture. Metaphysical apparatus can well be the reason for everything as the picket fence thinking states! - I presume by weird philosophic thinking of scientists you only mean those who do not share your theistic ideas. To restore the balance, let me repeat the part of my post you left out: - On the other hand, Bertrand Russell's line [concerning anthropocentric theism]: All such philosophies spring from self-importance, and are best corrected by a little astronomy] is a wonderful summing-up of my point about the immensity of the universe as a major obstacle to belief in a universal mind controlling it all - let alone manipulating it for the sake of us humans.


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I presume by weird philosophic thinking of scientists you only mean those who do not share your theistic ideas. To restore the balance, let me repeat the part of my post you left out:
> 
> On the other hand, Bertrand Russell's line [concerning anthropocentric theism]: All such philosophies spring from self-importance, and are best corrected by a little astronomy] is a wonderful summing-up of my point about the immensity of the universe as a major obstacle to belief in a universal mind controlling it all - let alone manipulating it for the sake of us humans.
> - Russell is simply saying the universe which God created in too immense for Him to handle. Circular rubbish.

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dhw: I presume by weird philosophic thinking of scientists you only mean those who do not share your theistic ideas. To restore the balance, let me repeat the part of my post you left out:
On the other hand, Bertrand Russell's line [concerning anthropocentric theism]: All such philosophies spring from self-importance, and are best corrected by a little astronomy] is a wonderful summing-up of my point about the immensity of the universe as a major obstacle to belief in a universal mind controlling it all - let alone manipulating it for the sake of us humans. - DAVID: Russell is simply saying the universe which God created in too immense for Him to handle. Circular rubbish. - David Turell is simply saying that God created the universe for the purpose of producing humans, and therefore the billions of solar systems, exploding supernovae, colliding black holes must be part of God's purpose of producing humans (though he doesn't know how). Everybody is running around in circles.

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> DAVID: Russell is simply saying the universe which God created in too immense for Him to handle. Circular rubbish.
> 
> dhw: David Turell is simply saying that God created the universe for the purpose of producing humans, and therefore the billions of solar systems, exploding supernovae, colliding black holes must be part of God's purpose of producing humans (though he doesn't know how). Everybody is running around in circles. - The only way to get life-giving elements is to create them in solar explosions, thanks to Fred Hoyle explaining it. God obviously evolved the universe and, of course, us.

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Theoretical physics is at a crossroads according to Alan Lightman, a crisis of faith that they can solve all the issues as to why we are here. It looks like they can't:-http://harpers.org/archive/2011/12/the-accidental-universe/?single=1-"Alan Guth, a pioneer in cosmological thought, says that the multiple-universe idea severely limits our hopes to understand the world from fundamental principles. And the philosophical ethos of science is torn from its roots. As put to me recently by Nobel Prize-winning physicist Steven Weinberg, a man as careful in his words as in his mathematical calculations, We now find ourselves at a historic fork in the road we travel to understand the laws of nature. If the multiverse idea is correct, the style of fundamental physics will be radically changed.-"The scientists most distressed by Weinberg's fork in the road are theoretical physicists. Theoretical physics is the deepest and purest branch of science. It is the outpost of science closest to philosophy, and religion. Experimental scientists occupy themselves with observing and measuring the cosmos, finding out what stuff exists, no matter how strange that stuff may be. Theoretical physicists, on the other hand, are not satisfied with observing the universe. They want to know why.-***-"According to the current thinking of many physicists, we are living in one of a vast number of universes. We are living in an accidental universe. We are living in a universe uncalculable by science.-***-" The recognition of this finetuning led British physicist Brandon Carter to articulate what he called the anthropic principle, which states that the universe must have the parameters it does because we are here to observe it. Actually, the word anthropic, from the Greek for man, is a misnomer: if these fundamental parameters were much different from what they are, it is not only human beings who would not exist. No life of any kind would exist.
If such conclusions are correct, the great question, of course, is why these fundamental parameters happen to lie within the range needed for life. Does the universe care about life? Intelligent design is one answer. Indeed, a fair number of theologians, philosophers, and even some scientists have used fine-tuning and the anthropic principle as evidence of the existence of God.-"Intelligent design, however, is an answer to fine-tuning that does not appeal to most scientists. The multiverse offers another explanation......We live in one of the universes that permits life because otherwise we wouldn't be here to ask the question.-***-"Physicists have named the energy associated with this cosmological force dark energy. No one knows what it is. Not only invisible, dark energy apparently hides out in empty space. Yet, based on our observations of the accelerating rate of expansion, dark energy constitutes a whopping three quarters of the total energy of the universe. It is the invisible elephant in the room of science.-***-"Thus, the original, rapidly expanding universe [inflation theory] spawns a multitude of new universes, in a never-ending process.-"String theory, too, predicts the possibility of the multiverse. -***- "Eternal inflation or string theory, or both, could turn out to be wrong. However, some of the world's leading physicists have devoted their careers to the study of these two theories.-***-"Theologians are accustomed to taking some beliefs on faith. Scientists are not. All we can do is hope that the same theories that predict the multiverse also produce many other predictions that we can test here in our own universe. But the other universes themselves will almost certainly remain a conjecture."-Comment: Fabulous summary essay. How about some faith? Read it all.

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An excellent essay by Neil Turok: - http://www.math.columbia.edu/~woit/wordpress/?p=8361 - "Turok discusses his point of view on whether we're at the end of physics, and I'm very much in agreement with what he has to say: - "I think what people are sort of expressing is that we haven't had a big revolution in physics. String theory was hoped for to be that revolution in the 1980s but it hasn't really panned out in the sense that it hasn't given a single prediction. Instead it's given us a huge collection of theories where, if you like, there's no overarching theory to tell which particular version of string theory is the one that describes the world. It's almost self-destructed, I would say because it turned out to be not just one theory but this vast collection of theories which could all give different descriptions of the world. - *** - "So I think that sort of theoretical catastrophe, as I view it  meaning the logical pursuit of quantum mechanics and relativity over a hundred years was tremendously successful at some level but finding its own successor theory, it hasn't been successful. - *** - "It looks like the founding principles of modern physics  quantum theory and relativity  have played out and they have not given us the answers we need. And so we have to go back and question those founding principles and find whatever it is, whatever new principle will replace them. - *** - "..and so some people talk about the multiverse where the universe would be wild and chaotic on large scales and almost anything you could imagine would actually exist somewhere in the universe. I mean, this is literally a scenario which became very popular among a category of physicists, that there is a multiverse out there. Yet the evidence is exactly the opposite. That, as we look around us, things could not be simpler. There's no evidence for chaos on large scales in the universe. It's totally the opposite. It's pristine, elegance, minimalism is all we see. So, I think this is a very, very exciting time to be doing theory. The challenge is enormous. The clues are enormous. We're waiting and we're preparing and we're encouraging people to take radical leaps." - Comment: Note he talks about simplicity, not complexity.

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this article covers the theory of solar system formation. Ours turns out to have a special ingredient:-http://phys.org/news/2016-04-earthsthe-chemistry-star-planet-formation.html-"A "solar system" like planetary system has at least one Earth-like planet at approximately 1 astronomical unit (AU) from the star - where more ideal conditions for life can develop - and at least one ice giant like Jupiter at 3-5 AU in order to keep away comets from the Earth-like planet. In our galaxy alone, there are around 10 billion stars and at least 10 million planets. For those stars similar to our sun, there exist over 4 million planetary systems similar to our solar system, with the closest Earth-like planet at 20 light years away.-***-"How does an Earth and a Jupiter form at their ideal distances from a star? Let's take a closer look at how stars and planets are created - via the astrochemical cycle. Essentially, dense clouds of gas and dust become so opaque and cold that they collapse into a disk. The disk, rotating around a to-be star, begins to transport mass in toward the center and angular momentum outward. Then, approximately 1% of the star mass is left over from the process, which is enough to form planets. This is also why planets around stars are ubiquitous.-"How are the planets formed? The dust grains unused by the star collide and grow, forming larger particles at specific distances from the star - called snowlines - where water vapor turns into ice and solidifies. These "dust bunnies" grow into planetesimals (~10-50 km diameter), such as asteroids and comets. If the force of gravity is large enough, the planetesimals increase further in size to form oligarchs (~0.1-10 times the mass of the Earth), that then become the large planets of the solar system.-"In our solar system, a process called dynamic reorganization occurred that restructured the order of our planets, putting Uranus before Neptune. This means that if other solar systems did not undergo such dynamic reorganization at an early point in formation of solar system, then other Earths may have lower organic and water content than our Earth. In that case, what constraints do we need to apply to determine if a water/organic delivery mechanism exists for exo-Earths? Although we do not currently have the scientific knowledge to answer this, with ALMA and the next generation of optical/IR telescopes, we will be able image the birth of solar systems directly and better understand how our universe came to be.-Comment: In bold is the theory of how planets switched positions, which helped Earth become so safe:-http://www.swri.org/4org/d15/planetsci/moon.htm-"In this model, the giant planets  Jupiter, Saturn, Uranus and Neptune  formed in a much more compact configuration than they have today. Just outside their orbits loomed a massive disk of comets. Gravitational interactions between the planets and the comet disk caused the planets to slowly migrate in space. Computer simulations indicate that, after hundreds of millions of years, Jupiter and Saturn reached orbits where their mutual gravitational kicks became quite pronounced. This triggered an instability that led to a violent reorganization of the outer solar system. Uranus and Neptune were pushed into the comet disk, scattering its members throughout the solar system. Some of these scattered objects then struck, or "bombarded," the planets and moons of the inner solar system."-Further comment: We still look very special.

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This is at the nub of string theory persisting despite no evidence and the quest for supersymmetry lasting for more than 40years with no smidgen of any proof:-http://www.pbs.org/wgbh/nova/next/physics/beauty-in-physics/-"Physicists often describe their earliest experiences with the field as borderline spiritual, moments in which they realized that theythey!can represent the world with math. They can describe how stars shrink to black holes, how hard you will hit your head if you slip on a banana peel, and how protons fall apart inside particle accelerators. That ability gives them a sense of control in the way that describing something gives humans dominion over it.-"For many physicists, this fosters a desire to get to the very, very bottom of things: the theory of everything. Such a theory, many physicists often believe, should be beautiful, simple, elegant, aesthetically pleasing. All of the forces should fit under one umbrella; all particles need to emerge from a nested set of equations. No ifs, ands, buts, or loopholes.-***-"The current gold standard for describing the nature of reality, the Standard Model, isn't physicists' ideal because, among other blemishes, it isn't perfectly symmetric, and the way it glues fundamental forces together is a little kludgy. That's partially why scientists have developed a new idea, called supersymmetry, which smooths and extends the Standard Model, giving each of those old-school particles a new-school supersymmetric counterpart.-"Despite the fact that particle physicists have found no evidence of supersymmetry, they continue hunting for the elusive supersymmetric partnerspartly because the theory is more aesthetically appealing than the Standard Model.-"But not all physicists believe that beauty should count as indirect evidence in favor of an idea.-***-"Marcelo Gleiser, a professor of physics at Dartmouth College, began his career searching for the underlying explanations of why the universe is the way it is. But about a decade ago, he felt uncertainty tugging at him. You look outside, and what you see in nature is not really perfection and symmetry, he says. You see patterns and formats which are not exactly perfect. Animal, tree, cloud, face: They obviously have symmetry but not perfect symmetry. It's not really perfection, but near perfection.-***-"He saw the blemishes in physics, too. There is more matter than antimatter, for example. If the two were perfectly balanced and symmetric, they would have annihilated each other and the universe would be emptythere'd be no physicists to wonder why, or to high-five each other after the discovery of a beautiful but deadly cosmic balance. Something happened during the history of the early universe to cause this, he says. That got me thinking that perhaps the insistence that we have in search of perfect symmetry is not a physics idea, but a bias.-***-"But some physicists may be reluctant to give up their beautiful theories, even if the data dictates they should. For example, while the Large Hadron Collider has so far failed to show evidence of supersymmetry, many have essentially said that the collision wasn't powerful enough or that some small modifications are all that's needed to fit the theory they love with the data they gathered.-'Supersymmetry has been around since 1974, for 42 years, and it doesn't really have any evidence that it's there. But people really bet their careers on this, Gleiser explains. Many physicists have spent 40 years working on this, which is basically their whole professional life.-"That may change in in ten years or so, he says, when further advances to the LHC could force the hangers-on to let go if the data they need doesn't materialize. If we don't find evidence, people who still stick to it after that are doing it as a philosophical practice, he says.-"Of course, it's certainly possible that the answers to life, the universe, and everything will be elegant. To physicists like Demers and Gleiser, that's not the problem: The problem is the a priori assumption that it is so. And if the foundational principles of the universe turn out to be ugly or tedious, perhaps we can find the beauty beneath the mess."-Comment: we have presented existing scientists who claim beauty alone is enough. that is religion! If it can't be measured it doesn't exist.

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It is only a theory with no proof. It does fit the facts as we know them, but that dos not mean it is correct: - https://aeon.co/ideas/cosmologists-should-be-more-skeptical-of-dark-matter?utm_source=A... - "To get computer models to look similar to the Universe around us, cosmologists have assumed that around 96 per cent of matter and energy are in forms that we cannot directly detect. You might think that this would make cosmologists wary of relying on such hypothetical substances. Yet for the majority working today, dark matter and dark energy are every bit as real as the stars and galaxies that we can see. - "Such corporate belief might work for business, but it has no place in science. - *** - "In the case of dark matter, the unquestioning belief is puzzling because the direct searches for these particles are coming up effectively empty?handed. Yet observations are routinely interpreted as being the result of dark matter. No other avenues of approach are taken by the vast majority of researchers. - "In reality, there are other possible solutions that at least warrant examination and comparison. In certain circumstances they fit the observations better than dark matter can. They usually involve a different approach, which is to alter how the force of gravity works or to relax an assumption about the way we think the Universe works, rather than add new constituents to the Universe. - "An alternative to dark matter was offered in 1981, by the physicist Mordehai Milgrom of the Weizmann Institute of Science in Israel. He postulated that gravity pulls a little more strongly than Newton's laws predict at extremely weak levels.
 
"A different approach to dark energy, which is thought to power an acceleration of the Universe, is to dismiss the assumption that matter is distributed evenly throughout space. Then the Universe will naturally change the rate at which it expands. - "Yet these ideas are generally sidelined in favour of the status quo. Why? - "Cosmology has become too conservative, too unwilling to step outside of the mainstream in the search for answers. While some might see this piece as an attack, it is simply the adoption of a position that I believe is truly scientific. One in which skepticism rules, and prevailing ideas are questioned. - "The true gold standard for science is constant self-questioning, constant re?evaluation, and constant open-mindedness in the search for better explanations. Theories are never true', even if they fit all known facts. They are merely hypotheses that have been shown to be useful. And they could fall at any moment if new observations come to light that do not fit. - "The sobering fact is that either 96 per cent of the Universe is unknown to us or we are completely wrong about the way we think the Universe works. Either way, cosmology is far from finished: we have a lot to work out." - Comment: this also applies to string theory, around forever and no proof. Current cosmological physicists are too closed minded. And the insistence on a multiverse is of the same ilk.

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QUOTE: "The sobering fact is that either 96 per cent of the Universe is unknown to us or we are completely wrong about the way we think the Universe works. Either way, cosmology is far from finished: we have a lot to work out."-David's comment: this also applies to string theory, around forever and no proof. Current cosmological physicists are too closed minded. And the insistence on a multiverse is of the same ilk.-The "Big Bang" (it's OK, I know it's not an explosion) as a finite start to the universe should also be seen as a theory and not a fact. A universe from nothing defies logic.

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QUOTE: "The sobering fact is that either 96 per cent of the Universe is unknown to us or we are completely wrong about the way we think the Universe works. Either way, cosmology is far from finished: we have a lot to work out."
> 
> David's comment: this also applies to string theory, around forever and no proof. Current cosmological physicists are too closed minded. And the insistence on a multiverse is of the same ilk.
> 
> dhw: The "Big Bang" (it's OK, I know it's not an explosion) as a finite start to the universe should also be seen as a theory and not a fact. A universe from nothing defies logic.-But it is expanding from something, so it seems like a good explanation. What defies logic requires God.

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QUOTE: "The sobering fact is that either 96 per cent of the Universe is unknown to us or we are completely wrong about the way we think the Universe works. Either way, cosmology is far from finished: we have a lot to work out."-David's comment: this also applies to string theory, around forever and no proof. Current cosmological physicists are too closed minded. And the insistence on a multiverse is of the same ilk.-dhw: The "Big Bang" (it's OK, I know it's not an explosion) as a finite start to the universe should also be seen as a theory and not a fact. A universe from nothing defies logic.-DAVID: But it is expanding from something, so it seems like a good explanation. What defies logic requires God.-An eternal, sourceless, conscious first-cause pure energy that knows how to create universes also defies logic. I'm afraid one illogicality does not explain another.

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> DAVID: But it is expanding from something, so it seems like a good explanation. What defies logic requires God.
> 
> dhw: An eternal, sourceless, conscious first-cause pure energy that knows how to create universes also defies logic. I'm afraid one illogicality does not explain another. - Back to requiring faith.

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Another voice stating hat dark matter is a side effect of sticking with current Einstein theories, and with an other interpretation of what is seen, dark matter is not needed:

https://aeon.co/ideas/has-dogma-derailed-the-scientific-search-for-dark-matter?utm_sour...

"According to mainstream researchers, the vast majority of the matter in the Universe is invisible: it consists of dark-matter particles that do not interact with radiation and cannot be seen through any telescope. The case for dark matter is regarded as so overwhelming that its existence is often reported as fact. Lately, though, cracks of doubt have started to appear. In July, the LUX experiment in South Dakota came up empty in its search for dark particles – the latest failure in a planet-wide, decades-long effort to find them. Some cosmic surveys also suggest that dark particles cannot be there, which is especially confounding since astronomical observations were the original impetus for the dark-matter hypothesis.

"The modern argument for dark matter begins with the assumption that the Universe is described by Albert Einstein’s field equation of general relativity, and that Newtonian gravitation (that is, gravity as we measure it on Earth) is valid in all places at all times. It further assumes that all the matter in the Universe was produced at the Big Bang. Simulations based on that scenario make specific predictions about how quickly cosmic structures form, and also about the motions of galaxies and stars within galaxies. When compared with observations, those simulations indicate that gravitational effects in the real world must be stronger than can be accounted for by the matter we know. Dark matter provides the additional gravitational pull to bring model and reality broadly into alignment. Researchers now routinely take this model – Einstein plus dark matter, often called the ‘null hypothesis’ – as their starting point and then perform detailed calculations of galactic systems to test it.

***

"The known satellite galaxies of the Milky Way are distributed in a vast polar disk running perpendicular to the orientation of our galaxy. But dark-matter dominated models predict that primordial dwarf galaxies should have fallen into the Milky Way from random directions, so should follow a spheroidal distribution. This finding set off a major debate, with the mainstream researchers arguing that this disk of satellites does not really exist; that it is not significant; or that it cannot be used to test models.

"Meanwhile, astronomers kept identifying new dwarf satellite galaxies that made the disk structure even more pronounced. Rodrigo Ibata at Strasbourg Observatory showed that our neighbouring galaxy, Andromeda, has an even more pronounced disk of satellite galaxies.

***

"The first step is that we need to revisit the validity of Newton’s universal law of gravitation. Starting in the 1980s, Mordehai Milgrom at the Weizmann Institute in Israel showed that a small generalisation of Newton’s laws can yield the observed dynamics of matter in galaxies and in galaxy clusters without dark matter. This approach is broadly known as MOND (MOdified Newtonian Dynamics). Milgrom’s correction allows gravitational attraction to fall off with distance more slowly than expected (rather than falling off with the square of distance as per Newton) when the local gravitational acceleration falls below an extremely low threshold. This threshold could be linked to other cosmological properties such as the ‘dark energy’ that accounts for the accelerating expansion of the Universe.

"These links suggest a deeper fundamental theory of space, time and matter, which has not yet been formulated. Few researchers have pursued such an alternative hypothesis, partly because it seems to question the validity of general relativity. However, this need not be the case; additional physical effects related to the quantum physics of empty space and to the nature of mass might be playing a role. MOND also faces its own challenges, both observational and theoretical. Its biggest drawback is that MOND is not yet well-anchored to general relativity. Because of the prevailing dark-matter dogma, few scientists dare to build on Milgrom’s ideas. Young researchers risk not getting a job; senior researchers face losing out on grants.

"Together with Benoit Famaey in Strasbourg, my small group in Bonn is moving ahead anyway. Yes, we are being punished by not being granted some research money, but in our computers we are discovering a universe full of galaxies that look just like the real things – and this is awfully exciting. MOND could be the next great advance in gravitational research, building on the work of Newton and Einstein. This year’s detection of gravitational waves allows exciting new possibilities. Those waves have travelled cosmological distances, and so have passed through regions where Milgrom’s low-threshold effect should be significant. Gravitational wave studies will provide the kind of data needed to refine our ideas about MOND, and to explore cosmological thinking outside the constraints of dogma."

Comment: Dark matter should not be dogma. More observations are needed. Scientific facts are not the result of a vote of a majority, but of observation and logical conclusions.

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On Thursday I replied to the following:

https://www.newscientist.com/round-up/cosmic-coincidences

QUOTE: The very early universe was dominated by dark matter. “At that time, dark matter density was 95 orders of magnitude larger than the density of dark energy,” says Nicolao Fornengo at the University of Turin, Italy.

Dhw: We don’t even know what dark matter is. You might as well say the universe was dominated by something or the other. How the heck can anyone know that the density of something or the other was 95 orders of magnitude greater than the density of another something or the other? I can’t help feeling that in the next fifty, hundred, thousand years, scientists will have come up with very different observations and explanations.

It appears that I’m not alone in my scepticism:

DAVID: Another voice stating that dark matter is a side effect of sticking with current Einstein theories, and with an other interpretation of what is seen, dark matter is not needed:
https://aeon.co/ideas/has-dogma-derailed-the-scientific-search-for-dark-matter?utm_sour...

QUOTE: "According to mainstream researchers, the vast majority of the matter in the Universe is invisible: it consists of dark-matter particles that do not interact with radiation and cannot be seen through any telescope. The case for dark matter is regarded as so overwhelming that its existence is often reported as fact. Lately, though, cracks of doubt have started to appear. In July, the LUX experiment in South Dakota came up empty in its search for dark particles – the latest failure in a planet-wide, decades-long effort to find them. Some cosmic surveys also suggest that dark particles cannot be there, which is especially confounding since astronomical observations were the original impetus for the dark-matter hypothesis.”

David’s comment: Dark matter should not be dogma. More observations are needed. Scientific facts are not the result of a vote of a majority, but of observation and logical conclusions.

Hear, hear! The big bang should not be dogma either. Theoretical physics is becoming as riddled with fantasy and dogma as religion. Mind you, I can almost hear Tony (= balancemaintained) saying the same about evolution, and of course some of Darwin’s hypotheses (random mutations, gradualism) are very shaky indeed, but common descent still seems solid to me. Anyway, many thanks for the above article, which neatly restores the balance.

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Another essay on why MOND may be the answer:

https://aeon.co/essays/we-should-explore-alternatives-to-the-standard-model-of-physics?...

"There is one problem, however. For four decades and counting, scientists have failed to detect the dark matter particles in terrestrial laboratories. You might think this would have generated some doubts about the standard cosmological model, but all indications are to the contrary. According to the 2014 edition of the prestigious Review of Particle Physics: ‘The concordance model [of cosmology] is now well established, and there seems little room left for any dramatic revision of this paradigm.’ Still, shouldn’t the lack of experimental confirmation at least give us pause?

"In fact, there are competing cosmological theories, and not all of them contain dark matter. The most successful competitor is called modified Newtonian dynamics (MOND). Observations that are explained under the Standard Model by invoking dark matter are explained under MOND by postulating a modification to the theory of gravity. If scientists had confirmed the existence of the dark particles, there would be little motivation to explore such theories as MOND. But given the absence of any detections, the existence of a viable alternative theory that lacks dark matter invites us to ask: does dark matter really exist?

***

"In three papers published in 1983, Milgrom proposed a simple modification to Isaac Newton’s laws that relate gravitational force to acceleration. (Albert Einstein’s theory reduces to Newton’s simpler theory in the regime of galaxies.) He showed that his modification correctly predicts the asymptotic flatness of orbital rotation curves.

***

"Milgrom’s hypothesis correctly predicts the rotation curve of every galaxy that has been tested in this way. And it does so without postulating the presence of dark matter.

"Note the stark difference between the way in which the two theories explain the anomalous rotation-curve data. The standard cosmological model executes an ad-hoc manoeuvre: it simply postulates the existence of whatever amount and distribution of dark matter are required to reconcile the observed stellar motions with Newton’s laws. Whereas Milgrom’s hypothesis correctly predicts orbital speeds given the observed distribution of normal matter alone. No Standard Model theorist has ever come up with an algorithm that is capable of doing anything as impressive as that.

***

"Just last year, two theorists in the Czech Republic, Constantinos Skordis and Tom Złośnik, showed that there exist fully relativistic versions of Milgrom’s hypothesis that are perfectly capable of reproducing the CMB data without dark matter. This relativistic version of MOND, which they call RMOND, incorporates an additional field that mimics the behaviour of particle dark matter on the largest cosmological scales, and yields Milgromian dynamics on the scale of galaxies.

***

"I honestly don’t know whether this troubling state of affairs reflects a general ignorance about MOND, or whether some darker psychological mechanism is at work. But I hope that scientists and educators can begin creating an environment in which the next generation of cosmologists will feel comfortable exploring alternative theories of cosmology."

Comment: It seems like we need a new paradigm about dark matter. I am no judge as to which theory might be correct. The last article prior to this one was from a group trying to study MOND, and they seemed to have trouble getting grants.

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Not like us:

https://www.sciencenews.org/article/mars-quakes-seismic-waves-red-planet-liquid-core-ha...

"Simon Stähler, a seismologist at ETH Zurich, and colleagues analyzed seismic waves from 11 marsquakes, looking for two types of waves: pressure and shear. Unlike pressure waves, shear waves can’t pass through a liquid, and they move more slowly, traveling side to side through solid materials, rather than in a push-and-pull motion in the same direction a wave is traveling like pressure waves do.

"Of those 11 events, six sets of vibrations included shear waves strong enough to stand out from background noise. The strength of those shear waves suggests that they reflected off of the outer surface of a liquid core, rather than entering a solid core and being partially absorbed, Stähler says. And the difference in arrival times at InSight for the pressure waves and shear waves for each quake suggest that Mars’ core is about 3,660 kilometers in diameter, he and colleagues report in the July 23 Science.

***

"While the newly analyzed data confirm the planet’s outer core is liquid, it’s not clear yet whether Mars has a solid inner core like Earth, says study coauthor Amir Khan, a geophysicist also at ETH Zurich. “The signal should be there in the seismic data,” he says. “We just need to locate it.”

***

"Mars’ seismic waves also hint at the thickness of the planet’s crust. As they bounce back and forth within the planet, the waves bounce off interfaces between different layers and types of rocks, says Brigitte Knapmeyer-Endrun, a seismologist at the University of Cologne in Bergisch Gladbach, Germany. In a separate study in Science, she and her team analyzed seismic signals that reflected off several such interfaces near Mars’ surface, making it difficult to determine the depth at which the planet’s crust ends and the underlying mantle begins, she says. The researchers concluded, however, that the average thickness of the crust likely lies between 24 and 72 kilometers. For comparison, Earth’s oceanic crust is about 6 to 7 kilometers thick, while the planet’s continental crust averages from 35 to 40 kilometers thick. (my bold)

***

"The findings could also provide insights that would help planetary scientists better understand how Mars formed and evolved over the life of the solar system, and how the Red Planet ended up so unalike Earth,..."

Comment: Mars is so unlike Earth, the thick crust would not allow the subduction process that helps create conditions supporting life on Earth.

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Now found second time from black holes:-https://www.newscientist.com/article/mg23030783-800-ligo-sees-new-gravitational-wave-from-more-doomed-black-holes/-"The LIGO team made history in February when they announced the first detection of gravitational waves. Albert Einstein predicted they would be produced when massive objects like black holes move around. Dubbed GW150914, the signal arrived at twin detectors in Hanford, Washington, and Livingston, Louisiana, on 14 September last year. 
 
"The detectors picked up the minuscule stretching of space-time spurred by the collision of a pair of black holes about 30 and 35 times the mass of the sun, 1.3 billion light years away.-"The second signal, called GW151226, also came from a pair of black holes merging. But these were much lighter - about 14.2 and 7.5 times the mass of the sun. They merged to form a black hole of 20.8 solar masses, meaning about 1 solar mass of energy radiated away in gravitational waves during the collision.-'This event radiated the equivalent of the mass of our sun in a couple of seconds, Vitale says. Our own sun radiated about a millionth of its mass in 5 billion years. This really gives you the scale of how violent and sudden this release of energy is, as compared to our everyday experience.-"If you could see it, the collision would be 10,000 times brighter than a gamma-ray burst, the brightest explosions we know of in the universe, says Avi Loeb at Harvard University.-***-"When we made the first discovery, it was kind of surprising because they have zero overlap with the known distribution of black holes, Vitale says. Now we are back on two black holes with masses that are totally compatible with what we expect. It's nice to see that we can target a similar population.-"It also meant that LIGO watched more of their deadly waltz. The black holes in the first event were so massive that they swung around each other less than 10 times before merging. In the second collision, the team watched 55 full orbits before the end.-***-"When we made the first discovery, it was kind of surprising because they have zero overlap with the known distribution of black holes, Vitale says. Now we are back on two black holes with masses that are totally compatible with what we expect. It's nice to see that we can target a similar population.-"It also meant that LIGO watched more of their deadly waltz. The black holes in the first event were so massive that they swung around each other less than 10 times before merging. In the second collision, the team watched 55 full orbits before the end.-*** 
"But the signal from the smaller black holes was also more difficult to detect. The first one was so powerful that you could see it in the data with the naked eye. You could even hear it: translating the signal into sound waves gave a chirp, a rise in pitch and volume as the black holes circle each other faster and faster.-"This new one required more targeted algorithms and sophisticated processing, to tease the signal out of the noise.-***-"Regardless, seeing more cycles makes this system a better laboratory to test Einstein's theory of general relativity.-'If there is any small deviation from general relativity, it will accumulate, Vitale says. If you have more cycles you have a better hope to see if there is something wrong. So far, the event matches general relativity perfectly.-"The team also measured a new attribute of the black holes: one of the behemoths was spinning slowly.-"Measuring spin is a way to probe how the black holes formed. If they came from a pair of stars that both exploded and became black holes together, they ought to spin in the same direction. If they were already black holes when they found each other in a dense environment like a globular cluster, they should not.-"More detections will help gauge the size of the universe, probe the nature of matter and test general relativity to ever higher precision."-Comment: Fabulous science.-------
 -- - -But the signal from the smaller black holes was also more difficult to detect. The first one was so powerful that you could see it in the data with the naked eye. You could even hear it: translating the signal into sound waves gave a chirp, a rise in pitch and volume as the black holes circle each other faster and faster.-This new one required more targeted algorithms and sophisticated processing, to tease the signal out of the noise.

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Planets close to their star (sun) get locked in tug of war with their sun and rotate only once in each orbit just like our moon, which is tidally locked and we only see one side all of the time. This article describes the phenomenon and wonders if such planets might have life of some sort: - http://nautil.us//blog/forget-earth_likewell-first-find-aliens-on-eyeball-planets - " There is good reason to think that the first potentially life-bearing worlds that are now being detected around other stars (see here for example) probably look very different than Earth. Rather, these planets are more likely to look like giant eyeballs whose gaze is forever fixed on their host stars (which is not something I recommend doing with your own eyeballs). - " The sweet spot for finding a habitable planetwith the same temperature as Earthis on a much smaller orbit than Earth's around a star much fainter than the Sun. But there are consequences of having a smaller orbit. A planet close to its star feels strong tides from its star, like the tides Earth feels from the Moon, but much stronger. Strong tides change how a planet spins. Tides drive the planet's obliquity to zero, meaning that the planet's equator is perfectly aligned with its orbit. The planet will also be tidally locked: It always shows the same side to the star. - *** - " .. the Sun would remain fixed in one spot on the sky. The hemisphere facing the star is in constant daylight and the far hemisphere in constant darkness. In between lies a ring of eternal sunset, quite possibly the most romantic place in the Universe. The hottest part of the planet is the location where the star is directly overhead (the substellar point in astro-speak). ... But on a tidally locked planet the Sun stays in the same place in the sky and the hot spot never moves. This creates visible differences across the planet's surface; the relatively small hot spot is the pupil of an eyeball planet. - "Eyeball planets come in all sorts of flavors, depending on the conditions. We are going to take a look at two examples: hot eyeball and icy eyeball planets. A hot eyeball planet is located close to its star, on an orbit that makes it hotter overall than Earth. It is blazing on the day side and deathly cold on the night side. The planet's water is boiled on the day side and frozen on the night side. But winds transport the water vapor from the day side toward the night side to freeze. This can create a cold trap: all of the planet's water can be locked up in a giant layer of ice on the permanent-night side. Dry day side, ice-covered night side. - "When a layer of ice gets thick enough, its bottom layer melts from the pressure. This causes the ice to flow downhill, like glaciers do on Earth. So a hot eyeball planet's thick night side ice cap spreads out and slowly flows toward the day side. There may be a trickle of water that flows into the light to be evaporated all over again. Our models project that there are characteristic wind patterns that pile clouds up in a specific region on the night side. Rivers that flow from the night side to eventually evaporate on the day side might even look like veins. - "Where on a hot eyeball planet could you live? The day side is roasting and dry. The night side is frigid and icy. In between, it's just right! The sweet spotlet's call it the ring of lifeis at the terminator, the boundary between night and day. The ring of life is bounded by deserts on one side and ice on the other. There is a constant flow of water from the night side to the day sidea series of rivers, all flowing in the same direction. The Sun is fixed in the sky right at the horizon, and the area is in permanent light. Conditions are pretty much the same all the way across the ring of life. - *** - "Icy eyeballs are also tidally locked to their stars, though their orbits are larger than those of hot eyeball planets, and heat is in short supply. What icy eyeball planets do have is an abundance of waterthe night side is covered in ice, and there is enough stellar heating at the substellar point for water to remain liquid. There is essentially a large pond in the midst of a global icy landscape. Below the surface ice, the ocean covers the entire globe. - " Where would you want to live on an icy eyeball planet? Underwater life could exist throughout the subsurface ocean, but surface life that relies on liquid water would need to stay near the pond. Yet the conditions near the substellar point would be extreme: strong stellar irradiation in the midst of barren icy landscape. The best place to live would probably be by the icy shore of the pond, and it would definitely be advantageous to be amphibious (evolution, anyone?). - *** - "Hot eyeball and icy eyeball planets are extreme cases, but any planet that is tidally locked to its star is likely to look very different on its day side and its night side. Differences could come from clouds clustered in certain areas, from preferential melting of ice on the day side or freezing of ice on the night side, or from any number of other possible sources. The galaxy may be littered with wild varieties of eyeball planets! The search for life on other planets will almost certainly start with these worlds." - Comment: The planet recently found by a star very close to us is likely tidally bound. Any life on planets like this would likely be very primitive. See the article for diagrammatic pictures of the concept.

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The star close to us with a planet is discussed: - http://nautil.us/blog/our-nearest-star-has-a-planet-and-these-are-the-ways-it-could-be-... - "The discovery of Proxima b, announced today, has motivated a handful of in-depth studies. I was involved with two that address the question of whether Proxima b could really be habitable. I'm not about to buy any real estate there, but, as far as I can tell, there are reasons to be optimistic. - 
"The biggest difference between Proxima b and Earth are their stars: They have drastically different histories, and futures. Our sun is a bright, lazy yellow star that will, in about 5 billion years, become a hostile red giant, subsuming Earth's orbit. Proxima Centauri, on the other hand, is a fidgety red dwarf only about 10 percent as massive as the sun and 1/700th as bright; it'll be friendly to Proxima b for another 4 trillion years. Though Earth and Proxima b receive a similar amount of energy, in the form of starlight, growing up in Proxima's neighborhood is much more of a challengelike the difference between a gang-ridden inner city and an affluent suburban cul-de-sac. Proxima b's orbit is only 5 percent as wide as Earth's, and its year is only 11 days long. - *** - "When rocky planets get cooked like this, potentially life-bearing Earths can turn into dry, inhospitable Venuses. Did this happen to Proxima b? We modeled this process in one of our studies. We found that, before reaching the habitable zone, Proxima b could have lost up to 1 Earth ocean of water (the amount of water on Earth's surface) to evaporation. But it may also have an additional source of water trapped in the mantle; Earth, for example, has roughly between 0.3 and 10 Earth oceans underneath the surface. If our oceans were suddenly zapped into space, water would be replenished to some degree by outgassing from volcanoes. - *** - "Earth, as you may have noticed, spins fast365 times for every orbit of the sun. Proxima b, by contrast, is so close to its star that tides limit the planet's spin to two possibilities. Proxima b could be rotating synchronously, always showing the same face to the star, as the moon does to Earth; or Proxima b could be locked in a spin-orbit resonance, spinning exactly three times for every two orbits, like Mercury. The planet is definitely in one of these states but we don't know which. - *** - "So the punch line is that Proxima b can retain liquid water on its surface for a wide range of conditionsbut only if it held on to some water while its star went through its youthful tantrums. Another potential obstacle to habitability is the amount of energetic radiation Proxima b receives compared to Earth: 250 times more X-rays and 30 times more extreme ultraviolet light. What this means for the planet's atmosphere is unclear, but it's probably not a deal-breaker for life. - 
"This is the planet we have been waiting for." - Comment: Long theoretical article using our knowledge of our solar system and how planets evolved and assumed their positions, then applied to this planet. It will provide lots of material for study, which is why the author is so excited. Many explanations and diagrams to be read if interested.

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The star close to us with a planet is discussed:
> 
> http://nautil.us/blog/our-nearest-star-has-a-planet-and-these-are-the-ways-it-could-be-... 
> 
> "This is the planet we have been waiting for."-No it isn't deserving the hype about Earth-like. But it is worth studying:-http://mashable.com/2016/08/28/earth-like-planets-proxima-b/#hANc6Te1Emq4-"The discovery of a new, possibly habitable alien planet is always met by media coverage marked by sweeping pronouncements about our place in the universe, and even *gasp* alien life.-"Wednesday's announcement of a newfound, possibly Earth-sized planet in a potentially habitable orbit around a star not far from our sun threw that kind of breathless coverage into overdrive. -***-"Yes, it's amazing that this possibly rocky planet is orbiting a star just 4 light-years away, possibly close enough to one day launch a mission to, but there is still so much we don't know about this brave new world.-
"Plus, Proxima b is far from being a twin of our planet. -"Scientists aren't sure what kind of atmosphere it has or even if it's able to support a magnetic field, two things that it would need to sustain habitability in orbit around its active, flaring star. -"We simply don't know if it can support water, life or much of anything on its surface at all.-"Beyond the inaccuracy in this particular case, calling a planet "Earth-like" without knowing if it actually is, threatens to give members of the public a false sense of just how unique (or average) our Earth is.-***-"Why not save the Earth-like label for something that truly is?-"'If we say Earth-like in every press release, it kind of cheapens it in a way," NASA exoplanet scientist Steve Howell told Mashable in an interview. -"And he would know. For years, Howell has worked with NASA's Kepler Space Telescope  which searches for alien worlds out in the universe. -***-"In the next 10 to 20 years, more and more huge telescopes on Earth will start coming online, allowing scientists to scan the heavens for signs of life and pleasant atmospheres on close-by alien worlds. Proxima b will likely be a great target for that kind of followup research.-
"Plus, NASA's James Webb Space Telescope is due to launch in 2018, possibly providing new views of alien atmospheres that could pick up possible biosignatures  like oxygen  floating around on those worlds.-"But until then, we'll probably have to keep on waiting before we call anything truly "Earth-like.'"-Comment: My sentiments exactly.

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Gravitational evidence says its there, but what is it? We don't know what energy particles are involved:-http://www.scientificamerican.com/article/physics-confronts-its-heart-of-darkness/-"The latest, most sensitive searches for the particles thought to make up dark matterthe invisible stuff that may comprise 85 percent of the mass in the cosmoshave found nothing. Called WIMPs (weakly interacting massive particles), these subatomic shrinking violets may simply be better at hiding than physicists thought when they first predicted them more than 30 years ago. Alternatively, they may not exist, which would mean that something is woefully amiss in the underpinnings of how we try to make sense of the universe.-***-"Whatever dark matter is, it is not accounted for in the Standard Model of particle physics, a thoroughly-tested theory of almost everything forged in the 1970s that explains all known particles and all known forces other than gravity. Find the identity of dark matter and you illuminate a new path forward to a deeper understanding of the universeat least, that is what physicists hope.-***-"One of the latest null results in the search for WIMPs came from the Large Underground Xenon (LUX) experiment, a third of a ton of liquid xenon held at a frosty -100 degrees Celsius inside a giant water-filled tank buried one and a half kilometers beneath the Black Hills of South Dakota. There, shielded from most sources of contaminating noise, researchers have spent more than a year's worth of time looking for flashes of light emanating from WIMPs striking xenon nuclei. On July 21 they announced they had seen none.-***-"We are now more in the dark about dark matter than we were five years ago, he says. So far, Kolb says, most theorists have responded by letting a thousand WIMPs bloom, creating ever-more baroque and exotic theories to explain how WIMPs have managed to dodge all our detectors.-***-"Gaitskell and other WIMP hunters are betting that bigger detectors will yield better results, and have plans for a new generation of experiments with dramatically larger sizes and sensitivities. I started looking 28 years ago using a 10-gram detector, Gaitskell says. Today we're using a detector that is a third of a ton of liquid xenon. And within the next 10 to 15 years we will look with detectors that are 100 tons.-***-"Many supersymmetry theories predict the lightest superpartner would be a stable, neutral, weakly interacting particlethat is, a WIMP. This is the phantom particle the LHC has been seekingand failing to findin its latest collisions. It's remarkable how these two entirely separate lines of evidence converge to tell you these particles can exist and give you the right kind and amount of dark matter, says Neal Weiner, a dark matter theorist at New York University. That's the WIMP miracle.-***-"Feng and many others propose that WIMPs are part of a much more complicated picture: An entirely new hidden realm of the universe filled with multiple varieties of dark particles interacting with one another through a suite of dark forces, perhaps exchanging dark charges via bursts of dark light. Because they offer theorists many more variables to play with, such dark sector models can be reconciled to fit into the ever-tighter straitjacket of facts placed on dark matter by new data.-***-'Now that we have lost the guidance from the WIMP miracle, the space of available models is huge. It's a playground where we don't know what the right choices arewe now need more hints from nature about where to go next.-***-"Last year a team of researchers won a Nobel Prize for discovering that ghostly, weakly interacting particles called neutrinos come in three flavors and possess mass. The three neutrino varieties are not massive enough to account for dark matter, but by virtue of having mass at all they open the possibility for the existence of a fourtha massive, so-called sterile neutrino.-***
"For axions to explain dark matter, they would need to occupy a relatively narrow range of masses and be far lighter than WIMPs, potentially making them even harder to detect. If we don't find the WIMP, theorists will just switch their bets to axions, -***-'The desire is for dark matter to not only exist but also to solve other outstanding problems of the Standard Model, says Jesse Thaler, a physicist at Massachusetts Institute of Technology. Not every new discovery can be a revelation like the Higgs, where afterward theories suddenly fit together much better. Sometimes new particles just make you say, Who ordered that?' Do we live in a universe where each discovery leads to deeper, more fundamental insights or do we live in one where some parts have rhyme and reason but others don't? Dark matter offers either possibility.'-Comment: We are the same point we were in the 1950's, not knowing exactly what might turn up. The Higgs that appeared was not as heavy as expected, but fits. New knowledge is over the horizon again.

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DAVID: Gravitational evidence says its there, but what is it? We don't know what energy particles are involved:-http://www.scientificamerican.com/article/physics-confronts-its-heart-of-darkness/-QUOTE: "The latest, most sensitive searches for the particles thought to make up dark matterthe invisible stuff that may comprise 85 percent of the mass in the cosmoshave found nothing. Called WIMPs (weakly interacting massive particles), these subatomic shrinking violets may simply be better at hiding than physicists thought when they first predicted them more than 30 years ago. Alternatively, they may not exist, which would mean that something is woefully amiss in the underpinnings of how we try to make sense of the universe." (My bold)-QUOTE: "Whatever dark matter is, it is not accounted for in the Standard Model of particle physics, a thoroughly-tested theory of almost everything forged in the 1970s that explains all known particles and all known forces other than gravity. Find the identity of dark matter and you illuminate a new path forward to a deeper understanding of the universeat least, that is what physicists hope. (My bold)-As always, thank you for your integrity in posting articles which often seem to run counter to your own arguments. Here we have physicists acknowledging that the Standard Model is unable to account for gravity and 85% of the mass in the cosmos. 15% apparently = "almost everything", and by definition we have no idea what or how many unknown particles exist. The current pattern, which earlier you said strongly suggests there is a mind behind it, may therefore be woefully amiss. But of course, no matter what patterns are found, you will argue that they strongly suggest the mind of God! You may be rightyou may be wrong. Who knows? As somebody wrote only recently, in defence of a different hypothesis from your own: There are VAST gaps in our knowledge, and that is precisely why the rest of the stuff HAS to be theoretical imagination, and why my hypothesis is no more and no less likely than any other.

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> As always, thank you for your integrity in posting articles which often seem to run counter to your own arguments. Here we have physicists acknowledging that the Standard Model is unable to account for gravity and 85% of the mass in the cosmos. 15% apparently = "almost everything", and by definition we have no idea what or how many unknown particles exist. The current pattern, which earlier you said strongly suggests there is a mind behind it, may therefore be woefully amiss. -Once more, the article accepts that the Higgs discovery completed an anticipated pattern. You are railing about what we don't know beyond the pattern. Gravity never fit the pattern. It is one of the existing puzzles outside of it. A pattern which allows predictions suggest it was planned. And minds plan.

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dhw: As always, thank you for your integrity in posting articles which often seem to run counter to your own arguments. Here we have physicists acknowledging that the Standard Model is unable to account for gravity and 85% of the mass in the cosmos. 15% apparently = "almost everything", and by definition we have no idea what or how many unknown particles exist. The current pattern, which earlier you said strongly suggests there is a mind behind it, may therefore be woefully amiss. -DAVID: Once more, the article accepts that the Higgs discovery completed an anticipated pattern. You are railing about what we don't know beyond the pattern. Gravity never fit the pattern. It is one of the existing puzzles outside of it. A pattern which allows predictions suggest it was planned. And minds plan.-We have agreed that the Higgs completed a segment of a pattern. However, it is clear that the next segment of the pattern entailed the prediction of WIMPS, and since the prediction has so far failed to come true, the researchers tell us they may not exist, which would mean that something is woefully amiss in the underpinnings of how we try to make sense of the universe." If the Standard Model is our current means of making sense of the universe, it may be that the Standard Model is woefully amiss - but as I keep saying that will not stop you from claiming that any pattern is planned, even if a whole raft of unpredicted particles should emerge from the quest for dark matter.
 
As for fulfilled predictions suggesting that the pattern was planned, there are weather patterns which allow meteorologists to make predictions, but owing to the fact that these patterns are as incomplete as the Standard Model, the predictions are often woefully amiss. I doubt if even you would claim that when weather forecasts are right, they strongly suggest a planning mind. It may even be that the complete pattern of the universe is as changeable as that of the weather, with both predictable and unpredictable elements.

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> dhw: We have agreed that the Higgs completed a segment of a pattern.-No we haven't. What I have said is the Higgs finished an anticipated pattern. We have no idea what comes next, whether it is an extension of the pattern we see or a totally different pattern but related.-> dhw: However, it is clear that the next segment of the pattern entailed the prediction of WIMPS,-No it didn't. The Higgs was anticipated! The Wimps are totally theoretical, not anticipated.-> dhw: If the Standard Model is our current means of making sense of the universe, it may be that the Standard Model is woefully amiss -It is not woefully amiss. It is a perfect explanation of the particles we have found, no more. Your persistent view is as if you understand the geography of England and think it should help to explain the entire Earth. You may be an Anglophile, but it doesn't work that way.
> 
> dhw: It may even be that the complete pattern of the universe is as changeable as that of the weather, with both predictable and unpredictable elements.-YES! Remember the quote, 'who ordered that". Later the muons fit in.

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This article makes my position about the Standard model quite clear. It is complete, a fully understood segment, but now theorists are guessing at new possibilities for dark matter, which must be another step in our understanding the makeup of the universe by its particles. A new boson is suggested by current observations:-http://phys.org/news/2016-09-scientists-boson-madala-dark.html-"Using data from a series of experiments that led to the discovery and first exploration of the Higgs boson at the European Organization for Nuclear Research (CERN) in 2012, the group established what they call the Madala hypothesis, in describing a new boson, named as the Madala boson. The experiment was repeated in 2015 and 2016, after a two-and-a-half year shut-down of the Large Hadron Collider (LHC) at CERN. The data reported by the LHC experiments in 2016 have corroborated the features in the data that triggered the Madala hypothesis in the first place.-"'Based on a number of features and peculiarities of the data reported by the experiments at the LHC and collected up to the end of 2012, the Wits HEP group in collaboration with scientists in India and Sweden formulated the Madala hypothesis," says Professor Bruce Mellado, team leader of the HEP group at Wits.-"The hypothesis describes the existence of a new boson and field, similar to the Higgs boson. However, where the Higgs boson in the Standard Model of Physics only interacts with known matter, the Madala boson interacts with Dark Matter, which makes about 27% of the Universe.-"'Physics today is at a crossroads similar to the times of Einstein and the fathers of Quantum Mechanics," says Mellado. "Classical physics failed to explain a number of phenomena and, as a result, it needed to be revolutionised with new concepts, such as relativity and quantum physics, leading to the creation of what we know now as modern physics."-"The theory that underpins the understanding of fundamental interactions in nature in modern physics is referred to as the Standard Model of Physics. With the discovery of the Higgs boson at the LHC in 2012, for which the Nobel Prize in Physics was awarded in 2013, the Standard Model of Physics is now complete. However, this model is insufficient to describe a number of phenomena such as Dark Matter. (my bold)-"The universe is made of mass and energy. The mass that we can touch, smell and see, the mass that can be explained by the Higgs boson, makes up only 4% of the mas-energy budget of the Universe. The rest of the mass in the Universe is simply unknown, yet it makes about 27% of the world around us. The next big step for the physics of fundamental interactions now is to understand the nature of Dark Matter in the Universe: what is it made of? How many different types of particles are there? How do they interact among each other? How does it interact with the known matter? What can it tell us about the evolution of the Universe?-"The discovery of the Higgs boson at the LHC at CERN has opened the door into making even more ground-breaking discoveries, such as the observation of new bosons that are linked to forces and particles unknown before. These new particles can explain where the unknown matter in the Universe comes from."-Comment: Note my bold. The Standard Model (SM) is complete and so fully understood, Higgs could make his prediction 32 years ago and it was fully expected to be found. Leon Lederman called it "The God Particle" in his book, 1993. This completes our knowledge of visible matter only. How the SM will relate to dark matter is to be discovered, but it is a completely discrete step requiring discovery and then an analysis for complete understanding of a new segment.

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So far the LHC at very high energies has produced no super particles, which had bern expected. Where does that leave us?:-https://www.sciencenews.org/article/supersymmetry%E2%80%99s-absence-lhc-puzzles-physicists?tgt=nr-"For decades, many particle physicists have devoted themselves to the beloved theory, known as supersymmetry. But it's beginning to seem that the zoo of new particles that the theory predicts the heavier cousins of known particles  may live only in physicists' imaginations. Or if such particles, known as superpartners, do exist, they're not what physicists expected.-"New data from the world's most powerful particle accelerator  the Large Hadron Collider, now operating at higher energies than ever before  show no traces of superpartners. -***-"Whether their pet theories are right or wrong, many theoretical physicists are simply excited that the new LHC data can finally anchor their ideas to reality. Of course, in the end, nature is going to tell us what's true, says theoretical physicist Yonit Hochberg -***-"Supersymmetry is not ruled out by the new data, but if the new particles exist, they must be heavier than scientists expected. Right now, nature is telling us that if supersymmetry is the right theory, then it doesn't look exactly like we thought it would, Hochberg says.-***-"the LHC, at the European particle physics lab CERN near Geneva, has been smashing protons together at higher energies than ever before: 13 trillion electron volts. Physicists had been eager to see if new particles would pop out at these energies. But the results have agreed overwhelmingly with the standard model, the established theory that describes the known particles and their interactions.-"It's a triumph for the standard model, but a letdown for physicists who hope to expose cracks in that theory. There is a low-level panic, says theoretical physicist Matthew Buckley. We had a long time without data, and during that time many theorists thought up very compelling ideas. And those ideas have turned out to be wrong. (my bold)-"Physicists know that the standard model must break down somewhere. It doesn't explain why the universe contains more matter than antimatter, and it fails to pinpoint the origins of dark matter and dark energy, which make up 95 percent of the matter and energy in the cosmos.(my bold)-"Even the crowning achievement of the LHC, the discovery of the Higgs boson in 2012 (SN: 7/28/2012, p. 5), hints at the sickness within the standard model. The mass of the Higgs boson, at 125 billion electron volts, is vastly smaller than theory naïvely predicts. That mass, physicists worry, is not natural  the factors that contribute to the Higgs mass must be finely tuned to cancel each other out and keep the mass small. (my bold)-"Supersymmetry solves three major problems in physics: It explains why the Higgs is so light; it provides a particle that serves as dark matter; and it implies that the three forces of the standard model (electromagnetism and the weak and strong nuclear forces) unite into one at high energies.-"If a simple version of supersymmetry is correct, the LHC probably should have detected superpartners already. As the LHC rules out such particles at ever-higher masses, retaining the appealing properties of supersymmetry requires increasingly convoluted theoretical contortions, stripping the idea of some of the elegance that first persuaded scientists to embrace it.-***-"The lack of new particles forces theoretical physicists to consider new explanations for the mass of the Higgs. To be consistent with data, those explanations can't create new particles the LHC should already have seen.-"Some physicists  particularly those of the younger generations  are ready to move on to new ideas. I'm personally not attached to supersymmetry, says David Kaplan of Johns Hopkins University. Kaplan and colleagues recently proposed the relaxion hypothesis, which allows the Higgs mass to change  or relax  as the universe evolves. Under this theory, the Higgs mass gets stuck at a small value, never reaching the high mass otherwise predicted.-***-"One particularly controversial idea is the multiverse hypothesis. There may be innumerable other universes, with different Higgs masses in each. Perhaps humans observe such a light Higgs because a small mass is necessary for heavy elements like carbon to be produced in stars. People might live in a universe with a small Higgs because it's the only type of universe life can exist in. (my bold) -"It's possible that physicists' fears will be realized  the LHC could deliver the Higgs boson and nothing else. Such a result would leave theoretical physicists with few clues to work with. Still, says Hochberg, if that's the case, we'll still be learning something very deep about nature.'-Comment: Note my bolded statements. The Standard Model is very consistent as far as it goes. It may not go further. We don't know what we don't know, and what is found in the future may not fit current predictions. This has happened in the past. In this article fine tuning pops out in regard to the small Higgs.

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We know how very light carbon is made in stars. How about the heavy ones?

https://phys.org/news/2020-03-physicists-heavy-elements.html

"A long-held mystery in the field of nuclear physics is why the universe is composed of the specific materials we see around us. In other words, why is it made of "this" stuff and not other stuff?

"Specifically of interest are the physical processes responsible for producing heavy elements—like gold, platinum and uranium—that are thought to happen during neutron star mergers and explosive stellar events.

"Scientists from the U.S. Department of Energy's (DOE) Argonne National Laboratory led an international nuclear physics experiment conducted at CERN, the European Organization for Nuclear Research, that utilizes novel techniques developed at Argonne to study the nature and origin of heavy elements in the universe. The study may provide critical insights into the processes that work together to create the exotic nuclei, and it will inform models of stellar events and the early universe.

***

"At these magic numbers, of which 8, 20, 28, 50 and 126 are canonical values, nuclei have enhanced stability, much as the noble gases do with closed electron shells. Nuclei with neutrons above the magic number of 126 are largely unexplored because they are difficult to produce. Knowledge of their behavior is crucial for understanding the rapid neutron-capture process, or r-process, that produces many of the heavy elements in the universe.

"The r-process is thought to occur in extreme stellar conditions such as neutron-star mergers or supernovae. These neutron rich environments are where nuclei can rapidly grow, capturing neutrons to produce new and heavier elements before they have chance to decay. (my bold)

***

"'No other facility can make mercury beams of this mass and accelerate them to these energies," said Kay. "This, coupled with the outstanding resolving power of the ISS, allowed us to observe the spectrum of excited states in 207Hg for the first time."

"The ISS is a newly-developed magnetic spectrometer that the nuclear physicists used to detect instances of 206Hg nuclei capturing a neutron and becoming 207Hg. The spectrometer's solenoidal magnet is a recycled 4-Tesla superconducting MRI magnet from a hospital in Australia. It was moved to CERN and installed at ISOLDE, thanks to a UK-led collaboration between University of Liverpool, University of Manchester, Daresbury Laboratory and collaborators from KU Leuven in Belgium.

"Deuterium, a rare heavy isotope of hydrogen, consists of a proton and neutron. When 206Hg captures a neutron from the deuterium target, the proton recoils. The protons emitted during these reactions travel to the detector in the ISS, and their energy and position yield key information on the structure of the nucleus and how it is bound together. These properties have a significant impact on the r-process, and the results can inform important calculations in models of nuclear astrophysics.

***

"The first analyses of the data from the CERN experiment confirm the theoretical predictions of current nuclear models, and the team plans to study other nuclei in the region of 207Hg using these new capabilities, giving deeper insights into the unknown regions of nuclear physics and the r-process."

Comment: very technical paper, but we are learning to answer the question as to why we have 92 natural elements from hydrogen to uranium. dhw asks the question today in another thread wondering why the universe is so big and has such weird parts. To make our elements is one new answer. He asks the question as if God didn't know what He was doing. (Tuesday, March 31, 2020, 11:05)

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They deliver elements to us:

https://phys.org/news/2020-03-electron-eating-neon-star-collapse.html

"An international team of researchers has found that neon inside a certain massive star can consume the electrons in the core, a process called electron capture, which causes the star to collapse into a neutron star and produce a supernova.

***

"An eight- to 10-solar-mass star commonly forms a core composed of oxygen, magnesium and neon (figure 1). The core is rich in degenerate electrons, meaning there is an abundance of electrons in a dense space with high enough energy to sustain the core against gravity. Once the core density is high enough, the electrons are consumed by magnesium and then neon, which are also found inside the core. Past studies have confirmed that magnesium and neon can start eating away at the electrons once the mass of the core has grown close to Chandrasekhar's limiting mass, a process called electron capture, but there has been debate about whether electron capture can cause neutron star formation. A multi-institutional team of researchers studied the evolution of an 8.4-solar-mass star and ran computer simulations on it to find an answer.

"Using newly updated data by Suzuki for density-dependent and temperature-dependent electron capture rates, they simulated the evolution of the star's core, which is supported by the pressure of degenerate electrons against the star's own gravity. As magnesium and mainly neon eat the electrons, the number of electrons decreased and the core rapidly shrunk.

"The electron capture also released heat. When the central density of the core exceeded 1010 g/cm3, oxygen in the core started to burn materials in the central region of the core, turning them into iron-group nuclei such as iron and nickel. The temperature became so hot that protons became free and escaped. Then the electrons became easier to capture by free protons and iron-group-nuclei, and the density was so high that the core collapsed without producing a thermonuclear explosion.

"With the new electron capture rates, oxygen burning was found to take place slightly off-center. Nevertheless, the collapse formed a neutron star and caused a supernova explosion, showing that an electron-capture supernova can occur.

"A certain mass range of stars with eight to 10 solar masses would form white dwarfs composed of oxygen-magnesium-neon by envelope loss due to stellar wind mass loss. If the wind mass loss is small, on the other hand, the star undergoes the electron capture supernova, as found in their simulation."

Comment: Same observation. God created a universe He knew He needed to give us the elements we need and use. dhw: wonders why the universe is like it is. ( Tuesday, March 31, 2020, 11:05)

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dhw: We have agreed that the Higgs completed a segment of a pattern.
DAVID: No we haven't. What I have said is the Higgs finished an anticipated pattern. We have no idea what comes next, whether it is an extension of the pattern we see or a totally different pattern but related.-DAVID (under a new dark matter boson): This article makes my position about the Standard model quite clear. It is complete, a fully understood segment, but now theorists are guessing at new possibilities for dark matter, which must be another step in our understanding the makeup of the universe by its particles. (Dhw's bold)-If the Standard Model is a complete, fully understood segment (of what, if not of a pattern?), why do you tell me that we have not agreed that the Higgs completed a segment of a pattern?
 
dhw: However, it is clear that the next segment of the pattern entailed the prediction of WIMPS
DAVID: No it didn't. The Higgs was anticipated! The Wimps are totally theoretical, not anticipated.-QUOTE: The latest, most sensitive searches for the particles thought to make up dark matterthe invisible stuff that may comprise 85 percent of the mass in the cosmoshave found nothing. Called WIMPs (weakly interacting massive particles), these subatomic shrinking violets may simply be better at hiding than physicists thought when they first predicted them more than 30 years ago. (My bold)-When is a prediction not a prediction? -dhw: If the Standard Model is our current means of making sense of the universe, it may be that the Standard Model is woefully amiss. 
DAVID: It is not woefully amiss. It is a perfect explanation of the particles we have found, no more.
 
QUOTE: "Physicists know that the standard model must break down somewhere. It doesn't explain why the universe contains more matter than antimatter, and it fails to pinpoint the origins of dark matter and dark energy, which make up 95 percent of the matter and energy in the cosmos.(David's bold)
"Even the crowning achievement of the LHC, the discovery of the Higgs boson in 2012 (SN: 7/28/2012, p. 5), hints at the sickness within the standard model[/b]. (David's bold)-David's comment: Note my bolded statements. The Standard Model is very consistent as far as it goes. It may not go further. We don't know what we don't know, and what is found in the future may not fit current predictions. -I have noted your bolded statements, which repeat other quotes saying that the SM may be defective, we agree that the SM is a completed segment, and we agree that we have no idea what pattern may emerge in the future when research delves into other segments of the pattern. Why all this vehement opposition to statements of mine which you then proceed to echo?-dhw: It may even be that the complete pattern of the universe is as changeable as that of the weather, with both predictable and unpredictable elements.
DAVID: YES! Remember the quote, 'who ordered that". Later the muons fit in.
-At last a yes!

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David's comment: Note my bolded statements. The Standard Model is very consistent as far as it goes. It may not go further. We don't know what we don't know, and what is found in the future may not fit current predictions. 
> 
> dhw: I have noted your bolded statements, which repeat other quotes saying that the SM may be defective, we agree that the SM is a completed segment, and we agree that we have no idea what pattern may emerge in the future when research delves into other segments of the pattern. Why all this vehement opposition to statements of mine which you then proceed to echo?-I have sensed a nuance of difference in your thinking from mine. But it now appears we have coalesced into the same point of view. See below.
> 
> dhw: It may even be that the complete pattern of the universe is as changeable as that of the weather, with both predictable and unpredictable elements.
> DAVID: YES! Remember the quote, 'who ordered that". Later the muons fit in.
> 
> 
> dhw: At last a yes!

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Another commentary on not finding WIMPS to explain dark matter:-http://www.livescience.com/56041-dark-matter-just-got-murkier.html?utm_source=ls-newsletter&utm_medium=email&utm_campaign=20160909-ls-"The most recent contribution to our knowledge of dark matter was made by the Large Underground Xenon (LUX) collaboration. LUX is a vessel consisting of a third of a ton of liquid xenon and it is the most powerful dark-matter detector ever constructed.......And the thing is, it didn't detect anything. That non-discovery is what's causing physicists to rethink how they think about dark matter.-***-"We have never directly observed dark matter, but we know a great deal about what it must be: It must be massive (because it affects the rotation of galaxies); it must be electrically neutral (because we can't see it); it must be different from ordinary matter (because we see no evidence for it interacting with matter in the usual ways); and it must be stable (because it has existed since the dawn of the universe). These properties are unequivocal.-***- "It is the heavy mass and non-interacting qualities that make the sterile neutrino an ideal dark-matter candidate.-"Another possible dark-matter particle, the axion, was proposed in 1977 as a way to ensure that the strong nuclear force treated matter and antimatter on equal footing (so as agree with observations). The axion is a very light, but still massive, hypothetical particle. The LUX detector is not designed to study axions.-"Then, of course, there is the even more creative hypothesis, which suggests that dark matter isn't a single, neutral, non-interacting particle. After all, ordinary matter is pretty complicated. At the quantum scale, we have quarks and leptons and four forces. At the macro scale, we have you and me and sugar and stars and volcanoes and all the various ways they interact. Ordinary matter has all sorts of interactions and constituents. Why not dark matter?-***-"It's not fair to say that the LUX measurement leads to a crisis in particle physics and cosmology. But it certainly gives scientists pause and suggests that maybe we should take another look at this WIMP thing. Maybe other ideas need to be revisited. On the other hand, scientists who want to continue to pursue the WIMP idea still have something to look forward to as technology advances. LUX uses a third of a ton of liquid xenon. In 10 or 15 years, scientists are planning to build detectors that might contain 100 tons, providing even more chances of capturing that rare WIMP interaction. These are heady times to be a dark-matter scientist.-"But, in the end, we still don't know. We just know that the capabilities of LUX are good enough that maybe it's time to broaden our thinking. In the words of the rock band Buffalo Springfield, "There's something happening here. What it is ain't exactly clear...'"-Comment: The universe will one day reveal much more of its mysteries. Humans have the intelligence to do that. It is highly significant that life appeared quickly and resulted in organisms that can explore and interpret their own universe.

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The universe has generally a uniform pattern, but that pattern includes giant voids:

https://www.newscientist.com/article/2109398-space-is-full-of-gigantic-holes-that-are-b...

"Since 1981, when astronomers found a vacant expanse called the Boötes void, we’ve also known that the universe has holes of cold, dark, lonely nothing that are larger than anyone expected. To truly understand the universe, we may have to gaze into the abyss.

"The Boötes void, which you will assuredly not see if you look at Boötes, the “ploughman” constellation adjacent to the Big Dipper, is a rough sphere about 280 million light years in diameter.

"Galaxy-wise, it’s a ghost town. When we first saw the void, we found only one galaxy inside. Since then, we’ve detected only a few dozen more. By contrast, the Virgo Supercluster, a smaller region that includes the Milky Way, contains over 2000 galaxies.

"As residents of the Milky Way, humans are able to see one large nearby galaxy, Andromeda, with our naked eyes. The proximity of Andromeda helped Edwin Hubble look at its individual stars to unlock the true scope of the universe. If our galaxy were in the Boötes void, our nearest peers would be much farther away – perhaps allowing us to fancy ourselves at the center of the cosmos for longer.

"This is no statistical accident. At very large scales, the universe is often described as a cosmic web, with strands of invisible dark matter undergirding the universe’s luminous structure. It might be better here to think of it as cosmic foam, like soap bubbles in a bathtub. Just as it’s sudsy where bubbles intersect, galaxy clusters concentrate in walls, filaments and intersections. In between is mostly void. (my bold)

"The problem was that the Boötes void was just too big. Voids grow because their dense edges have a much stronger gravitational pull than anything at their centres. But the universe wasn’t yet old enough to have inflated such a big bubble.

"For an explanation, we had to wait until the 1998 discovery of dark energy: a cosmic pressure that forces empty regions of space to expand as if someone was blowing air into each of the universe’s soap bubbles all at once.

"Many astronomers, now in a boom of cataloging and mapping voids, think these spooky regions that expose the naked fabric of the universe could point to the next big discovery.

"Soon, statistical analyses of their shapes may be able to help us measure dark energy, gravity and any mysterious new forces better than ever before. And in the process, perhaps, they will help us learn to embrace the emptiness."

Comment: Is dark energy stronger in some areas than others, causing expansion of these voids. We still have lots to learn

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A new study questions that the expansion of the universe is increasing in speed:

http://phys.org/news/2016-10-universe-rateor.html

"..a team of scientists led by Professor Subir Sarkar of Oxford University's Department of Physics has cast doubt on this standard cosmological concept. Making use of a vastly increased data set - a catalogue of 740 Type Ia supernovae, more than ten times the original sample size - the researchers have found that the evidence for acceleration may be flimsier than previously thought, with the data being consistent with a constant rate of expansion.

"Professor Sarkar, who also holds a position at the Niels Bohr Institute in Copenhagen, said: 'The discovery of the accelerating expansion of the universe won the Nobel Prize, the Gruber Cosmology Prize, and the Breakthrough Prize in Fundamental Physics. It led to the widespread acceptance of the idea that the universe is dominated by "dark energy" that behaves like a cosmological constant - this is now the "standard model" of cosmology.

***

"However, there now exists a much bigger database of supernovae on which to perform rigorous and detailed statistical analyses. We analysed the latest catalogue of 740 Type Ia supernovae - over ten times bigger than the original samples on which the discovery claim was based - and found that the evidence for accelerated expansion is, at most, what physicists call "3 sigma". This is far short of the "5 sigma" standard required to claim a discovery of fundamental significance.

***

"There is other data available that appears to support the idea of an accelerating universe, such as information on the cosmic microwave background - the faint afterglow of the Big Bang - from the Planck satellite. However, Professor Sarkar said: 'All of these tests are indirect, carried out in the framework of an assumed model, and the cosmic microwave background is not directly affected by dark energy. Actually, there is indeed a subtle effect, the late-integrated Sachs-Wolfe effect, but this has not been convincingly detected.

"'So it is quite possible that we are being misled and that the apparent manifestation of dark energy is a consequence of analysing the data in an oversimplified theoretical model - one that was in fact constructed in the 1930s, long before there was any real data. A more sophisticated theoretical framework accounting for the observation that the universe is not exactly homogeneous and that its matter content may not behave as an ideal gas - two key assumptions of standard cosmology - may well be able to account for all observations without requiring dark energy. Indeed, vacuum energy is something of which we have absolutely no understanding in fundamental theory.'"

Comment: Scientific conclusions are never firmly established until every aspect is thoroughly studied. Consensus science should never be trusted. The universe is expanding, thus the Big Bang theory, but now the speed is questioned.

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David’s comment: Scientific conclusions are never firmly established until every aspect is thoroughly studied. Consensus science should never be trusted. The universe is expanding, thus the Big Bang theory, but now the speed is questioned.

Agreed. And by the same token we should not take the Big Bang theory itself as Big Bang fact, and we should certainly not take as fact the claim that the universe had a beginning which sprang from nothing.

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David’s comment: Scientific conclusions are never firmly established until every aspect is thoroughly studied. Consensus science should never be trusted. The universe is expanding, thus the Big Bang theory, but now the speed is questioned.

dhw: Agreed. And by the same token we should not take the Big Bang theory itself as Big Bang fact, and we should certainly not take as fact the claim that the universe had a beginning which sprang from nothing.

Something must come from something, That is absolutely clear. I just read that Einstein was a firm believe in cause and effect.

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This article strongly disagrees:

https://blogs.scientificamerican.com/guest-blog/no-astronomers-haven-t-decided-dark-ene...

"Once you read the article, however, it’s safe to say there is no need to revise our present understanding of the universe. All the paper does is slightly reduce our certainty in what we know—and then only by discarding most of the cosmological data on which our understanding is based. It also ignores important details in the data it does consider. And even if you leave aside these issues, the headlines are wrong anyway. The study concluded that we’re now only 99.7 percent sure that the universe is accelerating, which is hardly the same as “it’s not accelerating.”

***

"The recent paper that has generated headlines used a catalog of Type Ia supernovae collected by the community (including us) which has been analyzed numerous times before. But the authors used a different method of implementing the corrections—and we believe this undercuts the accuracy of their results. They assume that the mean properties of supernovae from each of the samples used to measure the expansion history are the same, even though they have been shown to be different and past analyses have accounted for these differences. However, even ignoring these differences, the authors still find that there is roughly a 99.7 percent chance that the universe is accelerating—very different from what the headlines suggest.

***

"Furthermore, the overwhelming confidence astronomers have that the universe is expanding faster now than it was billions of years ago is based on much more than just supernova measurements. These include tiny fluctuations in the pattern of relic heat after the Big Bang (i.e., the cosmic microwave background) and the modern day imprint of those fluctuations in the distribution of galaxies around us (called baryon acoustic oscillations). The present study also ignores the presence of a substantial amount of matter in the Universe, confirmed numerous times and ways since the 1970’s, further reducing the study confidence. These other data show the universe to be accelerating independently from supernovae. If we combine the other observations with the supernova data, we go from 99.99 percent sure to 99.99999 percent sure. That’s pretty sure!

"We now know that dark energy, which is what we believe causes the expansion of the universe to accelerate, makes up 70 percent of the universe, with matter constituting the rest. The nature of dark energy is still one of the largest mysteries of all of astrophysics. But there has been no active debate about whether dark energy exists and none about whether the universe is accelerating since this picture was cemented a decade ago.

"There are now many new large surveys, both on the ground and in space, whose top priority over the next two decades is to figure out exactly what this dark energy could be. For now, we have to continue to improve our measurements and question our assumptions. While this recent paper does not disprove any theories, it is still good for everyone to pause for a second and remember how big the questions are that we are asking, how we reached the conclusions we have to date and how seriously we need to test each building block of our understanding."

Comment: Over-hyped science reporting has served to confuse the issue. It seems that we are really expanding faster than thought in years past.

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A newer theory about how the Earth and Moon formed after a giant body struck the Earth:

http://phys.org/news/2016-10-theory-moon.html

"Earth's Moon is an unusual object in our solar system, and now there's a new theory to explain how it got where it is, which puts some twists on the current "giant impact" theory.

"The Moon is relatively big compared to the planet it orbits, and it's made of almost the same stuff, minus some more volatile compounds that evaporated long ago. That makes it distinct from every other major object in the Solar System, said Sarah Stewart, professor of earth and planetary sciences

"The Moon is relatively big compared to the planet it orbits, and it's made of almost the same stuff, minus some more volatile compounds that evaporated long ago. That makes it distinct from every other major object in the Solar System, said Sarah Stewart, professor of earth and planetary sciences at the University of California, Davis and senior author on the paper.

"'Every other body in the solar system has different chemistry," she said.
The textbook theory of lunar formation goes like this. Late in the formation of the solar system came the "giant impact" phase, when hot planet-size objects collided with each other. A Mars-sized object grazed what would become Earth, throwing off a mass of material from which the Moon condensed. This impact set the angular momentum for the Earth-Moon system, and gave the early Earth a five-hour day. Over millennia, the Moon has receded from the Earth and the rotation has slowed to our current 24-hour day.

***

"But there are a couple of problems with the textbook theory. One is the Moon's surprisingly Earth-like composition. Another is that if the Moon condensed from a disk of material rotating around Earth's equator, it should be in orbit over the equator. But the Moon's current orbit is tilted five degrees off the equator, meaning some more energy must have been put in to move it.

"In the new model, a high energy collision left a mass of vaporized and molten material from which the Earth and Moon formed. The Earth was set spinning with a two-hour day, its axis pointing towards the Sun.

"Over a few tens of million years, the Moon continued to slowly move away from Earth until it reached a second transition point, the Cassini transition, at which point the inclination of the Moon—the angle between the Moon's orbit and Earth's equator—dropped to about five degrees, putting the Moon more or less in its current orbit.

"The new theory elegantly explains the Moon's orbit and composition based on a single, giant impact at the beginning, Stewart said. No extra intervening steps are required to nudge things along.

"'One giant impact sets off the sequence of events," she said.

"Because the collision could have been more energetic than in the current theory, the material from Earth and the impactor would have mixed together, and both Earth and Moon condensed from the same material and therefore have a similar composition.

"As angular momentum was dissipated through tidal forces, the Moon receded from the Earth until it reached a point called the "LaPlace plane transition," where the forces from the Earth on the Moon became less important than gravitational forces from the Sun. This caused some of the angular momentum of the Earth-Moon system to transfer to the Earth-Sun system.

"This made no major difference to the Earth's orbit around the Sun, but it did flip Earth upright. At this point, the models built by the team show the Moon orbiting Earth at a high angle, or inclination, to the equator."

Comment: Note that Earth and Moon have a special relationship, not seen in the rest of the solar system, another part of all of the unusual characteristics of the Earth which makes it so special as it hosts life.

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Samples from the moon shows it appeared only 50-100 million years after the Earth:

https://cosmosmagazine.com/geoscience/apollo-14-gems-reveal-moon-s-age-4-51-billion-yea...

Melanie Barboni from the University of California, Los Angeles and colleagues analysed the chemistry of eight zircon grains in rock and soil, picked up during the 1971 moon mission, and found they suggest the moon was mostly solidified around 4.51 billion years ago.

With the odd exception, planetary scientists think the moon was produced when the early Earth collided with another protoplanet, dubbed Theia, in the first couple of hundred million years of the solar system.

The giant plume of material blasted off by the impact settled into a hot disc around Earth, which eventually clumped together to become the moon.

Back then, the moon (and Earth) were both hot balls of melted rock. But nailing down exactly when the moon solidified from the so-called lunar magma ocean has been tricky.

One way has been to date the products of the lunar magma ocean such as crystals that took shape as the hot rock cooled and hardened.

Was the Moon born in a head-on collision?

(It's not just a moon phenomenon either – zircons have been used to find the Earth's magnetic field 4.2 billion years ago.)

Lunar zircons are thought to form in the lunar magma ocean's potassium, rare-Earth elements and phosphorus (KREEP) reservoir. And because this reservoir formed towards the end of the magma ocean's hardening, they provide handy objects to determine when solidification took place.

Using a technique called isotope dilution thermal ionisation mass spectrometry – an incredibly sensitive technique that can accurately measure minute amounts of elements such as lead and uranium – Barboni and her crew found the zircon fragments crystallised between 50 and 60 million years after the birth of the solar system.

"Our data unambiguously show that the moon was [...] mostly solidified by 4.51 [billion years ago]," they write, with an uncertainty of around 10 million years.

Comment: The Earth Moon arrangement is most unusual, just one moon fairly sizeable which affects the Earth's tilt, the tides, and so close, they are tidally locked so we only see one side of he Moon which rotates only once per orbit.

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About ten times he amount previously estimated:

https://phys.org/news/2017-01-universe-trillion-galaxies.html

"An international team of astronomers, led by Christopher Conselice, Professor of Astrophysics at the University of Nottingham, have found that the universe contains at least 2 trillion galaxies, ten times more than previously thought.

"Astronomers have long sought to determine how many galaxies there are in the observable universe, the part of the cosmos where light from distant objects has had time to reach us. Over the last 20 years scientists have used images from the Hubble Space Telescope to estimate that the universe we can see contains around 100 - 200 billion galaxies. Current astronomical technology allows us to study just 10% of these galaxies, and the remaining 90% will be only seen once bigger and better telescopes are developed.

"Prof Conselice's research is the culmination of 15 years' work, part-funded by a research grant from the Royal Astronomical Society awarded to Aaron Wilkinson, an undergraduate student at the time. Aaron, now a PhD student at the University of Nottingham, began by performing the initial galaxy-counting analysis, work which was crucial for establishing the feasibility of the larger-scale study.

***

"The results of this study are based on the measurements of the number of observed galaxies at different epochs – different instances in time - through the universe's history. When Prof Conselice and his team at Nottingham, in collaboration with scientists from the Leiden Observatory at Leiden University in the Netherlands and the Institute for Astronomy at the University of Edinburgh, examined how many galaxies there were at a given epoch they found that there were significantly more at earlier times.

"It appears that when the universe was only a few billion years old there were ten times as many galaxies in a given volume of space as there are within a similar volume today. Most of these galaxies were low mass systems with masses similar to those of the satellite galaxies surrounding the Milky Way.

"Prof Conselice said: "This is very surprising as we know that, over the 13.7 billion years of cosmic evolution since the Big Bang, galaxies have been growing through star formation and mergers with other galaxies. Finding more galaxies in the past implies that significant evolution must have occurred to reduce their number through extensive merging of systems.'"

Comment: And we wonder, are we the only galaxy with life.

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Joseph Silk explains why it should exist, but no experiment has found any trace as yet. Perhaps we need new ideas?

http://cosmos.nautil.us/feature/133/will-we-ever-know-what-dark-matter-is?utm_source=Na...

Dark matter is as tangible as stars and planets to most astronomers. We routinely map it out. We conceive of galaxies as lumps of dark matter with dabs of luminous material. We understand the formation of cosmic structure, as well as the evolution of the universe as a whole, in terms of dark matter. Yet a decade of sophisticated searches has failed to detect the material directly. We see the shadow it casts, but are completely unaware of what the dark side of the universe may contain.

It certainly isn’t any ordinary object or particle—that has long since been ruled out. Theoretical prejudice favors a novel type of particle that interacts only weakly with ordinary matter. Vast numbers of these particles should be flowing through our planet all the time, and by rights you’d expect some of them to leave a mark. Physicists have grown crystals and filled cryogenic vats, hauled them deep underground to screen out run-of-the-mill particles, and watched for tiny pulses of heat and flashes of light that would betray the passage of something never before seen. The results so far are not encouraging. In Lead, South Dakota, the LUX experiment operates one mile underground in an abandoned gold mine. It has found nothing. In China, the PandaX experiment in the Jin-Ping underground laboratory operates in a tunnel under 2.4 kilometers of rock. It has found nothing. In a road tunnel near Fréjus in the French Alps, the EDELWEISS experiment, at a depth of 1.7 km, has found nothing. And the list goes on.

The null results are rapidly squeezing the regions of parameter space where dark matter might lurk. Confronted by the drought of data, theoretical physicists have conjectured about more exotic particles, but the vast majority of these candidates would be even harder to detect. One could instead hope to produce dark-matter particles at a particle accelerator, so that we could infer their presence by default: by checking whether energy seemed to go missing in particle collisions. But the Large Hadron Collider has tried precisely this and noticed nothing so far. Some theorists suspect dark matter doesn’t exist and our theory of gravitation—Einstein’s general theory of relativity—has led us astray. General relativity tells us that galaxies would fly apart if not held together by unseen matter, but perhaps the theory is wrong. Yet general relativity has passed all other observational tests, and all rival theories have seemingly fatal flaws.

Eighty-five percent of all matter is unknown. Our greatest fear is that it will always remain so.

***

In a sense, we are in the situation every scientist dreams of. Old ideas aren’t working; new ones are needed. These might come from exploring novel types of particles, or we might discover a fully consistent new theory of gravity that dispenses entirely with dark matter.

The nagging worry is that nature has put the new physics in a place where we can’t find it. Although we haven’t completely exhausted the search for WIMPs, there’s only so much more that experiments can do. As they become more sensitive to dark matter, they also become more sensitive to garbage particles, and they cannot always discriminate between the two. At the present rate of improvement, within a decade they will be blinded by neutrinos emitted either by the sun or by cosmic rays colliding with Earth’s atmosphere.

The strongest tool for discovery of dark-matter particles would be a new particle collider. Fast-forwarding some three decades from now, physicists plan to build a collider with seven times the power of the LHC. Studies are underway both in China and in Europe. Crudely scaling up from the LHC, it would cost $25 billion in today’s dollars. Shared among nations and spread over the decades, that might just be feasible. But it is probably the limit. Even if physicists had unlimited resources, nothing would be gained by building anything larger. At that point, any unknown particle would have to be so massive that, were the particle produced in the same way as its lighter counterparts, the big bang would not have produced it in sufficient quantity.

***

Despite these immense efforts, we may not find any signals. That would be a gloomy prospect. Maybe there is no dark matter. We keep looking for deviations from general relativity. So far we have found none. On the contrary, the detection of black holes in 2016 by gravitational waves has bolstered Einstein’s theory—and its corollary, the existence of dark matter.

But look on the bright side. There could be immense mysteries and revelations about the dark side of nature that we will never glimpse unless we search. For now, we keep looking for particles. We can do nothing else but press on.

Comment: Frustrating as the Standard Model works so well and Wimps should fit. We are accustomed to rapid science advances, but the easy stuff has been detected. God has not made it easy.

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70% of stars in the Milky Way spin the same way:

https://cosmosmagazine.com/space/astronomers-spin-the-story?utm_source=Today+in+Cosmos+...

Astronomers analysing ancient “starquakes” have discovered that most of the stars in the Milky Way have identical spins, contrary to expectations.

A team led by Enrico Corsaro from the Université Paris Diderot, in France, used asteroseismology to work out the spin-orientation of 48 stars in the Milky Way, to test the theory that turbulence during the galaxy’s formation would have resulted in wide variation.

To their surprise, the scientists discovered that 70% of the stars measured were aligned with one another.

“Just as seismologists use earthquakes to understand the interior of our planet, we use starquakes to understand the interior of stars,” says team member Dennis Stello from the University of New South Wales.

“Our new study provides the first evidence that this approach is a powerful way to gain insights into processes that occurred billions of years ago, close to the beginning of the universe.”

Comment: All we know is our galaxy stars are organized. We don't know if it only our Milky Way or all galaxies. We could be special and others vary. No way to find out.

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Early formed galaxies 10 billion years ago don't act like dark matter was present:

https://www.newscientist.com/article/2124793-dark-matter-took-its-time-to-wrap-around-e...

" About 10 billion years ago, massive star-forming galaxies were dominated by normal matter, not the dark matter that’s so influential in galaxies today.

***

"This study constituted some of the first evidence for dark matter, matter that doesn’t interact with light and which we can only observe via its gravitational effects. If a galactic disc sat in a pervasive dark matter “halo”, that extra unseen mass could explain the stars’ unexpected motion.

"In order to figure out how today’s galaxies came to be so full of dark matter, we have to look to their predecessors, the star-forming galaxies of the early universe. But learning about dark matter in galaxies in the early universe is difficult: because we cannot see dark matter, we must carefully observe the movements of extraordinarily distant stars.

"Now, Natascha Förster Schreiber at the Max Planck Institute for Extraterrestrial Physics in Germany and her colleagues have used the Very Large Telescope in Chile to make the most detailed observations yet of the movement of six massive galactic discs during the peak era of galaxy formation, 10 billion years ago.

"They found that, unlike in most modern galaxies, the stars at the edges of these early galaxies move more slowly than those closer in. “This tells us that at early stages of galaxy formation, the relative distribution of the normal matter and the dark matter was significantly different from what it is today,” says Förster Schreiber.

"In order to check their unexpected results, the researchers used a “stack” of 100 images of other early galaxies to find an average picture of their rotations. The stacked galaxies matched the rotations of the more rigorously studied ones. “We’re not just looking at six weirdo galaxies – this could be more common,” says Förster Schreiber. “For me, that was the wow moment.”

"The differences in early galaxies’ rotations demonstrates that there is very little dark matter in towards their middle. Instead, they are almost entirely made up of the matter we can see in the form of stars and gas. The further away (and thus earlier in cosmic history) the galaxies were, the less dark matter they contained.

"This result suggests that the turbulent gas in early galaxies condensed into the flat, rotating disc shapes we see today more quickly than dark matter, which remained in a diffuse halo around galaxies for longer.

“'This is an important step in trying to figure out how galaxies like the Milky Way and larger galaxies must have assembled,” says Mark Swinbank at Durham University. “Having a constraint on how early the gas and stars must have formed the discs and how well-mixed they were with dark matter is important to informing their evolution.'”

Comment: this finding that dark matter evolved as the universe evolved suggests that not all galaxies can be compared as the same. The comment I made about coordinated spinning stars earlier today in the previous entry is supported by this study that perhaps galaxies can be very different depending on age. This is more evidence that the universe evolved and God uses an evolutionary method to achieve His goals.

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We may be in an area of dark energy that is different from other regions of the universe, or not:

http://nautil.us/issue/46/balance/can-dark-energy-kill-galaxies?utm_source=Nautilus&...

"We’re not sure what is causing the expansion to accelerate, so we’ve called it “dark energy.” Our best theories of what matter is and does give us a candidate for what dark energy might be—something called vacuum energy. It’s the energy in a region of space, contained in the electromagnetic field and its cousins, even when there are no particles. But when physicists attempted to calculate the amount of vacuum energy, they got a shock. The answer was about 10^120 times larger than the actual value learned from observation. This is a problem.

"Steven Weinberg, the Nobel Prize-winning physicist, had wrestled with the theoretical overestimate and suggested a remarkable solution. He noted that the amount of vacuum energy can vary from place to place, depending on how all the different fields in the universe add and subtract. In our region of space, the amount of vacuum energy is minuscule, requiring all these fields to cancel one another out to an incredible degree. That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere. In the vast majority of cosmic regions, the excess of dark energy throws off the balance of forces that enables galaxies, stars, planets, and people to form. We see an improbably precise cancellation of known and unknown fields because we couldn’t exist otherwise.

"Our cosmic environment is the result of a delicate balance of cosmic forces—gravity and pressure, cooling and heating, expansion and collapse. The final product, when all these pushes and pulls come into balance, is our Milky Way galaxy, where stars form in a rotating disk of gas and a diffuse halo of dark matter.

***

"With this physics, and weeks to months on thousands of linked computers, these simulations reveal a condensing web of cosmic structure, with dark matter and ordinary matter coming together to produce remarkably realistic galaxies. If Weinberg is right, this process should not work in regions of the universe that have more dark energy.

***

"If we continue to ramp up the dark energy, the formation of structure freezes before even the smallest galaxies form. None of the matter in the universe manages to form into galaxies, stars, planets, or people. The entire universe is stillborn—a diffuse, expanding gas of particles that very occasionally bounce off each other, but do little else. There is no life, because there is no structure or complexity at all.

***

"In our universe, star formation was most efficient a few billion years before dark energy started driving accelerating expansion. By the time galaxies were isolated by cosmic acceleration, star production was declining anyway. Stellar feedback is the major reason why the universe doesn’t form stars very efficiently. Dark energy is only a secondary villain.

***

"Suppose there are other regions of the universe with more or less dark energy than we have. Essentially, each region picks a number between zero and 10^120, on a scale where our own region picked 1. Now imagine taking your survey clipboard around to check on the lifeforms that evolved in those regions; if you meet one, ask how much dark energy they see. Most regions are dead, of course, which explains why there is no one to tell you, “My region picked 10^30 or 10^90.” But there are plenty of observers who see 10 or 100 or more, in which case we might wonder why we are the outliers who see a value of 1. If the theory says “expect about 100,” but we see 1, we cannot explain our value as a mere selection effect."

Comment: Barnes is suggesting we live in a special place in the universe which supports our very special Milky Way. Is this God at work to protect life in a vast universe? Makes sense to me. Read the entire article to follow his reasoning.

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DAVID: We may be in an area of dark energy that is different from other regions of the universe, or not:
http://nautil.us/issue/46/balance/can-dark-energy-kill-galaxies?utm_source=Nautilus&...

DAVID’s comment: Barnes is suggesting we live in a special place in the universe which supports our very special Milky Way. Is this God at work to protect life in a vast universe? Makes sense to me. Read the entire article to follow his reasoning.

Since we do not know the extent of the universe, and there may even be an infinite number of “regions”, we have no idea how many regions are similar to/different from our own, but as ours is the only one we know that supports life, it’s fair enough to say it’s special. Tucked away in this article, however, is a significant comment to counterbalance your own:

QUOTE: “In our region of space, the amount of vacuum energy is minuscule, requiring all these fields to cancel one another out to an incredible degree. That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere.”

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DAVID: We may be in an area of dark energy that is different from other regions of the universe, or not:
http://nautil.us/issue/46/balance/can-dark-energy-kill-galaxies?utm_source=Nautilus&...

DAVID’s comment: Barnes is suggesting we live in a special place in the universe which supports our very special Milky Way. Is this God at work to protect life in a vast universe? Makes sense to me. Read the entire article to follow his reasoning.

dhw: Since we do not know the extent of the universe, and there may even be an infinite number of “regions”, we have no idea how many regions are similar to/different from our own, but as ours is the only one we know that supports life, it’s fair enough to say it’s special. Tucked away in this article, however, is a significant comment to counterbalance your own:

QUOTE: “In our region of space, the amount of vacuum energy is minuscule, requiring all these fields to cancel one another out to an incredible degree. That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere.”

The quote can be easily interpreted as supporting my comment: life is extremely improbable and our region has it! But look at the full context of the whole quote:

"That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere. In the vast majority of cosmic regions, the excess of dark energy throws off the balance of forces that enables galaxies, stars, planets, and people to form. We see an improbably precise cancellation of known and unknown fields because we couldn’t exist otherwise." (my bold) Please avoid cherry picking. I'm watching.

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DAVID: We may be in an area of dark energy that is different from other regions of the universe, or not:
http://nautil.us/issue/46/balance/can-dark-energy-kill-galaxies?utm_source=Nautilus&...

DAVID’s comment: Barnes is suggesting we live in a special place in the universe which supports our very special Milky Way. Is this God at work to protect life in a vast universe? Makes sense to me. Read the entire article to follow his reasoning.

dhw: “Since we do not know the extent of the universe, and there may even be an infinite number of “regions”, we have no idea how many regions are similar to/different from our own, but as ours is the only one we know that supports life, it’s fair enough to say it’s special.”Tucked away in this article, however, is a significant comment to counterbalance your own: (Dhw's bold, see below)

QUOTE: “In our region of space, the amount of vacuum energy is minuscule, requiring all these fields to cancel one another out to an incredible degree. That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere.”

DAVID: The quote can be easily interpreted as supporting my comment: life is extremely improbable and our region has it! But look at the full context of the whole quote:

"That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere. In the vast majority of cosmic regions, the excess of dark energy throws off the balance of forces that enables galaxies, stars, planets, and people to form. We see an improbably precise cancellation of known and unknown fields because we couldn’t exist otherwise." (David's bold) Please avoid cherry picking. I'm watching.

Firstly, I offered his quote as a “counterbalance” to your comment, not as a refutation. Secondly, the passage I quoted stressed the improbability and indeed the incredibility. Thirdly, I did not dispute the fact that we could not exist otherwise, and indeed I actually stated that we were special. I have put that in bold.

No cherry-picking but, quoting the same facts, I have simply pointed out that Barnes has offered a different explanation from yours. I know you are watching me. Please watch more carefully! ;-)

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QUOTE: “In our region of space, the amount of vacuum energy is minuscule, requiring all these fields to cancel one another out to an incredible degree. That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere.”

DAVID: The quote can be easily interpreted as supporting my comment: life is extremely improbable and our region has it! But look at the full context of the whole quote:

"That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere. In the vast majority of cosmic regions, the excess of dark energy throws off the balance of forces that enables galaxies, stars, planets, and people to form. We see an improbably precise cancellation of known and unknown fields because we couldn’t exist otherwise." (David's bold) Please avoid cherry picking. I'm watching.

dhw: Firstly, I offered his quote as a “counterbalance” to your comment, not as a refutation. Secondly, the passage I quoted stressed the improbability and indeed the incredibility. Thirdly, I did not dispute the fact that we could not exist otherwise, and indeed I actually stated that we were special. I have put that in bold.

No cherry-picking but, quoting the same facts, I have simply pointed out that Barnes has offered a different explanation from yours. I know you are watching me. Please watch more carefully!

I don't see how Barnes and I differ. My only point from his text was our area of the universe is special and we are here.

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Dhw: No cherry-picking but, quoting the same facts, I have simply pointed out that Barnes has offered a different explanation from yours. I know you are watching me. Please watch more carefully! ;-)

DAVID: I don't see how Barnes and I differ. My only point from his text was our area of the universe is special and we are here.

Your comment was: Barnes is suggesting we live in a special place in the universe which supports our very special Milky Way. Is this God at work to protect life in a vast universe? Makes sense to me.

Barnes’s comment was: “In our region of space, the amount of vacuum energy is minuscule, requiring all these fields to cancel one another out to an incredible degree. That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere.”

You suggest that the incredible specialness suggests God at work, and he suggests that the vastness allows for even the most improbable event. The classic clash between God and chance.

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Dhw: No cherry-picking but, quoting the same facts, I have simply pointed out that Barnes has offered a different explanation from yours. I know you are watching me. Please watch more carefully!

DAVID: I don't see how Barnes and I differ. My only point from his text was our area of the universe is special and we are here.

dhw: Your comment was: Barnes is suggesting we live in a special place in the universe which supports our very special Milky Way. Is this God at work to protect life in a vast universe? Makes sense to me.

Barnes’s comment was: “In our region of space, the amount of vacuum energy is minuscule, requiring all these fields to cancel one another out to an incredible degree. That seems highly improbable, but in any large enough system, even the most improbable event will occur somewhere.”

You suggest that the incredible specialness suggests God at work, and he suggests that the vastness allows for even the most improbable event. The classic clash between God and chance.

I would emphasize from Barnes' comment: 'in our region of space' is where we exist. Barnes is religious and must make the comment allowing for chance as a balanced statement of possibility. Perhaps God's vastness in the universe allows for that chance arrangement in our area, most likely under God's guidance.

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DAVID: I don't see how Barnes and I differ. My only point from his text was our area of the universe is special and we are here.

Dhw: You suggest that the incredible specialness suggests God at work, and he suggests that the vastness allows for even the most improbable event. The classic clash between God and chance.

DAVID: I would emphasize from Barnes' comment: 'in our region of space' is where we exist. Barnes is religious and must make the comment allowing for chance as a balanced statement of possibility. Perhaps God's vastness in the universe allows for that chance arrangement in our area, most likely under God's guidance.

“Under God’s guidance” would hardly constitute chance. The “balanced statement of possibility” was what I was pointing out - just to balance your own comment.

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This is another special aspect of our galaxy. living in a giant void in the Swiss cheese of a universe:

https://phys.org/news/2017-06-celestial-boondocks-idea-void.html

"Cosmologically speaking, the Milky Way and its immediate neighborhood are in the boondocks

"In a 2013 observational study, University of Wisconsin-Madison astronomer Amy Barger and her then-student Ryan Keenan showed that our galaxy, in the context of the large-scale structure of the universe, resides in an enormous void—a region of space containing far fewer galaxies, stars and planets than expected.

"Now, a new study by a UW-Madison undergraduate, also a student of Barger's, not only firms up the idea that we exist in one of the holes of the Swiss cheese structure of the cosmos, but helps ease the apparent disagreement or tension between different measurements of the Hubble Constant, the unit cosmologists use to describe the rate at which the universe is expanding today.

***

"The new Wisconsin report is part of the much bigger effort to better understand the large-scale structure of the universe. The structure of the cosmos is Swiss cheese-like in the sense that it is composed of "normal matter" in the form of voids and filaments. The filaments are made up of superclusters and clusters of galaxies, which in turn are composed of stars, gas, dust and planets. Dark matter and dark energy, which cannot yet be directly observed, are believed to comprise approximately 95 percent of the contents of the universe.

"The void that contains the Milky Way, known as the KBC void for Keenan, Barger and the University of Hawaii's Lennox Cowie, is at least seven times as large as the average, with a radius measuring roughly 1 billion light years. To date, it is the largest void known to science. Hoscheit's new analysis, according to Barger, shows that Keenan's first estimations of the KBC void, which is shaped like a sphere with a shell of increasing thickness made up of galaxies, stars and other matter, are not ruled out by other observational constraints."

Comment: Our galaxy has life. We don't want lots of dangerous stuff exploding round us and we don't want to run into another galaxy for some time. This void is protective. Currently we are scheduled to run into Andromeda in about two billion years. That alone could be destructible enough to destroy life before our sun expands and finishes Earth life five billion years from now. The time term for life in this arrangement is finite. Will that be the end of it or is there another solution God will present?

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Comment: Our galaxy has life. We don't want lots of dangerous stuff exploding round us and we don't want to run into another galaxy for some time. This void is protective. Currently we are scheduled to run into Andromeda in about two billion years. That alone could be destructible enough to destroy life before our sun expands and finishes Earth life five billion years from now. The time term for life in this arrangement is finite. Will that be the end of it or is there another solution God will present?

Thank goodness. Look at this report about clusters of galaxies colliding:

https://cosmosmagazine.com/space/space-hots-up-when-galaxy-clusters-collide

Astronomers from the University of Colorado at Boulder have been watching two enormous galaxy clusters that are merging to create an even bigger cluster dubbed Abell 115, some 2.4 billion light years away.

In an unexpected outcome, the collision between the two clusters has produced a turbulent region of hot gas, with temperatures reaching 1.7 million degrees Celsius. That’s approximately three times hotter than either of the cluster cores.

***

To estimate the temperature of Abell 115, Burns and his team developed software to create high contrast temperature maps of all the regions in the two colliding clusters, using the X-ray and radio portions of the electromagnetic spectrum.

The results were then fed through NASA’s Ames Research Centre supercomputer.
As well as the unexpected heat produced, the results also show that the newly forming super-cluster is sending radio emissions a long way out into deep space.

“These radio emissions are caused by electrons in the magnetic field of the galaxy cluster traveling at near the speed of light,” says Burns.

“Clearly something has energised the electrons, which we think is related to the cluster banging process.”

Each of the clusters contains hundreds of galaxies, many the size of the Milky Way. Their collision, says Burns, is one of the “biggest bangs in the universe since the Big Bang”.
The team predicts that eventually the turbulence created by the collision will abate and the new mega-cluster will reach some form of equilibrium.

“We believe Abell 115 will eventually ‘relax’ and become centrally condensed,” says Burns, “which is relatively boring compared to what we are seeing now.”

Comment: the universe is a dangerous place for life to exist. Thank goodness we are in a quiet spot. Purposefully?

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Einstein descried space as a space/time fabric. It acts gooier than that:

http://nautil.us/issue/49/the-absurd/what-is-space?utm_source=Nautilus&utm_campaign...

" Is space like an infinite void waiting to be filled? Or does it only exist in the context of matter?

"It turns out that we are fairly certain that space is neither of these things. Space is definitely not an empty void and it is definitely not just a relationship between matter. We know this because we have seen space do things that fit neither of those ideas. We have observed space bend and ripple and expand.

"If you are paying attention, you should be a little confused when you read the phrases “bending of space” and “expanding of space.” What could that possibly mean? How does it make any sense? If space is an idea, then it can’t be bent or expanded any more than it can be chopped into cubes and sautéed with cilantro. If space is our ruler for measuring the location of stuff, how do you measure the bending or expanding of space?

***

"To make sense of general relativity and think about modern ideas of space, you have to give up the idea of space as an abstract stage and accept that it is a physical thing. You have to imagine that space has properties and behaviors, and that it reacts to the matter in the universe. You can pinch space, squeeze it, and, yes, even fill it with cilantro.

"How can space be a physical thing that ripples and bends, and what does that mean?

"It means that instead of being like an empty room (a really big room) space is more like a huge blob of thick goo. Normally, things can move around in the goo without any problems, just like we can move around a room full of air without noticing all the air particles. But under certain circumstances, this goo can bend, changing the way that things move through it. It can also squish and make waves, changing the shape of the things inside it.

***

"And we know that space can expand because we have seen it expanding—this is how dark energy was discovered. We know that in the early universe space expanded and stretched at shocking rates, and that a similar expansion is still happening today.

***

" Light, for example, bends its path when it passes near massive objects like our sun or giant blobs of dark matter. If gravity was just a force between objects with mass—rather than the bending of space—then it shouldn’t be able to pull on photons, which have no mass. The only way to explain how light’s path can be bent is if it’s the space itself that is bending.

***

"Is it possible to have parts of the universe without space? In other words, if space is a goo, is it possible for there to be not-goo, or the absence of goo? The meaning of those concepts is not very clear because all of our physical laws assume the existence of space, so what laws could operate outside of space? We have no idea.

***

"If your brain is not yet hurting from all these gooey space-bending concepts, here is another mystery about space: Is space flat or curved (and if it’s curved, which way does it curve)?

***

"All the mass and energy in the universe is what gives space its curvature (remember that mass and energy distort space), and if we had just a little bit more mass and energy than we have right now, space would have curved one way. And if we had just a little bit less than we have right now, space would have curved the other way. But we seem to have just the right amount to make space perfectly flat as far as we can tell.

***

"Space can be flat and infinite. Or it could be flat and have an edge to it. Or, even stranger, it could be flat and still loop around itself."

Comment: Quantum space is also discussed. See the article. The cartoons are great.

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By working in a satellite Galileo's falling body experiment proven again:

http://bigthink.com/paul-ratner/doing-galileoexperiment-in-space-proved-einstein-right?...

"An experiment designed by the legendary Italian astronomer Galileo Galilei (1564 - 1642) was recreated in space and proved another famous scientist right, confirming a part of Einstein’s theory of gravity with unprecedented precision.

"The original experiment allegedly involved Galileo dropping two balls from the Leaning Tower of Pisa. Doing that proved that they fell at the same rate, regardless of what they were made of. While it’s still debated if Galileo actually carried out such an experiment, scientists performed a similar one in an Earth-orbiting satellite.

"Instead of balls, however, the researchers from the French-led MICROSCOPE satellite science team had two hollow cylinders free-falling inside a satellite for over 120 orbits or eight days worth of time. What they found is that accelerations exhibited by the cylinders matched to a two-trillionths of a percent. So pretty well.

"The results support the equivalence principle of Einstein’s general theory of relativity. It states that an object’s inertial mass, which determines the amount of force needed for acceleration, is equal to the gravitational mass - an indication of how the object is affected by the gravitational field. This idea proposes that things fall at the same rate in a vacuum (without air resistance), even if they are made of different stuff and have varying masses.

"To conduct the experiment, the scientists put a hollow cylinder made of platinum alloy into another hollow cylinder made of titanium alloy. The satellite used electrical forces to keep the two aligned as the objects fell in orbit around Earth. A difference in the amounts of applied forces would have potentially indicated a violation of the equivalence principle. No such differences were observed between them, achieving 10 times the precision of previous tests.

"The scientists hope to achieve precision that’s 100 times better than what others have been able to pull off. Why? Because even though the equivalence principle has held so far, there have been predictions that violations of the principle could be observed at some level that’s not been detected yet. Understanding if that’s true could hold the key to reconciling general relativity with quantum physics. "

Comment: General relativity works every time.

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These are theorized as being fine cracks in the universe and are thought, if they exist, to be pure energy:

https://cosmosmagazine.com/physics/cracks-in-the-universe

"Our universe exploded into being, expanded at a fantastic speed and cooled. Perhaps too quickly. Some physicists believe the rapid cooling might have cracked the fabric of the universe.

"These hairline fractures may still be threaded through space-time. Dubbed cosmic strings, mathematical models see them as invisible threads of pure energy, thinner than an atom but light-years long. The huge amount of energy they contain also makes them extremely heavy; a few centimetres of cosmic string might weigh as much as Mount Everest.

***

"However, as time capsules of the early universe, cosmic strings should retain fantastic energies – more than a billion times greater than those released by smashing particles at the Large Hadron Collider, says Ken Olum, a theoretical physicist at Tufts University in Boston, who has contemplated cosmic strings for 20 years. “You can’t build an accelerator to test physics at that scale.”

"Neither can any of our astronomical instruments detect these vanishingly thin, intergalactic filaments. For some physicists, a theory that can’t be tested is not worth pursuing. It places cosmic strings in the same category as “string theory”, their controversial namesake at the other extreme of the size scale......For Matthew Bailes, an astrophysicist at Swinburne University of Technology in Melbourne, cosmic strings are a “mathematical curiosity” or worse, “an exotic fantasy”.

"All that may be about to change. The nascent era of gravitational wave astronomy – just two years old – may finally deliver a tool to test the existence of cosmic strings. We can’t see them but gravitational wave detectors might be able to hear the thrums and snaps created as they whip through space.

***

"British field theorist Tom Kibble, who died in June 2016, came up with the idea of cosmic strings in 1976. He was musing about the first split second after the Big Bang when the universe underwent a rapid expansion, then cooled rapidly. This, he suggested, caused a phase change in the quantum fields, like water freezing to ice.

"In a block of ice, some regions can freeze with their crystals in different orientations, rather like tiles being laid simultaneously at different ends of a room. Where they meet, they don’t fit together smoothly, resulting in a crack. Likewise Kibble surmised that the quantum phase changes in the early universe would have caused the fields to align in different orientations, again causing cracks – cosmic strings.

***

'Vilenkin was thinking about this problem when he picked up on an aside in Kibble’s 1976 paper: when a cosmic string wriggling in the void crossed itself, it would chop off a self-contained ‘loop’. These loops would be light-year-sized hula-hoops in space – and enormously heavy. Vilenkin ran the numbers, and realised the number of cosmic loops that would have existed in the early universe was curiously close to the number of galaxies. Perhaps, he reasoned, a cosmic loop could seed a young galaxy, much like a grain of sand seeds a pearl.

***

"Cosmic strings can’t be seen but they might be heard. Gravitational waves are ripples in spacetime generated by massive objects moving extremely fast – like a pair of inspiralling black holes or neutron stars. Or a writhing cosmic string.

“'What happens is like a whip,” explains Damour, who worked out the idea with Vilenkin in 2000. The crack of a bullwhip is actually a sonic boom caused when part of its tail moves faster than the speed of sound.

***

"Even if the evidence continues to come up negative, some physicists are unlikely to let go of cosmic strings. Siemens says the strings might have been formed with too low an energy to give off any signals “detectable in the near future”. Another possibility is that ancient cosmic strings radiated away their energy and faded to nothingness too quickly after the Big Bang to have left a lasting impression.

"For now, cosmic strings sit on the shelf alongside other beautiful ideas that could complete our understanding of the universe, but lack empirical support. “This is the beauty and the danger of physics,” Damour says. “Sometimes things exist that we can never see.'”

Comment: Really far out, but the significance for me is that the theorists say that pure energy can exist. It is my theory about God that He is the First Cause, and He thinks and plans without any matter neurons and the universe is an extension of some of His energy, planned and formed by Him and evolved by Him.

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QUOTE: "These hairline fractures may still be threaded through space-time. Dubbed cosmic strings, mathematical models see them as invisible threads of pure energy, thinner than an atom but light-years long. The huge amount of energy they contain also makes them extremely heavy; a few centimetres of cosmic string might weigh as much as Mount Everest.

DAVID’s comment: Really far out, but the significance for me is that the theorists say that pure energy can exist. It is my theory about God that He is the First Cause, and He thinks and plans without any matter neurons and the universe is an extension of some of His energy, planned and formed by Him and evolved by Him.

Perhaps you can explain to me how the energy can be pure if the strands are thinner than a (material) atom and “CONTAIN” the energy. Is it then possible to have “pure” energy without a material container? And does energy have weight?

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QUOTE: "These hairline fractures may still be threaded through space-time. Dubbed cosmic strings, mathematical models see them as invisible threads of pure energy, thinner than an atom but light-years long. The huge amount of energy they contain also makes them extremely heavy; a few centimetres of cosmic string might weigh as much as Mount Everest.

DAVID’s comment: Really far out, but the significance for me is that the theorists say that pure energy can exist. It is my theory about God that He is the First Cause, and He thinks and plans without any matter neurons and the universe is an extension of some of His energy, planned and formed by Him and evolved by Him.

dhw: Perhaps you can explain to me how the energy can be pure if the strands are thinner than a (material) atom and “CONTAIN” the energy. Is it then possible to have “pure” energy without a material container? And does energy have weight?

You didn't read my excepts. The theorists note the strings are very heavy and are cracks in space time which gives them a container:

"These hairline fractures may still be threaded through space-time. Dubbed cosmic strings, mathematical models see them as invisible threads of pure energy, thinner than an atom but light-years long. The huge amount of energy they contain also makes them extremely heavy; a few centimetres of cosmic string might weigh as much as Mount Everest."

Perhaps you did read this and doubt their theoretical conclusions. All the while you believe a very few scientists who believe cells are intelligent, when the cells are most likely automatically following intelligent instructions in the information they contain to manage living.

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DAVID’s comment: Really far out, but the significance for me is that the theorists say that pure energy can exist. It is my theory about God that He is the First Cause, and He thinks and plans without any matter neurons and the universe is an extension of some of His energy, planned and formed by Him and evolved by Him.

dhw: Perhaps you can explain to me how the energy can be pure if the strands are thinner than a (material) atom and “CONTAIN” the energy. Is it then possible to have “pure” energy without a material container? And does energy have weight?

DAVID: You didn't read my excepts. The theorists note the strings are very heavy and are cracks in space time which gives them a container:
"These hairline fractures may still be threaded through space-time. Dubbed cosmic strings, mathematical models see them as invisible threads of pure energy, thinner than an atom but light-years long. The huge amount of energy they contain also makes them extremely heavy; a few centimetres of cosmic string might weigh as much as Mount Everest."
Perhaps you did read this and doubt their theoretical conclusions. All the while you believe a very few scientists who believe cells are intelligent, when the cells are most likely automatically following intelligent instructions in the information they contain to manage living.

My questions have absolutely nothing to do with cellular intelligence, and I am in no position even to discuss the researchers’ theoretical conclusions! I simply don’t understand how “pure” energy can have weight. And I don’t understand how a crack or “thread” can be thinner than an atom (i.e. materially measurable), "contain" all this energy, and yet not itself be part of the material universe. You haven’t answered either of my questions, so maybe you don’t understand either.

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DAVID’s comment: Really far out, but the significance for me is that the theorists say that pure energy can exist. It is my theory about God that He is the First Cause, and He thinks and plans without any matter neurons and the universe is an extension of some of His energy, planned and formed by Him and evolved by Him.

dhw: Perhaps you can explain to me how the energy can be pure if the strands are thinner than a (material) atom and “CONTAIN” the energy. Is it then possible to have “pure” energy without a material container? And does energy have weight?

DAVID: You didn't read my excepts. The theorists note the strings are very heavy and are cracks in space time which gives them a container:
"These hairline fractures may still be threaded through space-time. Dubbed cosmic strings, mathematical models see them as invisible threads of pure energy, thinner than an atom but light-years long. The huge amount of energy they contain also makes them extremely heavy; a few centimetres of cosmic string might weigh as much as Mount Everest."
Perhaps you did read this and doubt their theoretical conclusions. All the while you believe a very few scientists who believe cells are intelligent, when the cells are most likely automatically following intelligent instructions in the information they contain to manage living.

dhw: My questions have absolutely nothing to do with cellular intelligence, and I am in no position even to discuss the researchers’ theoretical conclusions! I simply don’t understand how “pure” energy can have weight. And I don’t understand how a crack or “thread” can be thinner than an atom (i.e. materially measurable), "contain" all this energy, and yet not itself be part of the material universe. You haven’t answered either of my questions, so maybe you don’t understand either.

The initial singularity which was the proposed start of the universe was pure energy and of enormous weight equal to that of the universe itself. That's the theorists point of view, that energy has weight! As for the cell theorists I'm simply pointing what is good for the goose is good for the gander. You sincerely believe some scientists when they fit your desired point of view, but then question others. As for thinness of the heavy cracks, that is in the space/time field which only has virtual particles, not atoms.

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DAVID: Perhaps you did read this and doubt their theoretical conclusions. All the while you believe a very few scientists who believe cells are intelligent, when the cells are most likely automatically following intelligent instructions in the information they contain to manage living.

dhw: My questions have absolutely nothing to do with cellular intelligence, and I am in no position even to discuss the researchers’ theoretical conclusions! I simply don’t understand how “pure” energy can have weight. And I don’t understand how a crack or “thread” can be thinner than an atom (i.e. materially measurable), "contain" all this energy, and yet not itself be part of the material universe. You haven’t answered either of my questions, so maybe you don’t understand either.

DAVID: The initial singularity which was the proposed start of the universe was pure energy and of enormous weight equal to that of the universe itself. That's the theorists point of view, that energy has weight!

I googled and found this, which seems to indicate that energy can only have weight when it turns into material. It’s a bit beyond me, but I’m sure you will understand it.

Does energy have weight ? The answer is ... no | Naked ...
https://www.thenakedscientists.com/forum/index.php?topic=71719.0

Does energy have weight? The answer is ... no
Does passive time have weight? The answer is no
But, when passive time merges with energy, material is created.
The material has weight. (DHW’S BOLD)
The weight of this material is its passive energy, which is distinguished with a simple spring.
Passive energy does not participate in the energy conservation law.
The passive energy of matter comes from its energy, which merges with passive time.
It is indeed a wondrous wonder. The material is created from two "abstract things" passive time and energy,

DAVID: As for the cell theorists I'm simply pointing what is good for the goose is good for the gander. You sincerely believe some scientists when they fit your desired point of view, but then question others.

Steady! I offer it as a hypothesis which makes sense to me, but I haven’t yet reached the point of “sincere belief”. It is you who “sincerely believe” those scientists who fit your desired point of view, which is a perfectly natural thing to do anyway!

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DAVID: The initial singularity which was the proposed start of the universe was pure energy and of enormous weight equal to that of the universe itself. That's the theorists point of view, that energy has weight!

dhw: I googled and found this, which seems to indicate that energy can only have weight when it turns into material. It’s a bit beyond me, but I’m sure you will understand it.

Does energy have weight ? The answer is ... no | Naked ...
https://www.thenakedscientists.com/forum/index.php?topic=71719.0

Does energy have weight? The answer is ... no
Does passive time have weight? The answer is no
But, when passive time merges with energy, material is created.
The material has weight. (DHW’S BOLD)
The weight of this material is its passive energy, which is distinguished with a simple spring.
Passive energy does not participate in the energy conservation law.
The passive energy of matter comes from its energy, which merges with passive time.
It is indeed a wondrous wonder. The material is created from two "abstract things" passive time and energy,

Did you read the comments below what you quoted???!!! Swallowing something in Google whole hog is not thinking. The comments are like my reaction, incorrect. A singularity is of tremendous weight and is pure energy. It depends upon the circumstances of what is being discussed. An Astronaut's weight on Earth is not his weight on the Moon.

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DAVID: The initial singularity which was the proposed start of the universe was pure energy and of enormous weight equal to that of the universe itself. That's the theorists point of view, that energy has weight!

dhw: I googled and found this, which seems to indicate that energy can only have weight when it turns into material. It’s a bit beyond me, but I’m sure you will understand it.

Does energy have weight ? The answer is ... no | Naked ...
https://www.thenakedscientists.com/forum/index.php?topic=71719.0

Does energy have weight? The answer is ... no
Does passive time have weight? The answer is no
But, when passive time merges with energy, material is created.
The material has weight. (DHW’S BOLD)
The weight of this material is its passive energy, which is distinguished with a simple spring.
Passive energy does not participate in the energy conservation law.
The passive energy of matter comes from its energy, which merges with passive time.
It is indeed a wondrous wonder. The material is created from two "abstract things" passive time and energy,

David: Did you read the comments below what you quoted???!!! Swallowing something in Google whole hog is not thinking. The comments are like my reaction, incorrect. A singularity is of tremendous weight and is pure energy. […]

The only relevant comment I could find was:
“I have never seen this energy you speak of, 2hat (sic) is it and how does one measure its mass”.

I have my doubts about the initial singularity, and must confess that I have never experienced or weighed a singularity or pure energy. You say this is what the theorists tell us, and the theorist I quoted says differently. I am in no position to argue about it. You state these theories as if they were facts, but I'm not happy to swallow them "whole hog" - I like to think about them. That is why I ask questions.

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David: Did you read the comments below what you quoted???!!! Swallowing something in Google whole hog is not thinking. The comments are like my reaction, incorrect. A singularity is of tremendous weight and is pure energy. […]

dhw: The only relevant comment I could find was:
“I have never seen this energy you speak of, 2hat (sic) is it and how does one measure its mass”.

I have my doubts about the initial singularity, and must confess that I have never experienced or weighed a singularity or pure energy. You say this is what the theorists tell us, and the theorist I quoted says differently. I am in no position to argue about it. You state these theories as if they were facts, but I'm not happy to swallow them "whole hog" - I like to think about them. That is why I ask questions.

It is certainly good to question what the so-called expert theorists tell us, but they sharply question each other. Remember the 'first' gravitational waves turned into dust. I present a distillation of the general conclusions.

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It simplifies our understanding of space:

https://www.agnosticweb.com/index.php?id=28167

Einstein’s theory represented a major simplification of the underlying math.

"His 1905 theory of special relativity showed that there’s a give-and-take to space and time, which together make up the bendy, warping “space-time” fabric. Thinking this way led him and others to a closer examination of the symmetries of the universe, or all the ways you can shift, rotate and move through it and still measure the same separation between objects or events as before. It is in the language of these symmetries that relativity simplified our mathematical description of the universe.

"In fact, the math becomes even nicer when the expansion of space-time is taken into account. As the physicist Freeman Dyson pointed out, any mathematician who had thought about this while studying Einstein’s theory in its early years “would have correctly predicted the expansion of the universe 20 years before it was discovered observationally by [Edwin] Hubble.”

***

'Instead, as Einstein discovered, space and time are inextricably bound. If you move too fast through space, time necessarily slows down — a consequence, he realized, of the fact that nothing travels faster than the speed of light through both space and time together. This finite speed limit forces motion through space to curb motion through time, so that measured distances and durations depend on the state of motion of the measurer. Driving alongside the sprinter actually slows your clock relative to the stopwatch of someone in the bleachers. And yet, as Einstein’s former teacher, the geometer Hermann Minkowski, showed in 1908, the “space-time interval” between two events — each person’s combined measurements of the length of the racetrack and the sprinter’s time — always stays the same regardless of one’s point of view.

***

"Instead, as Einstein discovered, space and time are inextricably bound. If you move too fast through space, time necessarily slows down — a consequence, he realized, of the fact that nothing travels faster than the speed of light through both space and time together. This finite speed limit forces motion through space to curb motion through time, so that measured distances and durations depend on the state of motion of the measurer. Driving alongside the sprinter actually slows your clock relative to the stopwatch of someone in the bleachers. And yet, as Einstein’s former teacher, the geometer Hermann Minkowski, showed in 1908, the “space-time interval” between two events — each person’s combined measurements of the length of the racetrack and the sprinter’s time — always stays the same regardless of one’s point of view.

***

"Particles, planets, people and all other symmetry-breaking stuff stems from differences that arose during the Big Bang. As the universe inflated into existence, quantum jitter in the space-time fabric grew into macroscopic variations, which evolved into the galaxies and voids and other structures seen today. If space-time’s symmetries hadn’t spontaneously broken at the outset, the universe would now be empty and uninteresting — and no one would be around to see it. Broken symmetries are necessary for existence. (my bold)

"But as the expansion of the universe accelerates due to dark energy, all its present variations will get smoothed out like wrinkles on the surface of an inflating balloon. The universe becomes “bigger and more dilute as time goes on, driving us closer and closer to the vacuum state,” Arkani-Hamed explained. Eventually, different points of view will become truly indistinguishable. “In that vacuum state we get to see that symmetry.”

"Arkani-Hamed describes the de Sitter symmetry group as an “attractor” state that the fabric of space-time naturally tends toward. But why the universe respects the 10 de Sitter symmetries only in the infinite future, while subtly breaking them in the meantime, is “a deep question,” he said. He noted that, historically, physicists have had to dig to find the hidden, approximate, eventual symmetries of nature. “The fact that they are there is clearly some deep clue.'”

Comment: This explains the importance of the concept of spacetime as real and necessary. Time is not simply a sequence of events as our minds see it. It is built into the universe, Note my bold. At the basis of reality is the quantum state. And that is where the mind of God exists.

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DAVID: It simplifies our understanding of space:

In all honesty, I find it far more confusing than simplifying!

https://www.agnosticweb.com/index.php?id=28167

QUOTE: "Particles, planets, people and all other symmetry-breaking stuff stems from differences that arose during the Big Bang. As the universe inflated into existence, quantum jitter in the space-time fabric grew into macroscopic variations, which evolved into the galaxies and voids and other structures seen today. If space-time’s symmetries hadn’t spontaneously broken at the outset, the universe would now be empty and uninteresting — and no one would be around to see it. Broken symmetries are necessary for existence. (DAVID’s bold)

DAVID: This explains the importance of the concept of spacetime as real and necessary. Time is not simply a sequence of events as our minds see it. It is built into the universe, Note my bold. At the basis of reality is the quantum state. And that is where the mind of God exists.

I am perfectly happy to accept that time as the sequence of before and after, cause and effect, is “built into the universe”, and if the BB happened, there was a sequence in which all forms of energy and matter broke up into particles, planets and eventually people. If there hadn’t been a sequence of before and after, cause and effect, and if there hadn’t been energy and matter, there would have been no you and me. I don’t know what “the quantum state” means or is, and I don’t know if whatever it is has a mind. Nor, as far as I am aware, does anybody else.

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DAVID: It simplifies our understanding of space:

dhw: In all honesty, I find it far more confusing than simplifying!

It didn't confuse Einstein

https://www.agnosticweb.com/index.php?id=28167

QUOTE: "Particles, planets, people and all other symmetry-breaking stuff stems from differences that arose during the Big Bang. As the universe inflated into existence, quantum jitter in the space-time fabric grew into macroscopic variations, which evolved into the galaxies and voids and other structures seen today. If space-time’s symmetries hadn’t spontaneously broken at the outset, the universe would now be empty and uninteresting — and no one would be around to see it. Broken symmetries are necessary for existence. (DAVID’s bold)

DAVID: This explains the importance of the concept of spacetime as real and necessary. Time is not simply a sequence of events as our minds see it. It is built into the universe, Note my bold. At the basis of reality is the quantum state. And that is where the mind of God exists.

dhw: I am perfectly happy to accept that time as the sequence of before and after, cause and effect, is “built into the universe”, and if the BB happened, there was a sequence in which all forms of energy and matter broke up into particles, planets and eventually people. If there hadn’t been a sequence of before and after, cause and effect, and if there hadn’t been energy and matter, there would have been no you and me. I don’t know what “the quantum state” means or is, and I don’t know if whatever it is has a mind. Nor, as far as I am aware, does anybody else.

I'm happy you see the concept of before and after as we all do. But in motion my experience of time may not be your time. Th at is what the article says. No one fully understands the quantum level of reality, but it makes sense to me is that is where God is.

7296 views

DAVID: This explains the importance of the concept of spacetime as real and necessary. Time is not simply a sequence of events as our minds see it. It is built into the universe, Note my bold. At the basis of reality is the quantum state. And that is where the mind of God exists.

dhw: I am perfectly happy to accept that time as the sequence of before and after, cause and effect, is “built into the universe”, and if the BB happened, there was a sequence in which all forms of energy and matter broke up into particles, planets and eventually people. If there hadn’t been a sequence of before and after, cause and effect, and if there hadn’t been energy and matter, there would have been no you and me. I don’t know what “the quantum state” means or is, and I don’t know if whatever it is has a mind. Nor, as far as I am aware, does anybody else.

DAVID: I'm happy you see the concept of before and after as we all do. But in motion my experience of time may not be your time. Th at is what the article says. No one fully understands the quantum level of reality, but it makes sense to me is that is where God is.

Most of our experiences are unlikely to be identical, since they are filtered by our subjectivity, but I guess I’m still fighting the case against “How our brains make time”, as if time didn’t exist outside humanity. As for the “quantum level of reality”, for me it’s just an expression – like “dark matter” and “God” – for something we don’t know. I can accept, though, that something we don’t know may be the home of something we don’t know. There has to be a solution to all the mysteries!

From “Far out cosmology”:
QUOTE: "All of our currently held scientific truths, from the Standard Model of elementary particles to the Big Bang to dark matter and dark energy to cosmic inflation and beyond, are only provisional. They describe the Universe extremely accurately, succeeding in regimes where all prior frameworks have failed. Yet they all have limitations to how far we can take their implications before we arrive at a place where their predictions are no longer sensible, or no longer describe reality. They are not absolute truths, but approximate, provisional ones.”

Ties in with what I have just written above, except for the statement that our currently held scientific truths...describe the Universe extremely accurately. We don't know if they are “truths”, and since nobody knows the whole “truth” about the universe, we cannot say the description is accurate, let alone extremely accurate.

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DAVID: This explains the importance of the concept of spacetime as real and necessary. Time is not simply a sequence of events as our minds see it. It is built into the universe, Note my bold. At the basis of reality is the quantum state. And that is where the mind of God exists.

dhw: I am perfectly happy to accept that time as the sequence of before and after, cause and effect, is “built into the universe”, and if the BB happened, there was a sequence in which all forms of energy and matter broke up into particles, planets and eventually people. If there hadn’t been a sequence of before and after, cause and effect, and if there hadn’t been energy and matter, there would have been no you and me. I don’t know what “the quantum state” means or is, and I don’t know if whatever it is has a mind. Nor, as far as I am aware, does anybody else.

DAVID: I'm happy you see the concept of before and after as we all do. But in motion my experience of time may not be your time. Th at is what the article says. No one fully understands the quantum level of reality, but it makes sense to me is that is where God is.

dhw: Most of our experiences are unlikely to be identical, since they are filtered by our subjectivity, but I guess I’m still fighting the case against “How our brains make time”, as if time didn’t exist outside humanity. As for the “quantum level of reality”, for me it’s just an expression – like “dark matter” and “God” – for something we don’t know. I can accept, though, that something we don’t know may be the home of something we don’t know. There has to be a solution to all the mysteries!

The bolded concepts are names we give the concepts, real or otherwise.

From “Far out cosmology”:
QUOTE: "All of our currently held scientific truths, from the Standard Model of elementary particles to the Big Bang to dark matter and dark energy to cosmic inflation and beyond, are only provisional. They describe the Universe extremely accurately, succeeding in regimes where all prior frameworks have failed. Yet they all have limitations to how far we can take their implications before we arrive at a place where their predictions are no longer sensible, or no longer describe reality. They are not absolute truths, but approximate, provisional ones.”

dhw: Ties in with what I have just written above, except for the statement that our currently held scientific truths...describe the Universe extremely accurately. We don't know if they are “truths”, and since nobody knows the whole “truth” about the universe, we cannot say the description is accurate, let alone extremely accurate.

The standard model is accurate enough it allows for predictions that are the proven: Higgs!

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A new set of papers on dark matter, string theory and inflation as related to a population of universes as predicted by string theory:

https://www.quantamagazine.org/dark-energy-may-be-incompatible-with-string-theory-20180...

"The conjectured formula — posed in the June 25 paper by Vafa, Georges Obied, Hirosi Ooguri and Lev Spodyneiko and further explored in a second paper released two days later by Vafa, Obied, Prateek Agrawal and Paul Steinhardt — says, simply, that as the universe expands, the density of energy in the vacuum of empty space must decrease faster than a certain rate. The rule appears to be true in all simple string theory-based models of universes. But it violates two widespread beliefs about the actual universe: It deems impossible both the accepted picture of the universe’s present-day expansion and the leading model of its explosive birth.

"Since 1998, telescope observations have indicated that the cosmos is expanding ever-so-slightly faster all the time, implying that the vacuum of empty space must be infused with a dose of gravitationally repulsive “dark energy.”

"In addition, it looks like the amount of dark energy infused in empty space stays constant over time (as best anyone can tell).

"But the new conjecture asserts that the vacuum energy of the universe must be decreasing.

"Vafa and colleagues contend that universes with stable, constant, positive amounts of vacuum energy, known as “de Sitter universes,” aren’t possible. String theorists have struggled mightily since dark energy’s 1998 discovery to construct convincing stringy models of stable de Sitter universes. But if Vafa is right, such efforts are bound to sink in logical inconsistency; de Sitter universes lie not in the landscape, but in the “swampland.” “The things that look consistent but ultimately are not consistent, I call them swampland,” he explained recently. “They almost look like landscape; you can be fooled by them. You think you should be able to construct them, but you cannot.”

"The conjecture, if true, would mean the density of dark energy in our universe cannot be constant, but must instead take a form called “quintessence” — an energy source that will gradually diminish over tens of billions of years.

***

"No less dramatically, the new swampland conjecture also casts doubt on the widely believed story of the universe’s birth: the Big Bang theory known as cosmic inflation. According to this theory, a minuscule, energy-infused speck of space-time rapidly inflated to form the macroscopic universe we inhabit. The theory was devised to explain, in part, how the universe got so huge, smooth and flat.

***

"To abide by the formula, the inflaton field’s energy would probably have needed to diminish too quickly to form a smooth- and flat-enough universe, he and other researchers explained. Thus, the conjecture disfavors many popular models of cosmic inflation. In the coming years, telescopes such as the Simons Observatory will look for definitive signatures of cosmic inflation, testing it against rival ideas.

***

"Whether the de Sitter swampland conjecture and future experiments really have the power to falsify string theory remains to be seen. The discovery in the early 2000s that string theory has something like 10500 solutions killed the dream that it might uniquely and inevitably predict the properties of our one universe. The theory seemed like it could support almost any observations and became very difficult to experimentally test or disprove.

***

"Vafa thinks a concerted search for definitely stable de Sitter universe models is long overdue. His conjecture is, above all, intended to press the issue. In his view, string theorists have not felt sufficiently motivated to figure out whether string theory really is capable of describing our world, instead taking the attitude that because the string landscape is huge, there must be a place in it for us, even if no one knows where. “The bulk of the community in string theory still sides on the side of de Sitter constructions [existing],” he said, “because the belief is, ‘Look, we live in a de Sitter universe with positive energy; therefore we better have examples of that type.'’”

Comment: It is time for work like this, critical of all cosmological theories

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A conclusion from recent studies:

https://phys.org/news/2018-09-gravitational-dose-reality-extra-dimensions.html:

"University of Chicago astronomers found no evidence for extra spatial dimensions to the universe based on the gravitational wave data. Their research, published in the Journal of Cosmology and Astroparticle Physics, is one of many papers in the wake of the extraordinary announcement last year that LIGO had detected a neutron star collision.

***

"Einstein's theory of general relativity explains the solar system very well, but as scientists learned more about the universe beyond, big holes in our understanding began to emerge. Two of these are dark matter, one of the basic ingredients of the universe; and dark energy, the mysterious force that's making the universe expand faster over time.

"Scientists have proposed all kinds of theories to explain dark matter and dark energy, and "a lot of alternate theories to general relativity start with adding an extra dimension," said graduate student Maya Fishbach, a coauthor on the paper. One theory is that over long distances, gravity would "leak" into the additional dimensions. This would cause gravity to appear weaker, and could account for the inconsistencies.

"The one-two punch of gravitational waves and light from the neutron star collision detected last year offered one way for Holz and Fishbach to test this theory. The gravitational waves from the collision reverberated in LIGO the morning of Aug. 17, 2017, followed by detections of gamma-rays, X-rays, radio waves, and optical and infrared light. If gravity were leaking into other dimensions along the way, then the signal they measured in the gravitational wave detectors would have been weaker than expected. But it wasn't.

"It appears for now that the universe has the same familiar dimensions—three in space and one of time—even on scales of a hundred million light-years.

"But this is just the beginning, scientists said. "There are so many theories that until now, we didn't have concrete ways to test," Fishbach said. "This changes how a lot of people can do their astronomy.'"

Comment: So much for string theory ten dimensions. All theory no substance.

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Another article on the same point: only three dimensions found:

https://www.livescience.com/63666-gravitational-waves-reveal-no-extra-dimensions.html?u...

"The study found that across vast distances in space, the universe likely operates in just the dimensions we experience on Earth. The results are also helping scientists better understand the puzzling nature of dark energy, the mysterious phenomenon behind the accelerating expansion of the universe.

"In October 2017, scientists used the Laser Interferometer Gravitational-Wave Observatory (LIGO) to detect a gravitational wave produced in the collision of two neutron stars. Dubbed GW170817, the event was also seen with traditional telescopes, allowing the scientists to simultaneously study the occurrence via gravitational waves and light waves. The dual measurements are allowing scientists to learn all sorts of things about our universe, including how many dimensions it might hold. The new results also offer additional evidence for Albert Einstein's general relativity.

"'General relativity says gravity should be working in three dimensions, and [the results] show that that's what we see," said Kris Pardo, lead author on the study and a doctoral student at Princeton University.

"While general relativity has proven so far to be spot-on in describing our universe, there's one thing it can't explain very well: why our universe's expansion is accelerating. Scientists nicknamed the cause for this acceleration "dark energy," but no one knows what it is. Some theories modify gravity to explain the expansion, suggesting gravity works differently on large scales. Many of these ideas predict that other dimensions exist, and these could be probed by gravitational waves.

"'This whole effort of looking for modified theories of gravity is in essence driven by the dark energy mystery. We're trying to find: Is there a way that we can tweak the laws of gravity to explain why the universe's expansion is speeding up?" said Tessa Baker, a cosmologist at Oxford University in England who was not involved in the study.

"According to many of these theories, if extra dimensions do exist, gravitational waves would "leak" into those dimensions, causing the waves to weaken as they made their way across the universe. The scientists in the recent study measured how far the gravitational waves and the light waves from GW170817 traveled to reach Earth, but the researchers didn't find any hints of the weakening that would be associated with extra dimensions.

"In the wake of the GW170817 event, many studies ruled out some of the modified gravity theories by calculating the speed of gravitational waves to determine their travel-time delay. This new paper is able to dismiss a whole other set of theories, Bakertold LiveScience.

"The new results exclude only large dimensions. As such, they do not place any constraints on the 10-plus dimensions predicted by string theory — a theory in physics that suggests everything is made up of tiny vibrating strings. However, the new findings do show that across scales of about 1 mile (1.6 kilometers) up to at least 80 million light-years, the universe is three-dimensional. The finding further dismisses even larger dimensions, but only if they have visible effects on physics on scales smaller than 80 million light-years.

"The researchers also used the data to calculate the lifetime of the graviton, a theoretical particle that, if it exists, conveys the force of gravity. That lifetime is at least 450 million years, the scientists found. In other words the graviton isn’t decaying into lighter particles over this time. Some modified gravity theories predict such a decay, so this calculation of the graviton’s lifetime could be used in future gravitational wave events that occur in other parts of the universe, helping to further test these theories."

Comment: No support for the 10 dimensions of string theory, but seven of those are theoretically tiny and hard to find. General relativity is supported again.

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A Danish group has disputed the findings saying background noise is not fully accounted for:

https://www.sott.net/article/399642-An-illusion-Grave-doubts-over-LIGOs-discovery-of-gr...

"The Danish group's independent checks, published in three peer-reviewed papers, found there was little evidence for the presence of gravitational waves in the September 2015 signal. On a scale from certain at 1 to definitely not there at 0, Jackson says the analysis puts the probability of the first detection being from an event involving black holes with the properties claimed by LIGO at 0.000004. That is roughly the same as the odds that your eventual cause of death will be a comet or asteroid strike - or, as Jackson puts it,"consistent with zero". The probability of the signal being due to a merger of any sort of black holes is not huge either. Jackson and his colleagues calculate it as 0.008.

"There is other evidence to suggest that at least one of the later detections came from a gravitational wave. On 17 August 2017, the orbiting Fermi telescope saw a burst of electromagnetic radiation at the same time as the LIGO and Virgo detectors picked up a signal. Analysis of all the evidence suggests that both signals came from the brutal collision of two neutron stars.

"The double whammy makes LIGO's detection seem unequivocal. Even here, though, the Danish group is dissenting. They point out that the collaboration initially registered the event as a false alarm because it coincided with what's known as a "glitch". The detectors are plagued by these short, inexplicable bursts of noise, sometimes several every hour. They seem to be something to do with the hardware with which the interferometers are built, the suspension wires and seismic isolation devices. Cornish says that LIGO analysts eventually succeeded in removing the glitch and revealing the signal, but Jackson and his collaborators are again unconvinced by the methods used, and the fact there is no way to check them.

"What are we to make of all this? Nothing, apparently. "The Danish analysis is just wrong," insists Cornish. "There were very basic mistakes." Those "mistakes" boil down to decisions about how best to analyse the raw data (see "How to catch a wave").

"Not everyone agrees the Danish choices were wrong. "I think their paper is a good one and it's a shame that some of the LIGO team have been so churlish in response," says Peter Coles, a cosmologist at Maynooth University in Ireland. Mukhanov concurs. "Right now, this is not the Danish group's responsibility. The ball is in LIGO's court," he says. "There are questions that should be answered."

"Brown thinks the Danish group's analysis is wrong, but worth engaging with. And Cornish admits the scrutiny may not be a bad thing. He and his colleagues plan to put out a paper describing the detailed properties of the LIGO noise. "It's the kind of paper we didn't really want to write because it's boring and we've got more exciting things to do." But, he adds, it is important, and increased scrutiny and criticism may in the end be no bad thing. "You do have to understand your noise.'"

Comment: It is good to have battles like this. We shall follow the battle.

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Cosmological theory says that every galaxy has a black hole at its center. Our is found:

https://bigthink.com/surprising-science/milky-way-black-hole

"Scientists have provided the first confirmation that what's at the center of the Milky Way is a supermassive black hole.

"The discovery caught the interaction of gasses and a small star spinning around the mysterious object.

"This is thought to be compelling proof of the black hole's central role in a galaxy.

"At the center of the Milky Way, about 25,000 light years away, is a faint source of radio noise. It's huge, estimated to weigh the equivalent of the 4.14 million suns. Astronomers have long suspected it's a supermassive black hole, and they've named it "Sagittarius A*."

"While astronomers can't directly observe a black hole — light doesn't escape it — they might, however, be able to see some of what goes on around one. Genzel and other scientists across the globe collected information regarding a small star called "S2" and the belt of gas, or accretion disc, that spin around Sagittarius A*. It's in the interaction between the two that the new discovery lies, and it was made possible by a breakthrough in imaging.

***

"The amazing device that ultimately allowed the team to confirm Sagittarius A*'s identity leverages the Paranal telescopes. It's called "GRAVITY," and it combines all four in a single interferometer that has the resolution of a single mirror resolution of a single mirror 130 meters in diameter.

***

"In July of this year, Genzel's team announced that they had observed via GRAVITY the center of the Milky Way, and had seen the predicted redshift, allowing them to pinpoint S2's closest approach to Sagittarius A*. New York Times reports that as the results were being read off at the Munich announcement, the room broke out into applause.

***

"Also spinning around Sagittarius A* is an accretion disc that travels at nearly 30 percent the speed of light, zooming 150 million miles around the object every 45 minutes. According to relativity, whenever S2 — or any hot object — reaches its innermost, or stable, orbit, bits of it should cross the event horizon and be instantly vaporized as they fall into the black hole, sparking brief infrared flares.

"Thanks to GRAVITY, the MPE scientists have been able to see that this actually happens at S2's closest fly-by. "GRAVITY's tremendous sensitivity has allowed us to observe the accretion processes in real time in unprecedented detail," another MPR scientist, Oliver Pfuhl, tells ESO. "It's mind-boggling to actually witness material orbiting a massive black hole at 30 percent of the speed of light."

"The predicted flares were spotted, actually, as the MPE team was observing S2 in the research that led to July's announcement, though it took until now to prepare supporting materials for publication. "We were closely monitoring S2, and of course we always keep an eye on Sagittarius A*," Pfuhl recalls. "During our observations, we were lucky enough to notice three bright flares from around the black hole — it was a lucky coincidence!"

"Genzel refers to the discovery of the flares as a "resounding confirmation of the massive black hole paradigm." Astronomers believe that black holes likely lie at the core of other galaxies as well, so this announcement has far-reaching implications. "This always was one of our dream projects but we did not dare to hope that it would become possible so soon," he concludes."

Comment: Black holes have been real in theory only until now. We can only observe effects of ours, but they should all work the same. Interestingly, Einstein did not think black holes existed even though other scientists following his theory of general relativity predicted them.

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LIGO is preparing a response:

https://www.newscientist.com/article/2184360-ligo-to-publish-new-paper-in-wake-of-new-s...

"The LIGO Scientific Collaboration, which detected gravitational waves in 2015, has announced that it will publish a detailed explanation of how it analyses the noise in its detectors.

"The announcement, on 1 November, comes in the wake of an exclusive New Scientist investigation that exposed questions about the analysis underpinning the breakthrough discovery.

***

"But detecting gravitational waves is hugely challenging. LIGO’s detectors aim to measure a shortening of space equivalent to about a thousandth of the width of a proton. This sort of measurement is swamped by natural thermal vibrations, known as noise, that make picking out the signal from a gravitational wave tricky. To deal with this, the collaboration used sophisticated analysis techniques to remove this noise their data, but these analysis techniques are being questioned.

"The claims were first aired by a group of Danish researchers a few years ago. Since then, they have published their doubts in a peer reviewed journal. The LIGO collaboration has not yet published any papers clarifying their approach in response.

"That much was common knowledge in the physics community. But the New Scientist investigation uncovered a number of irregularities, including a published data plot drawn “by eye” rather than with real data.

"LIGO now says they are in the process of preparing their paper, which will provide more information about their analysis techniques, but has not stated when this is likely to be published."

Comment: We shall keep following the issue. Everyone is sure gravitational waves exist, but that is not proof.

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Actually discovered many years ago, but now confirmed:

https://bigthink.com/surprising-science/earth-has-hidden-moon

"Hungarian astronomers have proven the existence of two "pseudo-satellites" in orbit around the earth.

These dust clouds were first discovered in the sixties, but are so difficult to spot that scientists have debated their existence since then.

"The findings may be used to decide where to put satellites in the future and will have to be considered when interplanetary space missions are undertaken.

"After more than fifty years of stargazing, debate, and controversy, scientists have confirmed the existence of two "moons" or "pseudo-satellites" made of dust orbiting the Earth. Though the clever use of mathematics, they also argue that the location of these dust clouds gives them some unique characteristics.

"The Kordylewski clouds are two dust clouds first observed by Polish astronomer Kazimierz Kordylewski in 1961. They are situated at two of the Lagrange points in Earth's orbit. These points are locations where the gravity of two objects, such as the Earth and the Moon or a planet and the Sun, equals the centripetal required to orbit the objects while staying in the same relative position. There are five of these spots between the Earth and Moon. The clouds rest at what are called points four and five, forming a triangle with the clouds and the Earth at the three corners.

"The clouds are enormous, taking up the same space in the night sky as twenty lunar discs; covering an area of 45,000 miles. They are roughly 250,000 miles away, about the same distance from us as the Moon. They are entirely comprised of specks of dust which reflect the light of the sun so faintly most astronomers that looked for them were unable to see them at all.

"The clouds themselves are probably ancient, but the model that the scientists created to learn about them suggests that the individual dust particles that comprise them can be blown away by solar wind and replaced by the dust from other cosmic sources like comet tails. This means that the clouds hardly move but are eternally changing.

***

"Lagrange points have been put forward as excellent locations for a space station or satellites like the James Webb Telescope to be put into orbit, as they would require little fuel to stay in place. Knowing about a massive dust cloud that could damage sensitive equipment already being there could save money and lives in the future. While we only know about the clouds at Lagrange points four and five right now, the study's authors suggest there could be more at the other points."

Comment: presented as points of interest. There is still much to discover.

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A battle back and forth and the LIGO folks have won. they are seeing gravitational waves, gen so far:

https://www.quantamagazine.org/studies-rescue-ligos-gravitational-wave-signal-from-the-...

" The detection of these feeble undulations in the fabric of space and time by the Laser Interferometer Gravitational-Wave Observatory (LIGO) was said to have opened a new ear on the cosmos. But the following year, a group of physicists at the Niels Bohr Institute in Copenhagen published a paper casting doubt on LIGO’s analysis. They focused their criticism on the experiment’s famous first signal, a squiggly line — representing the collision of giant black holes more than a billion light-years away — that was printed in newspapers worldwide and tattooed on bodies.

"Even as LIGO sensed more gravitational-wave signals and its founders received Nobel Prizes, the Copenhagen researchers, led by professor emeritus Andrew Jackson, claimed to have found unexplained correlations in the “noise” picked up by LIGO’s twin detectors.

***

"Now both groups have completed their studies. The new papers explain different aspects of the problem that led Jackson and his coauthors to make their claim. Both analyses definitively conclude that the claim is wrong: There are no unexplained correlations in LIGO’s noise.
“We see no justification for lingering doubts about the discovery of gravitational waves,” the authors of one of the papers, the physicists Martin Green and John Moffat of the Perimeter Institute for Theoretical Physics, said in an email.

"The pair has no direct ties to LIGO. “It’s important for science for people to do analysis of data and results independently of the group,” Moffat said, “especially for such a historic event in the history of physics.”

***

“'If LIGO did anything wrong,” he added, “it was not making it crystal-clear that pieces of that figure were illustrative and the detection claim is not based on that plot.” Jackson, however, accused LIGO scientists in an email of “misconduct” and making “the conscious decision not to inform the reader that they were violating one of the central canons of good scientific practice.”

***

"... both new papers reviewed and reanalyzed LIGO’s raw data and rediscovered the gravitational-wave signals within it, using different algorithms than LIGO’s. Other researchers have done the same."

Comment: Legitimate science allows itself to be tested by outside investigators and validated

7656 views

A new article denies more than three dimensions:

https://phys.org/news/2018-09-gravitational-dose-reality-extra-dimensions.html

"University of Chicago astronomers found no evidence for extra spatial dimensions to the universe based on the gravitational wave data. Their research, published in the Journal of Cosmology and Astroparticle Physics, is one of many papers in the wake of the extraordinary announcement last year that LIGO had detected a neutron star collision.

"The first-ever detection of gravitational waves in 2015, for which three physicists won the Nobel Prize last year, was the result of two black holes crashing together. Last year, scientists observed two neutron stars collide. The major difference between the two is that astronomers could see the aftermath of the neutron star collision with a conventional telescope, producing two readings that can be compared: one in gravity, and one in electromagnetic (light) waves.

"'This is the very first time we've been able to detect sources simultaneously in both gravitational and light waves," said Prof. Daniel Holz. "This provides an entirely new and exciting probe, and we've been learning all sorts of interesting things about the universe."

***

"Scientists have proposed all kinds of theories to explain dark matter and dark energy, and "a lot of alternate theories to general relativity start with adding an extra dimension," said graduate student Maya Fishbach, a coauthor on the paper. One theory is that over long distances, gravity would "leak" into the additional dimensions. This would cause gravity to appear weaker, and could account for the inconsistencies.

"The one-two punch of gravitational waves and light from the neutron star collision detected last year offered one way for Holz and Fishbach to test this theory. The gravitational waves from the collision reverberated in LIGO the morning of Aug. 17, 2017, followed by detections of gamma-rays, X-rays, radio waves, and optical and infrared light. If gravity were leaking into other dimensions along the way, then the signal they measured in the gravitational wave detectors would have been weaker than expected. But it wasn't.

"It appears for now that the universe has the same familiar dimensions—three in space and one of time—even on scales of a hundred million light-years.

"But this is just the beginning, scientists said. "There are so many theories that until now, we didn't have concrete ways to test," Fishbach said. "This changes how a lot of people can do their astronomy.'"

Comment: If true this finding kills the multi-dimension theories in string theory.

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Newly forming stars may emit counter forces to gravity:

https://cosmosmagazine.com/space/young-stars-push-back-to-keep-the-universe-vibrant

"The question might best perhaps be framed differently: what acts to balance the otherwise destructive force of gravity in the development of young stars?

“'If star formation happened rapidly, all stars would be bound together in massive clusters, where the intense radiation and supernova explosions would likely sterilise all the planetary systems, preventing the emergence of life,” says Crocker.

“'The conditions in these massive star clusters would possibly even prevent planets from forming in the first place.”

"In a paper published in the Monthly Notices of the Royal Astronomical Society, the researchers demonstrate that the newly formed stars themselves generate another force that works to counterbalance gravity.

"The stars coalesce from clouds interstellar dust and gas. As they do so, they radiate both ultraviolet and optical light. This collides with the remaining dust, causing the scattering of infrared light – which exerts pressure against gravity.

“'The phenomenon we studied occurs in galaxies and star clusters where there’s a lot of dusty gas that is forming heaps of stars relatively quickly,” Crocker explains.

“'In galaxies forming stars more slowly – such as the Milky Way – other processes are slowing things down. The Milky Way forms two new stars every year, on average.”

"The interaction between the two forces, he added, represents “a form of feedback that helps to keep the Universe alive and vibrant'”.

Comment: Fascinating new idea that applies to very active galaxies. The Milky Way is much older and less active so the Earth is not disturbed by any severe forces. The other point is
gravity is a very weak force so forms of light could resist it.

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The current expansion rate of the universe, named for Ed Hubble since he discovered the expanding universe, is not corroborated by two studies:

https://gizmodo.com/expanding-universe-mystery-deepens-1830664922

"One currently unexplained cosmological mystery is the “Hubble tension,” where various measurements of the universe’s expansion seem to disagree. As the story surrounding this tension gets murkier, others have begun to come up with new ideas that could explain it.

"The universe is expanding; the space between galaxies is growing. A constant named after astronomer Edwin Hubble describes how quickly this expansion occurs. Scientists now have several methods for determining the value of Hubble’s constant, but these methods have produced two values that don’t agree. For some methods, which rely on using the light from supernova and pulsing stars called Cepheid variables to determine their changing distance, it appears that objects move away from the Earth 73 kilometers per second faster for every 3.26 million additional light-years, also called a megaparsec. For other measuring methods, which rely on the electromagnetic radiation that reaches us from the early universe called the cosmic microwave background, the value is around 67 kilometers per second per megaparsec.

"Experimental errors alone don’t seem to explain the discrepant values. Attempts to explain away the difference without new physics don’t seem to hold up to scrutiny. Even so, the difference between the values isn’t at the “five-sigma” level of experimental precision required to say that the values are truly discrepant.

"But the story has gotten murkier. Most recently, a new result from scientists running the Dark Energy Survey has muddied the waters. Using measurements from supernovae, they in fact measured a Hubble constant of 67.7 kilometers per second per megaparsec, closer to the early universe measurement.

***

"..two independent teams of theoretical physicists happened to release papers addressing this tension just after the DES result came out. Both propose tweaks to our understanding of the universe’s early history. One paper reduces the tension between the two values by modifying when the period of recombination—the era a few hundred thousand years after the Big Bang when the first neutral hydrogen atoms began to form—began and ended. Another introduces “early dark energy,” some force in charge of driving the universe apart during an earlier time that has since shut off.

"Physicists already believe there are two phases of the universe expanding—one right after the Big Bang when it expanded quickly, called inflation, and the current era. “What we are saying is something similar might have happened at another time in the history of the universe,” Vivian Poulin from Johns Hopkins University told Gizmodo.

"Both of the ideas are in their infancy—they’ve only been posted in the arXiv physics preprint server, meaning that they haven’t been vetted by peer review. Additionally, both came out too soon after the DES result to cite it—and if that work holds, the theorizing might be for naught. "

Comment: All the studies use certain estimates. The mystery will clear hen those estimates are more refined.

7686 views

That is the result of a new study:

https://www.newscientist.com/article/2186909-epic-history-of-light-reveals-the-universe...

"Most of the history of the universe is a history of light – of stars blinking on and shining throughout the cosmos. Now, we have used that light, which pervades all of observable space and builds up over time, to create a timeline of stars and galaxies starting billions of years ago.

"The light of all the stars and galaxies is called the extragalactic background light. Among its properties is its ability to interfere with the high-energy gamma rays propagating through space. Some of the photons from the gamma rays smash into the photons from the background light and do not make it to our telescopes.

"So, by comparing the properties of the gamma ray sources with the number of high-energy gamma rays they actually manage to send to us, it’s possible to measure how dense the background light is, and thus the rate of formation of the stars that create it.

"An international team of researchers using the Fermi Gamma-ray Space Telescope has done just this. To get a comprehensive picture, the team looked at 740 cosmic objects that emit high-energy gamma rays. The range of distances from Earth to these objects means that they have reconstructed the history of star formation over 90 per cent of cosmic time.

"They found that star formation peaked 10 billion years ago, less than 4 billion years after the big bang. “We kind of missed the party and it’s been declining ever since,” says team member Kári Helgason at the University of Iceland.

"This is consistent with results from other surveys which measure the light coming from individual galaxies rather than all of them at once. “A galaxy survey always misses some faint galaxies,” says Helgason. “There was the possibility that we could have discovered a new mystery of missing light, but as it turned out we confirmed the picture.”

"The next step is to observe more sources of high-energy gamma rays at higher distances, says team member Abhishek Desai at Clemson University in South Carolina. These observations hinted that there might be fewer galaxies in the early universe than some models suggest, but we cannot be sure until we have higher-quality data on extremely distant gamma ray bursts."

Comment: All this means is the universe was much more active in the past. Perhaps it is much more quiet now is protective of us in our peaceful spot in our galaxy .

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Still confused with several methods not agreeing:

https://www.livescience.com/64724-hubble-constant-measured-precisely-with-quasars.html?...

"Something isn't quite right in the universe. At least based on everything physicists know so far. Stars, galaxies, black holes and all the other celestial objects are hurtling away from each other ever faster over time. Past measurements in our local neighborhood of the universe find that the universe is exploding outward faster than it was in the beginning. That shouldn't be the case, based on scientists' best descriptor of the universe.

"If their measurements of a value known as the Hubble Constant are correct, it means that the current model is missing crucial new physics, such as unaccounted-for fundamental particles, or something strange going on with the mysterious substance known as dark energy.

***

"To explain how the universe went from a tiny, hot, dense speck of soupy plasma to the vast expanse we see today, scientists have proposed what's known as the Lambda Cold Dark Matter (LCDM) model. The model puts constraints on the properties of dark matter, a kind of matter that exerts gravitational pull but emits no light, and dark energy, which seems to oppose gravity. LCDM can successfully reproduce the structure of galaxies and the cosmic microwave background — the universe's first light — as well as the amount of hydrogen and helium in the universe. But it can't explain why the universe is expanding faster now than it did early on.

"That means that either the LCDM model is wrong or the measurements of expansion rate are.
The new method aims to finally settle the expansion-rate debate,Simon Birrer, a researcher at the University of California, Los Angeles, and lead author on the new study, told Live Science.So far, the new, independent measurements confirm the discrepancy, suggesting new physics may be needed.

"To nail down Hubble's Constant, scientists had previously used several different methods. Some used supernovas in the local universe (the nearby part of the universe), and others have relied on Cepheids, or types of stars that pulsate and regularly flicker in brightness. Still others have studied the cosmic background radiation.

"The new research used a technique that involves light from quasars — extremely bright galaxies powered by massive black holes — in an effort to break the tie.

***

"Quasars don't usually shine steadily like many stars. On account of material falling into their central black holes, they change in brightness on scales of hours to millions of years. Thus, when a quasar's image is lensed into multiple copies with unequal light paths, any change in the brightness of the quasar will result in a subtle flickering between the copies, as light from certain copies takes a touch longer to reach Earth.

"From this discrepancy, scientists could precisely determine how far we are from both the quasar and the intermediary galaxy. To calculate the Hubble Constant, astronomers then compared that distance to the object's redshift, or the shift in wavelengths of light toward the red end of the spectrum (which shows how much the object's light has stretched as the universe expands).

***

"'Images of quasars that appear four times are very rare — there are maybe only 50 to 100 across the whole sky, and not all are bright enough to be measured," Birrer told Live Science. "Doubly- lensed systems, however, are more frequent by about a factor of five."

"The new results from a doubly-lensed system, combined with three other previously measured quadruple-lensed systems, put the value for the Hubble Constant at 72.5 kilometers per second per megaparsec; that's in agreement with other local universe measurements, but still around 8 percent higher than measurements from the distant universe (the older, or early, universe). As the new technique is applied to more systems, researchers will be able to home in on the exact difference between distant (or early) universe and local (more recent) universe measurements.

***

"Accurately measuring the Hubble Constant helps scientists understand more than just how fast the universe is flying apart. The value is imperative in determining the age of the universe and the physical size of distant galaxies. It also gives astronomers clues as to the amount of dark matter, and dark energy, out there."

Comment: the Hubble is still in trouble. Once inflation stopped (if it existed, which still seems likely) why did slow expansion persist? Answers await.

7651 views

WIMPS, very weak particles which were supposed to be related have not been found:

https://www.forbes.com/sites/startswithabang/2019/02/22/the-wimp-miracle-is-dead-as-dar...

"As of 2019, we've met with tremendous success on those fronts that have confirmed the Standard Model in ways that both theorists and experimentalists could have only dreamed of half a century ago. Detectors at colliders and isolated, underground facilities have led the way forward.

***

"We understand how the Standard Model particles behave. We have solid predictions for how they should interact through all of the fundamental forces, and experimental confirmation of those theories. We also have extraordinary constraints on how they're permitted to interact in a beyond-the-Standard-Model fashion. Because of our constraints from accelerators, cosmic rays, decay experiments, nuclear reactors and more, we've been able to rule out many possible ideas that have been theorized.

"When it comes to what might make up the dark matter, however, all we have are the astrophysical observations and our theoretical work, in tandem, to guide us. The possible theories that we've come up with include a huge number of dark matter candidates, but none that have garnered any experimental support.

***

"The most sought-after dark matter candidate is the WIMP: the Weakly Interacting Massive Particle. In the early days — i.e., back in the 1970s — it was realized that some particle physics theories that predicted new particles beyond the Standard Model could eventually produce new types of stable, neutral particles if there were some new type of parity (a type of symmetry) that prevented them from decaying.

***

"If there is WIMP dark matter, it must be weaker than the weak interaction permits to comprise 100% of the dark matter. Additionally, the LHC should not detectably produce it.

***

"The WIMP miracle may be dead and gone, as particles interacting through the weak force at the electroweak scale have been disfavored by both colliders and direct detection. The idea of WIMP dark matter, however, lives on. We just have to remember, when you hear WIMP, we include dark matter that's weaker and wimpier than even the weak interactions will allow. There is undoubtedly something new out there in the Universe, waiting to be discovered.

"The WIMP miracle is over. But we still might get the best miracle of all: if these experiments turn up something beyond a null result. The only way to know is to look."

Comment: Something must cause dark matter. Keep looking.

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And they may help with planet formation:

https://www.quantamagazine.org/wandering-space-rocks-help-solve-mysteries-of-planet-for...

"In 2017, a weirdly shaped rock with a strangely erratic orbit swept through the solar system, leaving as quickly as it arrived. Astronomers soon realized that it was not from around here. It punched through the planets’ orbital plane from the top down, like a dart thrown at the concentric rings of a dartboard, and it moved super fast, way too quickly to be caught in the sun’s gravity. It was also extremely dark and seemed oddly elongated, but because it was so speedy, many of its properties will remain forever mysterious.

"But it turns out that the object, the first interstellar asteroid ever observed, was not unique. It may not even be all that rare. Astronomers are coming to realize that objects like it may pepper the galaxy, perhaps in such great numbers that they influence the formation of larger worlds, maybe even entire planetary systems — including our own.

'The appearance of the asteroid, which has been named ‘Oumuamua, was a dramatic demonstration of a sea change in astronomy: the recognition that the solar system does not exist in a vacuum, at least metaphorically. No planet is an island, and no star forms in isolation. The cosmos is full of stuff that interacts across distances and time spans far greater than researchers have long appreciated, from unimaginably vast jets of gas flowing through interstellar space to ‘Oumuamua-style planetoid crumbs scattered like dandelion seeds in the wind.

"This realization is changing the way astronomers think about how star systems form. Researchers who study the birth of planetary systems have not previously considered things like astrophysical gas flows, for instance.

***

"In a paper published in April in The Astrophysical Journal Letters, Bannister and Pfalzner argue that rocks like ‘Oumuamua might be catalysts for planet formation. There are probably uncountable billions of such objects sailing through the cosmos, they say. When one intersects with a billowing envelope of gas and dust surrounding a young star, it might cause turbulence and shear that stirs the gas, sculpting it into patterns that later form planets.

"In addition, they argue that ‘Oumuamua-like items might move at the right speed to become permanent residents. Infant solar systems could catch great numbers of these interstellar travelers. In their new homes, these immigrants would begin to gather smaller pebbles and dust grains, growing into larger objects. In doing so, they would provide the building blocks for pebble accretion, a theory that explains how large objects can grow very quickly into planets.

“'It’s not a huge amount of mass; it’s more their presence in the disk that would trigger it,” Pfalzner said. “It’s a seed stage. You can grow a huge tree, but it always starts from a tiny seed. It’s not the mass of the seed. It’s the potential, if you will.”

***

"Stewart’s work on chondrules and Bannister and Pfalzner’s ideas about planet formation are part of an emerging understanding that even in space, everything is connected. “You have to go through a huge amount of different fields in astrophysics,” Pfalzner said: “the interstellar medium, molecular clouds, formation of stars, the disks around them, the formation of planets.”

"Data from future observatories like the Large Synoptic Survey Telescope (LSST) could intensify the need to think across many different size scales. The LSST might be able to resolve tiny pebbles in our solar system, allowing astronomers to search for more ‘Oumuamua-like objects. “I think it’s really, really exciting if our solar system is chock-full of these interstellar fragments that have come from other solar systems, that there are bits of other solar systems floating around,” Byrne said. “LSST is going to open this whole new world,” one that connects our solar system to other solar systems throughout the cosmos across time and space."

Comment: Much about planet and solar system formation is not known. We are concerned about asteroids hitting the Earth, but these other rocks flying about and coming into the solar system cannot be blocked. Luckily there is lots of empty space for them in which to roam about.

7294 views

Ethan Siegel's definition of scientific truth is that there are theories that fit observation, but no more:

https://www.forbes.com/sites/startswithabang/2019/07/13/ask-ethan-what-does-truth-mean-...

"In many ways, the human endeavor of science is the ultimate pursuit of truth. By asking the natural world and Universe questions about itself, we seek to gain an understanding of what the Universe is like, what the rules that govern it are, and how things came to be the way they are today. Science is the full suite of knowledge that we gain from observing, measuring, and performing experiments that test the Universe, but it's also the process through which we perform those investigations. It might be easy to see how we gain knowledge from that endeavor, but how do scientists arrive at the idea of a scientific truth?

***

"There are no absolute truths in science; there are only approximate truths.

"Whether a statement, theory, or framework is true or not depends on quantitative factors and how closely you examine or measure the results.

"Every scientific theory has a finite range of validity: inside that range, the theory is indistinguishable from true, outside of that range, the theory is no longer true.

***

"Science is not about finding the absolute truth of the Universe. No matter how much we'd like to know what the fundamental nature of reality is, from the smallest subatomic scales to the largest cosmic ones and beyond, this is not something science can deliver. All of our scientific truths are provisional, and we must recognize that they are only models or approximation of reality.

"Even the most successful scientific theories imaginable will, by their very nature, have a limited range of validity. But we can theorize whatever we like, and when a new theory meets the following three criteria:

"it achieves all of the successes of the prevailing, pre-existing theory,

"it succeeds where the current theory is known to fail,

"and it makes novel predictions for hitherto unmeasured phenomena, distinct from the prior theory, that pass the critical observational or experimental tests,

"it will supersede the current one as our best approximation of a scientific truth.

"All of our currently held scientific truths, from the Standard Model of elementary particles to the Big Bang to dark matter and dark energy to cosmic inflation and beyond, are only provisional. They describe the Universe extremely accurately, succeeding in regimes where all prior frameworks have failed. Yet they all have limitations to how far we can take their implications before we arrive at a place where their predictions are no longer sensible, or no longer describe reality. They are not absolute truths, but approximate, provisional ones.

"No experiment can ever prove that a scientific theory is true; we can only demonstrate that its validity either extends or fails to extend to whatever regime we test it in. The failure of a theory is actually the ultimate scientific success: an opportunity to find an even better scientific truth to approximate reality. It's being wrong in the best way imaginable."

Comment: This view of science and truth requires observation of something. Multiverse conjectures cannot do this, and are worthless.

7304 views

A new approach to understanding the early universe:

https://www.quantamagazine.org/the-origin-of-time-bootstrapped-from-fundamental-symmetr...

“'We look at patterns in space today, and we infer a cosmological history in order to explain them.”

"One curious pattern cosmologists have known about for decades is that space is filled with correlated pairs of objects: pairs of hot spots seen in telescopes’ maps of the early universe; pairs of galaxies or of galaxy clusters or superclusters in the universe today; pairs found at all distances apart. You can see these “two-point correlations” by moving a ruler all over a map of the sky. When there’s an object at one end, cosmologists find that this ups the chance that an object also lies at the other end.

"The simplest explanation for the correlations traces them to pairs of quantum particles that fluctuated into existence as space exponentially expanded at the start of the Big Bang. Pairs of particles that arose early on subsequently moved the farthest apart, yielding pairs of objects far away from each other in the sky today. Particle pairs that arose later separated less and now form closer-together pairs of objects. Like fossils, the pairwise correlations seen throughout the sky encode the passage of time — in this case, the very beginning of time.

"Cosmologists believe that rare quantum fluctuations involving three, four or even more particles should also have occurred during the birth of the universe. These presumably would have yielded more complicated configurations of objects in the sky today: triangular arrangements of galaxies, along with quadrilaterals, pentagons and other shapes. Telescopes haven’t yet spotted these statistically subtle “higher-point” correlations, but finding them would help physicists better understand the first moments after the Big Bang.

"Yet theorists have found it challenging even to calculate what the signals would look like — until recently. In the past four years, a small group of researchers has approached the question in a new way. They have found that the form of the correlations follows directly from symmetries and other deep mathematical principles.

"The physicists employed a strategy known as the bootstrap, a term derived from the phrase “pick yourself up by your own bootstraps” (instead of pushing off of the ground). The approach infers the laws of nature by considering only the mathematical logic and self-consistency of the laws themselves, instead of building on empirical evidence. Using the bootstrap philosophy, the researchers derived and solved a concise mathematical equation that dictates the possible patterns of correlations in the sky that result from different primordial ingredients.

***

"There’s no “time” variable anywhere in the new bootstrapped equation. Yet it predicts cosmological triangles, rectangles and other shapes of all sizes that tell a sensible story of quantum particles arising and evolving at the beginning of time.

***

"In 1980, the cosmologist Alan Guth, pondering a number of cosmological features, posited that the Big Bang began with a sudden burst of exponential expansion, known as “cosmic inflation.” Two years later, many of the world’s leading cosmologists gathered in Cambridge, England, to iron out the details of the new theory. Over the course of the three-week Nuffield workshop, a group that included Guth, Stephen Hawking, and Martin Rees, the future Astronomer Royal, pieced together the effects of a brief inflationary period at the start of time. By the end of the workshop, several attendees had separately calculated that quantum jitter during cosmic inflation could indeed have happened at the right rate and evolved in the right way to yield the universe’s observed density variations.

***

"Recall that an inflating universe would have had almost, but not exactly, the geometry of de Sitter space. In perfect de Sitter space, nothing changes in time; the whole outwardly stretching geometry exists at once. The inflaton field weakly broke this temporal symmetry by slowly dropping in energy over time, initiating change. Baumann sees this as necessary for creating cosmology. “In cosmology by definition we want something that’s evolving in time,” he said. “In de Sitter space, there’s no evolution. It’s interesting that we live very close to that point.” He compared the primordial universe to a system like water or a magnet very near the critical point where it undergoes a phase transition. “We live in a very special place,” he said." (my bold)

Comment: I skipped much of the current research which is very still uncertain. Note that quantum mechanics are at the basis of this early universe research. It supports my statements that this universe is based on quantum particles. Our unusual status is noted in the bolded statement. All indications of design .

7063 views

The problem is the discovery that the local neighborhood is all flowing in one direction, which skews the supernova measurement of the red shift. Objects we move toward will have a shorter distance measurement while ones in the opposite direction will appear further away:

http://backreaction.blogspot.com/2019/11/dark-energy-might-not-exist-after-all.html

"To briefly remind you, dark energy is what speeds up the expansion of the universe.

***

"The most important evidence we have for the existence of dark energy comes from supernova redshifts. Saul Perlmutter and Adam Riess won a Nobel Prize for this observation in 2011. It’s this Nobel-prize winning discovery which the new paper calls into question.

***

"Now, Perlmutter and Riess did their analysis 20 years ago and they used a fairly small sample of about 110 supernovae. Meanwhile, we have data for more than 1000 supernovae. For the new paper, the researchers used 740 supernovae from the JLA catalogue. But they also explain that if one just uses the data from this catalogue as it is, one gets a wrong result. The reason is that the data has been “corrected” already.

***

"What they found is that the best fit to the data is that the redshift of supernovae is not the same in all directions, but that it depends on the direction. This direction is aligned with the direction in which we move through the cosmic microwave background. And – most importantly – you do not need further redshift to explain the observations.

"If what they say is correct, then it is unnecessary to postulate dark energy which means that the expansion of the universe might not speed up after all.

"Why didn’t Perlmutter and Riess come to this conclusions? They could not, because the supernovae that they looked were skewed in direction. The ones with low redshift were in the direction of the CMB dipole; and high redshift ones away from it. With a skewed sample like this, you can’t tell if the effect you see is the same in all directions.*

***

"This paper, I have to emphasize, has been peer reviewed, is published in a high quality journal, and the analysis meets the current scientific standard of the field. It is not a result that can be easily dismissed and it deserves to be taken very seriously, especially because it calls into question a Nobel Prize winning discovery. This analysis has of course to be checked by other groups and I am sure we will hear about this again, so stay tuned."

Comment: The original Nobel prize paper predicted that the universe was expanding faster and faster. This paper says the Hubble Constant of expansion is the same steady rate we thought it was. Wow. True science is self-correcting. I wish Darwinism was.

6910 views

http://backreaction.blogspot.com/2019/11/dark-energy-might-not-exist-after-all.html

DAVID: To briefly remind you, dark energy is what speeds up the expansion of the unive

QUOTES: "If what they say is correct, then it is unnecessary to postulate dark energy which means that the expansion of the universe might not speed up after all.”

"Why didn’t Perlmutter and Riess come to this conclusion? They could not, because the supernovae that they looked were skewed in direction. The ones with low redshift were in the direction of the CMB dipole; and high redshift ones away from it. With a skewed sample like this, you can’t tell if the effect you see is the same in all directions.”

QUOTE: "This paper, I have to emphasize, has been peer reviewed, is published in a high quality journal, and the analysis meets the current scientific standard of the field. It is not a result that can be easily dismissed and it deserves to be taken very seriously, especially because it calls into question a Nobel Prize winning discovery. This analysis has of course to be checked by other groups and I am sure we will hear about this again, so stay tuned."

DAVID: The original Nobel prize paper predicted that the universe was expanding faster and faster. This paper says the Hubble Constant of expansion is the same steady rate we thought it was. Wow. True science is self-correcting. I wish Darwinism was.

Thank you for this very important article.The existence of dark matter (i.e. matter which nobody knows anything about) has been questioned for years, as has the theory of speeding expansion. I recall many articles on the subject published by the Society for Interdisciplinary Studies – an organization much derided by the scientific establishment precisely because they kept challenging orthodox views. Eventually no doubt scientists will question the theory of the Big Bang. Your customary snipe at Darwinism is totally unnecessary and irrelevant, and in any case many scientists have challenged Darwin’s ideas on random mutations and gradualism.

6901 views

http://backreaction.blogspot.com/2019/11/dark-energy-might-not-exist-after-all.html

DAVID: To briefly remind you, dark energy is what speeds up the expansion of the unive

QUOTES: "If what they say is correct, then it is unnecessary to postulate dark energy which means that the expansion of the universe might not speed up after all.”

"Why didn’t Perlmutter and Riess come to this conclusion? They could not, because the supernovae that they looked were skewed in direction. The ones with low redshift were in the direction of the CMB dipole; and high redshift ones away from it. With a skewed sample like this, you can’t tell if the effect you see is the same in all directions.”

QUOTE: "This paper, I have to emphasize, has been peer reviewed, is published in a high quality journal, and the analysis meets the current scientific standard of the field. It is not a result that can be easily dismissed and it deserves to be taken very seriously, especially because it calls into question a Nobel Prize winning discovery. This analysis has of course to be checked by other groups and I am sure we will hear about this again, so stay tuned."

DAVID: The original Nobel prize paper predicted that the universe was expanding faster and faster. This paper says the Hubble Constant of expansion is the same steady rate we thought it was. Wow. True science is self-correcting. I wish Darwinism was.

dhw: Thank you for this very important article.The existence of dark matter (i.e. matter which nobody knows anything about) has been questioned for years, as has the theory of speeding expansion. I recall many articles on the subject published by the Society for Interdisciplinary Studies – an organization much derided by the scientific establishment precisely because they kept challenging orthodox views. Eventually no doubt scientists will question the theory of the Big Bang. Your customary snipe at Darwinism is totally unnecessary and irrelevant, and in any case many scientists have challenged Darwin’s ideas on random mutations and gradualism.

Real science is self-correcting as the article shows. You fell into the same stance as always. I point out that Darwinism scientists keep defending what cannot be longer defended using this articled as an example. Dawkins, Coyne, Graur and many others are still blathering. Do you realize Darwinism is a religion? That's what I'm complaining about. And to your point, there are many articles challenging the Big Bang. I read one yesterday.

6910 views

dhw: Thank you for this very important article.The existence of dark matter (i.e. matter which nobody knows anything about) has been questioned for years, as has the theory of speeding expansion. I recall many articles on the subject published by the Society for Interdisciplinary Studies – an organization much derided by the scientific establishment precisely because they kept challenging orthodox views. Eventually no doubt scientists will question the theory of the Big Bang. Your customary snipe at Darwinism is totally unnecessary and irrelevant, and in any case many scientists have challenged Darwin’s ideas on random mutations and gradualism.

DAVID: Real science is self-correcting as the article shows. You fell into the same stance as always. I point out that Darwinism scientists keep defending what cannot be longer defended using this articled as an example. Dawkins, Coyne, Graur and many others are still blathering. Do you realize Darwinism is a religion? That's what I'm complaining about. And to your point, there are many articles challenging the Big Bang. I read one yesterday.

The quotes you have given us have nothing to do with Darwinism. The subject is dark energy/matter, which I have extended to the Big Bang. See also the James A. Shapiro thread, where again you tried to switch the subject to Darwin. It makes for messy threads!

6938 views

dhw: Thank you for this very important article.The existence of dark matter (i.e. matter which nobody knows anything about) has been questioned for years, as has the theory of speeding expansion. I recall many articles on the subject published by the Society for Interdisciplinary Studies – an organization much derided by the scientific establishment precisely because they kept challenging orthodox views. Eventually no doubt scientists will question the theory of the Big Bang. Your customary snipe at Darwinism is totally unnecessary and irrelevant, and in any case many scientists have challenged Darwin’s ideas on random mutations and gradualism.

DAVID: Real science is self-correcting as the article shows. You fell into the same stance as always. I point out that Darwinism scientists keep defending what cannot be longer defended using this articled as an example. Dawkins, Coyne, Graur and many others are still blathering. Do you realize Darwinism is a religion? That's what I'm complaining about. And to your point, there are many articles challenging the Big Bang. I read one yesterday.

dhw: The quotes you have given us have nothing to do with Darwinism. The subject is dark energy/matter, which I have extended to the Big Bang. See also the James A. Shapiro thread, where again you tried to switch the subject to Darwin. It makes for messy threads!

My point is the same. Current Darwinism is a religion. If others lurk here, I am trying educate them.

6897 views

Current theory, well accepted, is that in the beginning matter and antimatter were in equal amounts. Today matter dominates and we are here. Why?:

https://wattsupwiththat.com/2020/02/05/how-the-tiniest-particles-in-our-universe-saved-...

"According to the Big Bang theory of modern cosmology, matter was created with an equal amount of anti-matter. If it had stayed that way, matter and anti-matter should have eventually met and annihilated one to one, leading up to a complete annihilation.

"But our existence contradicts this theory. To overcome a complete annihilation, the Universe must have turned a small amount of anti-matter into matter creating an imbalance between them. The imbalance needed is only a part in a billion. But it has remained a complete mystery when and how the imbalance was created.

***

"Since matter and anti-matter have the opposite electrical charges, they cannot turn into each other, unless they are electrical neutral. Neutrinos are the only electrical neutral matter particles we know, and they are the strongest contender to do this job. A theory many researchers support is that the Universe went through a phase transition so that neutrinos could reshuffle matter and anti-matter.

“'A phase transition is like boiling water to vapor, or cooling water to ice. The behavior of matter changes at specific temperatures called critical temperature. When a certain metal is cooled to a low temperature, it loses electrical resistance completely by a phase transition, becoming a superconductor.

***

"The authors discuss the possibility that a phase transition after inflation led to a tiny imbalance between the amount of matter and anti-matter, so that some matter could survive a near-complete annihilation. Such a phase transition is likely to lead to a network of “rubber-band”-like objects called cosmic strings, that would produce ripples of space-time known as gravitational waves. These propagating waves can get through the hot and dense Universe and reach us today, 13.8 billion years after the phase transition. Such gravitational waves can most likely be discovered by current and future experiments.

***

“'The recent discovery of gravitational waves opens up a new opportunity to look back further to a time, as the Universe is transparent to gravity all the way back to the beginning. When the Universe might have been a trillion to a quadrillion times hotter than the hottest place in the Universe today, neutrinos are likely to have behaved in just the way we require to ensure our survival. We demonstrated that they probably also left behind a background of detectable gravitational ripples to let us know,” says paper co-author Graham White,..."

Comment: A very complex fine-tuned manipulation or we would not be here. Looks like God, the chief engineer, had His hand in this guiding the result needed from the available particles initially created. Cosmic strings are not string theory, but another theory related to phase transitions:

"Cosmic strings are hypothetical 1-dimensional topological defects which may have formed during a symmetry breaking phase transition in the early universe when the topology of the vacuum manifold associated to this symmetry breaking was not simply connected.Wikipedia"

6665 views

Fred Hoyle had a fusion in stars method of existing elements. This one uses neutron star collisions:

https://www.scientificamerican.com/article/carbon-conundrum-experiment-aims-to-re-creat...

"Our current understanding of the triple-alpha process largely came from astronomer Fred Hoyle, who famously predicted, in 1954, that a special excited state of carbon-12 must arise during synthesis. Later scientists observed this so-called Hoyle state and confirmed that the carbon then emitted gamma rays to de-excite down to its ground, or stable, state.

"Scientists have long suspected that other particles might play a role in that de-excitation, especially neutrons, which carry no electrical charge and can penetrate nuclei and take away extra energy. Measuring neutron energies has been difficult, however. A few years ago, physicist Lee Sobotka of Washington University in St. Louis decided the time was right to develop an experiment to test this idea.

***

“'What we are doing here is to measure the cross section, or probability, of an inverse reaction of the original triple-alpha process,” Sobotka says. Because the Hoyle state can exist for only a blink of an eye, it is almost impossible to directly measure it. In the reverse reaction, neutrons will hit carbon nuclei, excite them to the Hoyle state, produce alpha particles and then leave the scene with a lower energy. “It’s a clever approach to measuring the probability that the Hoyle state is de-excited in a collision with the neutron by performing the inverse measurement,” says Martin Freer of the University of Birmingham in England, who is not involved in the experiment.

***

"Once the data are available, the next step will be to invite astrophysicists to join the conversation and interpret the cosmic environment needed for such neutron-induced carbon formation, Sobokta says. The scenario could be quite different from the quiet burning processes in a star. It may be “a supernova or a neutron-star merger,” in which not only the density of particles is higher but more neutrons can be present, Freer says. Yet carbon created in such cataclysmic processes may not necessarily increase the total amount of carbon in the universe significantly because they act “as seeds for the synthesis of heavier elements produced in these explosions,” he notes. In other words, these carbon atoms may get absorbed in creating other members of the periodic table."

Comment: The research goes on and the idea is still based on Hoyle's concept. Carbon is the basis of the biochemistry of life and there is lots of it as part of the fine tuning of the universe for life.

6667 views

The luminous disk, plus the surrounding gas disc is now measured:

https://www.sciencenews.org/article/astronomers-have-found-edge-milky-way-size

"Astronomers have long known that the brightest part of the Milky Way, the pancake-shaped disk of stars that houses the sun, is some 120,000 light-years across. Beyond this stellar disk is a disk of gas. A vast halo of dark matter, presumably full of invisible particles, engulfs both disks and stretches far beyond them . But because the dark halo emits no light, its diameter is hard to measure.

"Now, Alis Deason, an astrophysicist at Durham University in England, and her colleagues have used nearby galaxies to locate the Milky Way’s edge. The precise diameter is 1.9 million light-years, give or take 0.4 million light-years, the team reports February 21 in a paper posted at arXiv.org.

***

"To find the Milky Way’s edge, Deason’s team conducted computer simulations of how giant galaxies like the Milky Way form. In particular, the scientists sought cases where two giant galaxies arose side by side, like the Milky Way and Andromeda, our nearest giant neighbor, because each galaxy’s gravity tugs on the other. The simulations showed that just beyond the edge of a giant galaxy’s dark halo, the velocities of small nearby galaxies drop sharply.

"Using existing telescope observations, Deason and her colleagues found a similar plunge in the speeds of small galaxies near the Milky Way. This occurred at a distance of about 950,000 light-years from the Milky Way’s center, marking the galaxy’s edge, the scientists say. The edge is 35 times farther from the galactic center than the sun is.

"Although dark matter makes up most of the Milky Way’s mass, the simulations reveal that stars should also exist at these far-out distances. “Both have a well-defined edge,” Deason says. “The edge of the stars is very sharp, almost like the stars just stop at a particular radius.'”

"The measurement should also help astronomers tease out other galactic properties. For instance, the larger the Milky Way, the more massive it is — and the more galaxies there should be revolving around it, says Rosemary Wyse, an astronomer at Johns Hopkins University who was not part of the new work. So far, there are about 60 known Milky Way satellites, but astronomers suspect that many more await discovery."

Comment: Wow! We sure are big, but the Earth is out in a safe place two-thirds of the way out the second spiral arm. It makes us one of the bigger galaxies controlling our own local group. And life is here. Is the size related?

6601 views

Inflation won't fit into string theory:

https://www.scientificamerican.com/article/will-string-theory-finally-be-put-to-the-exp...

"Theorists have had difficulty, though, showing how, or if, inflation works in string theory. The most promising road to doing so—the so-called KKLT construction—does not convince everyone. “It depends who you ask,” says Suddhasattwa Brahma, a cosmologist at McGill University. “It has been a lingering doubt in the back of the minds of many in string theory: Does it really work?”
In 2018 a group of string theorists took a series of suggestive results and argued that this difficulty reflected an impossibility—that perhaps inflation just cannot happen in the theory.

"This so-called de Sitter swampland conjecture claimed that any version of the concept that could describe de Sitter space—a term for the kind of universe in which we expect inflation to take place—would have some kind of technical flaw that put it in a “swampland” of rejected theories.

"No one has proved the swampland conjecture, and several string theorists still expect that the final form of the theory will have no problem with inflation. But many believe that although the conjecture might not hold up rigidly, something close to it will. Brahma hopes to refine the swampland conjecture to something that would not bar inflation entirely.

***

"These kinds of questions led Vafa and his Harvard collaborator Alek Bedroya to seek out a physics-based reason that could justify the swampland conjecture. They found a candidate in a surprising place. It turns out that inflation already has an unsolved problem looking for a solution: theorists have not all agreed on what happens to the very tiniest quantum details when expansion occurs and magnifies the static of the vacuum.

"Physicists lack a working theory that describes the world below the level of the so-called Planck length, an extremely minute distance where they expect the quantum side of gravity to appear. Proponents of inflation have typically had to assume that they can one day work those “trans-Planckian” details into it and that they will not make a big difference to any predictions. But how that step will happen remains an open question.

***

From Rob Sheldon at uncommon descent: "Our physics color commentator, Rob Sheldon, author of The Long Ascent I and The Long Ascent II, offers, “This article explains precisely why thousands of theoretical physicists have not made any progress in 40 years. One hopelessly ad hoc and unsupported theory (inflation) conflicts with another hopelessly unphysical theory (string theory) and then others purport to resolve the difficulty by resorting to highly questionable phenomena (gravity waves)."

https://uncommondescent.com/intelligent-design/has-a-way-been-found-to-test-string-theo...

Comment: Still fun and games in theoretical cosmology with no good theory in sight. God created and evolved the universe in His own hidden way.

6605 views

It can be flat, concave or convex. Convex is be ruled out:

https://www.quantamagazine.org/black-holes-prove-that-anti-de-sitter-space-time-is-unst...

"The three simplest solutions to Einstein’s vacuum equations are the most symmetric ones — those in which the curvature of space-time is the same everywhere. In Minkowski space-time, where the cosmological constant is zero, the universe is perfectly flat. In de Sitter space-time, where the cosmological constant has a positive value, the universe is shaped like a sphere. And when the cosmological constant is negative, you get AdS space-time, which has a saddle shape. In the early days of cosmology, scientists wondered which one of these three space-times describes our universe.

***

"Here’s the proof of instability: Moschidis showed that when he adds even a minuscule amount of matter to an AdS space-time, a black hole (or black holes) will inexorably form. However, AdS space-time has, by definition, uniform curvature everywhere, which means it cannot harbor space-contorting objects like black holes. “If you perturb AdS space-time and wait a sufficient time,” Moschidis said, “you’ll end up with a different geometry — one that contains black holes — and it’s no longer AdS. That’s what we mean by unstable.'”

Comment: Getting rid of convex, saddle-shaped space time, simplifies the issue of getting real quantum gravity understood.

6361 views

Galaxies like the Milky Way were not thought to be as old as this one:

https://www.newscientist.com/article/2243924-weve-found-the-oldest-ever-galaxy-that-loo...

"A galaxy from the early universe has been found to be far smoother than expected, which is evidence for a speedy sort of galaxy formation never spotted before. And it could mean that galaxies like the Milky Way may have started taking shape far earlier in the universe’s history than we thought they could.

"Our current models of the universe suggest that in the first few billion years after the big bang, galaxies formed as a result of clumps of dark matter attracting hot gas, which eventually formed stars. When young, we expect galaxies formed like this to be lumpy and misshapen.

"But that isn’t always the case. Marcel Neeleman at the Max Planck Institute for Astronomy in Germany and his colleagues used the Atacama Large Millimeter/submillimeter Array in Chile to spot a galaxy in the early universe that isn’t lumpy. This one dates to just 1.5 billion years after the big bang.

"Instead, it appears to be a smooth, rotating disc that looks more like our own spiral galaxy than the typical galaxies of the early cosmos. Officially called DLA0817g and dubbed the Wolfe Disk by the researchers, it formed 2.5 billion years earlier than the next oldest disc galaxy we have seen.

“'The other extremely early galaxies we’ve seen just look like train wrecks, with clumps of gas everywhere, but this one is not like that,” says Neeleman. But if it formed from hot gas, it wouldn’t have had enough time since the big bang to smooth out its clumps and form a defined disc.

"Instead, the researchers think it formed via a process called cold accretion, where gas flows smoothly into the galaxy along dense filaments instead of falling in clumps. This process is expected to be gentler, allowing the gas to settle into a disc more quickly in the early universe.

"This is the first galaxy that we have seen in the early universe that seems to have formed this way, and we will need to find more to determine if it is a common process. “We don’t think that this is an extraordinary galaxy,” says Neeleman. “We think it’s quite normal and we should be able to find a whole bunch more.'”

Comment: Raises the question of whether the universe was programmed in advance for large flat spiral galaxies, one of which could evolve to the point of allowing a planet which would support the appearance of life.

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We are surrounded by a herd of minor galaxies:

https://www.sciencedaily.com/releases/2020/04/200406140110.htm

"Just like we orbit the sun and the moon orbits us, the Milky Way has satellite galaxies with their own satellites. Drawing from data on those galactic neighbors, a new model suggests the Milky Way should have an additional 100 or so very faint satellite galaxies awaiting discovery.

***

"the Large Magellanic Cloud (LMC), a relatively large satellite galaxy visible from the Southern Hemisphere, is thought to have brought at least six of its own satellite galaxies with it when it first approached the Milky Way, based on recent measurements from the European Space Agency's Gaia mission.

"Astrophysicists believe that dark matter is responsible for much of that structure, and now researchers at the Department of Energy's SLAC National Accelerator Laboratory and the Dark Energy Survey have drawn on observations of faint galaxies around the Milky Way to place tighter constraints on the connection between the size and structure of galaxies and the dark matter halos that surround them. At the same time, they have found more evidence for the existence of LMC satellite galaxies and made a new prediction: If the scientists' models are correct, the Milky Way should have an additional 150 or more very faint satellite galaxies awaiting discovery by next-generation projects.

***

Thanks to the Sloan Digital Sky Survey and more recent discoveries by projects including the Dark Energy Survey (DES), the number of known satellite galaxies has climbed to about 60.

***

"Those simulations, originally run by Yao-Yuan Mao, a former graduate student of Wechsler's who is now at Rutgers University, model the formation of dark matter structure that permeates the Milky Way, including details such as smaller dark matter clumps within the Milky Way that are expected to host satellite galaxies. To connect dark matter to galaxy formation, the researchers used a flexible model that allows them to account for uncertainties in the current understanding of galaxy formation, including the relationship between galaxies' brightness and the mass of dark matter clumps within which they form.

***
"And there could be more discoveries to come: If the simulations are correct, Nadler said, there are around 100 more satellite galaxies -- more than double the number already discovered -- hovering around the Milky Way. The discovery of those galaxies would help confirm the researchers' model of the links between dark matter and galaxy formation, he said, and likely place tighter constraints on the nature of dark matter itself."

Comment: We are a giant galaxy with many satellites held by our gravity pull but also by dark matter gravity. The issue for me is why did God make this special arrangement, if it is special, since Earth is in the mix of all this.

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It may all be due to CP violation in neutrinos:

https://www.newscientist.com/article/2240543-neutrinos-may-explain-why-we-dont-live-in-...

"Our leading theories tell us that, in the moments after the big bang, there was an equal amount of matter and antimatter. The two annihilate when they meet, which means the universe should contain energy and no matter. Somehow, a significant chunk of matter avoided this fate, and ultimately turned into stars, planets and people. Quite why is a long-standing mystery. (my bold)

"But there are clues. Theory tells us that for each type of matter particle there is an antimatter particle that is an exact match except for having the opposite electrical charge. This concept is called CP symmetry. For some matter to have survived the early universe, there must be some other differences between matter and antimatter – these differences are called CP violation.

"CP violation has been measured in some particles, called quarks, but the level isn’t nearly enough to explain the observed imbalance between matter and antimatter. Now, the Tokai to Kamioka (T2K) collaboration has observed hints that CP violation in neutrinos may be able to make up the difference.

"There are three types, or flavours, of neutrinos: electron, muon and tau. As they travel, neutrinos can switch, or oscillate, among these flavours. The T2K experiment in Japan is designed to measure those oscillations by shooting beams of neutrinos or antineutrinos 295 kilometres through the ground and measuring which flavours are there at the beginning and end of the neutrinos’ journey.

***

"Over the past decade, hints of CP violation in T2K data have been slowly building. “The picture that’s in this paper has been emerging gradually,” says Edward Blucher at the University of Chicago. “This has been like a photographic image that’s been getting sharper and sharper over the last decade.”

"We aren’t yet entirely sure that neutrino oscillations violate CP symmetry, though. “The most probable solution is maximal CP violation, but we haven’t disproved all possible ways to get no CP violation,” says Sanchez. In particle physics, researchers usually require 99.99994 per cent confidence before they declare a finding certain.

"And even if the oscillations do produce the maximum possible amount of CP violation, we’re not sure whether that would be enough to completely explain the imbalance between matter and antimatter.

“'Studying the universe is like building a building, so you have to understand and measure every brick,” says Sanchez. “If, in the end, this is not enough to produce matter-antimatter asymmetry, fine – it is still an important brick.”

"The amount of CP violation will probably be found by neutrino experiments that are being worked on now, like the T2HK experiment in Japan or DUNE in the US.

“'This is much more of a marathon kind of effort than a sprint, and this work represents an important first step,” says Blucher. “If these hints of large CP violation turn out to be correct, there’s a good chance that the next generation of experiments will confirm it relatively soon, within the next 15 years or so.'”

Comment: Finding out exactly how the universe evolved is long tedious work. God is a sneaky fellow who works in mysterious ways. But He gave us the brain to do it. All of the strange machinations must be required to achieve this result. Note my bold: it is possible to be all energy without matter.

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The neutrino experiments must go on; an editorial comment:

https://www.nature.com/articles/d41586-020-01022-3?WT.ec_id=NATURE-20200416&utm_sou...

"Using these data, the T2K collaboration measured the probability that a neutrino would oscillate between different physical properties that physicists call ‘flavours’ during its journey. The team then ran the same experiment with antineutrinos, and compared the numbers. If matter and antimatter are perfectly symmetrical, the probabilities should be the same.

"The results, however, suggest they are not. T2K detected a higher probability that neutrinos would change flavour during their 300-km journey — and a correspondingly lower probability for antineutrinos — than would be expected if they behaved identically.

"Such a finding, if it can be confirmed, lends weight to Sakharov’s explanation from 1967 that matter and antimatter have different properties. But there’s a caveat: the current finding does not satisfy the required level of confidence — known as 5-sigma (5σ) — that particle physicists would typically demand to consider the result a discovery. The present T2K results are at a 3σ level of statistical significance — and this drops to 2σ if matter–antimatter symmetry is to be ruled out entirely.

"Even so, it’s important to publish such fundamental work as it progresses. Experiments in particle physics can take decades to be planned and built, so results that are not yet at the 5σ significance have a crucial role in informing the community’s decisions on future investments.

"The researchers could have waited longer. But even if they had, the T2K experiment is unlikely to have provided the additional data required to cross the 5σ finishing line. To get to 5σ, physicists will need results from the next generation of neutrino detectors.

"Fortunately, there are three such detectors due to come on stream: Hyper-Kamiokande, located near Super-Kamiokande, expected to start in 2027; DUNE in the United States, due to start in 2025; and JUNO in China, which aims to be the first of the three to go live, in 2022.

"Time will tell if these preliminary observations hold. But at a time when big investments in high-energy physics are coming under increased scrutiny, this result reinforces the importance of continuing to search for answers to some of the Universe’s deepest mysteries."

Comment: Deep mysteries take lots of time to solve. An example of five sigma is: .00006 odds it correct. God works in very mysterious or necessary ways.

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The answer is we do not know. Sabine Hossenfelder has a different view of the entire issue:

http://backreaction.blogspot.com/2020/04/no-physicists-have-not-explained-why.html

"every couple of months I have to endure yet another media blast about physicists who may have solved a problem that does not exist in the first place.

"The most recent installation of this phenomenon are loads of articles about the recent T2K results that hint at CP violation in the neutrino sector. Yes, this is an interesting result and deserves to be written about. The problem is not the result itself, the problem is scientists and science writers who try to make this result more important than it is.

"You can see for yourself what the problem is by reading the reports in the media. Not a single one of them explains why anyone should think there ever were equal amounts of matter and anti-matter to begin with. Leah Crane, for example, writes for New Scientist: “Our leading theories tell us that, in the moments after the big bang, there was an equal amount of matter and antimatter.”

"But, no, they do not. They cannot. You don’t even need to know what these “leading theories” look like in detail, except that, as all current theories in physics, they work by applying differential equations to initial values. Theories of this type can never explain the initial values themselves. It’s not possible. The theories therefore do not tell us there was an equal amount of matter and antimatter. This amount is a postulate. The initial conditions are always assumptions that the theory does not justify.

"Instead, physicists think for purely aesthetic reasons it would have been nicer if there was an equal amount of matter and antimatter in the early universe. Trouble is, this does not agree with observation. So then they cook up theories for how you can start with an equal amount of matter and anti-matter and still end up with a universe like the one we see. You find a good illustration for this in a paper by Steigman and Scherrer with the title “Is The Universal Matter - Antimatter Asymmetry Fine Tuned?” (arXiv:1801.10059) They write:

“'One possibility is that the Universe actually began in an asymmetric state, with more baryons and antibaryons. This is, however, a very unsatisfying explanation. Furthermore, if the Universe underwent a period of inflation (i.e., very rapid expansion followed by reheating), then any preexisting net baryon number would have been erased. A more natural explanation is that the Universe began in an initally [sic] symmetric state, with equal numbers of baryons and antibaryons, and that it evolved later to produce a net baryon asymmetry.'”

Comment: Hossenfelder's point is simple. There is no proof there were equal amounts of matter and antimatter in the beginning. The asymmetry may have been there at the start.

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The moon was hit at that point according to new research, meaning Earth probably was:

https://www.newscientist.com/article/2249457-moon-craters-hint-huge-asteroids-bombarded...

"The moon may have been battered by a massive asteroid storm about 800 million years ago, in which 2 million billion kilograms of rock rained down. These would also have pummelled Earth and could have kickstarted one of the most brutal ice ages in the planet’s history.

"It is difficult to measure the history of Earth’s surface because erosion and the effects of life tend to cover any craters, but we can look to the moon for clues. “It is a witness to the history of the solar system,” says Kentaro Terada at Osaka University in Japan. Any swarm of objects that gets close enough to hit the moon will probably hit Earth as well, so it can give us hints about our planet’s past.

“'The moon’s surface has no erosion, so it preserves the impact history of the Earth-moon system,” says Terada. He and his colleagues used images from Japan’s Selenological and Engineering Explorer (SELENE), a lunar orbiter often known by its nickname Kaguya, to examine craters on the moon.

"They analysed images of 59 craters to determine their ages and found that eight of them, including the huge Copernicus crater, appear to have formed at around the same time – about 800 million years ago. Considering the sizes of the craters, the researchers calculated that about two million billion kilograms of rock probably smashed into the moon at around that time.

"Based on the relative sizes of Earth and the moon and how close they are together, they calculated that if this amount of rock did indeed hit the moon, about 23 times as much probably bombarded Earth from the same cloud of rocky space debris. That is between 30 and 60 times as much mass as the Chicxulub impactor that scientists think killed the dinosaurs hundreds of millions of years later.

***

"Those moments of terror may have plunged Earth into the most intense ice ages the planet has ever experienced during what is known as the Cryogenian period, says Terada. However, so much is still unknown about this colossal asteroid storm that, while we know it marked the face of the moon, we can’t say for sure what its effects on Earth may have been.

“'It seems like things should have been happening on Earth at the same time, so I’m interested to see it tested against geological data,” says Bottke. “This is not the end of the story, it’s the opening shot.'”

Comment: If this is true, obviously the simple life of that era survived and then evolved. Not like the Chixculub event.

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Long large filaments from the Big Bang long ago proposed show some evidence:

https://www.quantamagazine.org/pulsar-data-may-point-to-cosmic-strings-from-the-big-ban...

"Cosmologists think that at the beginning of the universe, all the forces of nature were, for a brief fraction of a second, unified. But as the universe expanded and cooled, this superforce condensed into its familiar parts: gravity, electromagnetism and the strong and weak forces.

"According to some calculations, the cosmos might have cooled so quickly that the fabric of space-time became fractured, creating a network of whisper-thin tubes filled by pure energy that stretch across the breadth of the observable universe.

"This is one possible origin story of cosmic strings.

***

"The new data that might suggest the presence of cosmic strings comes from NANOGrav, a group of astronomers who keep a watchful eye on dozens of spinning dead stars called pulsars.

"Pulsars beam out radio waves from their poles, so that from Earth we see regular flashes each time the beams sweep by our line of sight, like the flashes of a lighthouse. In fact, pulsar blips seem so unnaturally regular that on their discovery in 1967 the first pulsar was named LGM-1 for “little green men.”

"Pulsars are the most precise cosmic timekeepers. So when their blips are distorted, physicists know something is up. In particular, the researchers look for distortions caused by gravitational waves — ripples in space-time that, when they pass through the pulsars, change the blips’ arrival time on Earth. These gravitational waves could come from the thrumming of cosmic strings, collisions of supermassive black holes, or other violent cosmic processes.

***

"The paper is still being peer-reviewed, but the researchers found that something was distorting the blips emitted by all of the pulsars in the same way, and with frequencies that are expected of gravitational waves. It remains possible that this pattern is instead coming from some unknown, common source of noise in the pulsars, or in the clocks that measure the blips’ arrival on Earth."

Comment: Tantalizing findings, not related to the tiny string theory. The universe still contains some amazing secrets. God, as architect, continues to confuse us.

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Which may make up for the 40% missing matter:

https://www.sciencedaily.com/releases/2020/11/201106113858.htm

"Astrophysicists consider that around 40% of the ordinary matter that makes up stars, planets and galaxies remains undetected, concealed in the form of a hot gas in the complexe cosmic web. Today, scientists may have detected, for the first time, this hidden matter through an innovative statistical analysis of 20-year-old data.

***

"Galaxies are distributed throughout the Universe in the form of a complex network of nodes connected by filaments, which are in turn separated by voids. This is known as the cosmic web. The filaments are thought to contain almost all of the ordinary (so-called baryonic) matter of the Universe in the form of a diffuse, hot gas. However, the signal emitted by this diffuse gas is so weak that in reality 40 to 50% of the baryons goes undetected.

***

"In a new study, funded by the ERC ByoPiC project, they present a statistical analysis that reveals, for the first time, the X-ray emission from the hot baryons in filaments. This detection is based on the stacked X-ray signal, in the ROSAT[2] survey data, from approximately 15,000 large-scale cosmic filaments identified in the SDSS[3] galaxy survey. The team made use of the spatial correlation between the position of the filaments and the associated X-ray emission to provide evidence of the presence of hot gas in the cosmic web, and for the first time measure its temperature.

"These findings confirm earlier analyses by the same research team, based on indirect detection of hot gas in the cosmic web through its effect on the cosmic microwave background[4]. This paves the way for more detailed studies,..."

Comment: Bit by bit we are unearthing more the universe's structure.

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New study finds it is much bigger than known before:

https://www.sciencenews.org/article/astronomers-have-found-edge-milky-way-size

"Our galaxy is a whole lot bigger than it looks. New work finds that the Milky Way stretches nearly 2 million light-years across, more than 15 times wider than its luminous spiral disk. The number could lead to a better estimate of how massive the galaxy is and how many other galaxies orbit it.

***

"Now, Alis Deason, an astrophysicist at Durham University in England, and her colleagues have used nearby galaxies to locate the Milky Way’s edge. The precise diameter is 1.9 million light-years, give or take 0.4 million light-years, the team reports February 21 in a paper posted at arXiv.org.

"To put that size into perspective, imagine a map in which the distance between the sun and the Earth is just one inch. If the Milky Way’s heart were at the center of the Earth, the galaxy’s edge would be four times farther away than the moon actually is.

***

"Although dark matter makes up most of the Milky Way’s mass, the simulations reveal that stars should also exist at these far-out distances. “Both have a well-defined edge,” Deason says. “The edge of the stars is very sharp, almost like the stars just stop at a particular radius.”

"In the future, astronomers can refine the location of the Milky Way’s edge by discovering additional small galaxies nearby. Astronomers could also search for individual stars out at the boundary, says Mike Boylan-Kolchin, an astrophysicist at the University of Texas at Austin who was not involved with the study. The farthest such stars will be very dim, but future observations should be able to find them.

:The measurement should also help astronomers tease out other galactic properties. For instance, the larger the Milky Way, the more massive it is — and the more galaxies there should be revolving around it, says Rosemary Wyse, an astronomer at Johns Hopkins University who was not part of the new work. So far, there are about 60 known Milky Way satellites, but astronomers suspect that many more await discovery."

Comment: We are a giant and that may well relate to why we have life. We know the Earth exists well out from the nasty dangerous center. My view is God plans well.

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Now measured:

https://www.quantamagazine.org/physicists-pin-down-nuclear-reaction-from-moments-after-...

"In a secluded laboratory buried under a mountain in Italy, physicists have re-created a nuclear reaction that happened between two and three minutes after the Big Bang.

"Their measurement of the reaction rate, published today in Nature, nails down the most uncertain factor in a sequence of steps known as Big Bang nucleosynthesis that forged the universe’s first atomic nuclei.

***

"Deuterium’s creation was the first step in Big Bang nucleosynthesis, a sequence of nuclear reactions that occurred when the cosmos was a super hot but rapidly cooling soup of protons and neutrons.

***

"The measured rate — which says how quickly deuterium tends to fuse with a proton to form helium-3 across the range of temperatures found in the epoch of primordial nucleosynthesis — landed between the 2016 theoretical prediction and the 1997 measurement. More importantly, when physicists feed this rate into the equations of Big Bang nucleosynthesis, they predict a primordial matter density and a cosmic expansion rate that closely square with observations of the cosmic microwave background 380,000 years later.

“'It essentially tells us that the standard model of cosmology is, so far, quite right,” said Aliotta.

"That in itself squeezes the gap that next-generation models of the cosmos must fit into. Experts say some theories of dark matter could even be ruled out by the results.

***

"On the horizon is the next generation of cosmic microwave background measurements. Meanwhile, with deuterium’s behavior now better understood, uncertainties in other primordial nuclear reactions and elemental abundances become more pressing.

"A longstanding “fly in the Big Bang nucleosynthesis ointment,” according to Fields, is that the matter density calculated from deuterium and the cosmic microwave background predicts that there should be three times more lithium in the universe than we actually observe.

“'There are still lots of unknowns,” said Aliotta. “And what the future will bring is going to be very interesting.'”

Comment: Our understanding of how God made the universe is ongoing and our big brains are doing the job. The Standard Model remains as rigidly correct as Einstein's theories.

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More findings on how it got so big:

https://phys.org/news/2020-11-family-tree-milky-deciphered.html

"Scientists have known for some time that galaxies can grow by the merging of smaller galaxies, but the ancestry of our own Milky Way galaxy has been a long-standing mystery. Now, an international team of astrophysicists has succeeded in reconstructing the first complete family tree of our home galaxy by analyzing the properties of globular clusters orbiting the Milky Way with artificial intelligence.

***

"In the simulations, the researchers were able to relate the ages, chemical compositions, and orbital motions of globular clusters to the properties of the progenitor galaxies in which they formed, more than 10 billion years ago. By applying these insights to groups of globular clusters in the Milky Way, they could not only determine how many stars these progenitor galaxies contained, but also when they merged into the Milky Way.

"'The main challenge of connecting the properties of globular clusters to the merger history of their host galaxy has always been that galaxy assembly is an extremely messy process, during which the orbits of the globular clusters are completely reshuffled," Kruijssen explains.

***

"By applying the neural network to these groups of globular clusters, the researchers could not only predict the stellar masses and merger times of the progenitor galaxies to high precision, but it also revealed a previously unknown collision between the Milky Way and an enigmatic galaxy, which the researchers named "Kraken."

"The collision with Kraken must have been the most significant merger the Milky Way ever experienced," Kruijssen adds. "Before, it was thought that a collision with the Gaia-Enceladus-Sausage galaxy, which took place some 9 billion years ago, was the biggest collision event. However, the merger with Kraken took place 11 billion years ago, when the Milky Way was four times less massive. As a result, the collision with Kraken must have truly transformed what the Milky Way looked like at the time."

"Taken together, these findings allowed the team of researchers to reconstruct the first complete merger tree of our Galaxy. Over the course of its history, the Milky Way cannibalized about five galaxies with more than 100 million stars, and about fifteen with at least 10 million stars. The most massive progenitor galaxies collided with the Milky Way between 6 and 11 billion years ago."

Comment: The Milky Way was carefully designed, as noted before, to create a galaxy big enough to hide out the Earth in a safe spot for life to survive.

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DAVID: The Milky Way was carefully designed, as noted before, to create a galaxy big enough to hide out the Earth in a safe spot for life to survive.

So who do you think designed all the terrible dangers that would have threatened the Earth?

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DAVID: The Milky Way was carefully designed, as noted before, to create a galaxy big enough to hide out the Earth in a safe spot for life to survive.

dhw: So who do you think designed all the terrible dangers that would have threatened the Earth?

God!!! The processes that make galaxies and stars and solar systems are all inherently dangerous to life with all the radioactivity required as part of the processes. Like the way biochemistry of life works resulting in molecular errors, God has to create the only way He can. One has to recognize God's knowledge of possible designs.

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They MUST exist, but we do not know what they are:

http://cosmos.nautil.us/short/135/dark-matter-is-our-friend?mc_cid=f7a1ff6950&mc_ei...

"Dark matter is our friend. Dark matter creates the galaxies and all the other large structures that are held together by gravity. Without dark matter the universe would just be a thin soup of ordinary matter. There would be no galaxies, no stars, no heavy elements, no rocky planets, and no life. So we owe a tremendous debt to dark matter.

***

"For various theoretical reasons, the most natural value of the total density of the universe is a quantity called critical density, and observations indicated that ordinary matter plus dark matter account for less than that. In 1991 my collaborators and I considered the possibility that the remainder was a form of energy that Einstein called the cosmological constant or, more generally, what we know today as dark energy. We worked out how a cosmological constant would affect the formation of gravitationally bound structures such as galaxies and galaxy clusters.

***

"These models fit the COBE data, but the real confirmation did not come until 1998, when two competing teams of astronomers independently found that the expansion of the universe has been speeding up—the telltale effect of the cosmological constant. The clincher has been measurements by two follow-ups to COBE, NASA’s WMAP satellite and the European Space Agency’s Planck satellite, which confirm the predictions of the double-dark theory with fantastic precision.

"Even those of us who helped to create the model are amazed it works so well. Some astrophysicists have worried that its predictions might disagree with observations of certain regions, such as the smallest galaxies and the cores of galaxies or galaxy clusters. But improved simulations have refined the predictions and appear to have resolved these issues. We now at last have a picture of the evolution and structure of the universe that might actually be true.

"But the model does not tell us what dark matter and dark energy are; it simply captures their large-scale effects. We still have no direct evidence for either supersymmetry or WIMPs. Alternative explanations of dark matter have been proposed, but there is no convincing evidence for them, either.

***

"Physicists and astronomers are working hard to identify dark matter and dark energy, and when we do, it could well represent a revolution in our understanding of the fundamental nature of the universe greater than the one that gave us the Standard Model.

"The ongoing cosmological revolution has implications so profound and far-reaching that it cannot help but alter how we humans view our place in the universe. We will need to seek new modes of understanding. Although no one ever imagined the bizarre universe that science is discovering, we can draw on the entire human experience to try to make sense of it.

***

"Our goal has been to explain how we humans arose from and fit into the modern universe. We seek to connect ideas such as the double-dark universe with other aspects of science and philosophy, including ancient wisdom traditions. For example, Native American and other traditional cultures hold that humans arose from the earth and bear close relationships with other animals. That is consonant with modern science.

"The brief moment of cosmic inflation that started our expanding universe has analogues in ancient Egyptian creation myths and in the ideas of Kabbalah, medieval Jewish mysticism.

"The first three parts of the Kabbalistic tree of life are Keter, Hokhmah, and Binah. Like Keter, eternal inflation is the infinite source of all possibilities; like Hokhmah, cosmic inflation is the exit from eternity that prepares the blueprint for the future universe; like Binah, the expanding universe has turned the primal plan into spacetime and galaxies. Binah was seen as female in Kabbalah. It is a bit startling to identify the expanding universe with a womb, yet there is something reassuring about positing motherly understanding as a cosmic quality. Hokhmah was seen as male, while Keter was beyond gender, nicely balancing things out.

"The idea that any aspect of the universe is either male or female is, of course, not to be taken literally. But there is no reason that people outside science should process the ideas of modern cosmology in the same way that scientists have. Science is discovering a remarkable unity and intricacy to the natural world, and mythological concepts can perhaps help us experience these connections."

Comment: Conundrums wrapped in mysteries. We know of dark matter and dark energy by their effects. God creates in mysterious ways and Jewish mystics in the Kabbalah had a clue!

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We receive them, but what are they caused by?:

https://www.newscientist.com/article/2259924-repeated-radio-bursts-from-nearby-star-sug...

"Kirsten and his colleagues say they have detected two further weak bursts from SGR 1935+2154, each lasting just a millisecond and separated by 1.4 seconds. The weaker bursts were detected in May by the Westerbork Synthesis Radio Telescope in the Netherlands. Both of the May bursts were about 10,000 times weaker than April’s initial FRB.

***

“'The exciting thing is these bursts bridge the gap between single pulses that are fairly weak and FRB-like bursts,” says Chris Bochenek at the California Institute of Technology, who led part of the initial discovery of the FRB source in April. “We [now] know there are processes happening all along this spectrum of energies.”

"An FRB is loosely defined as any radio burst that is bright enough to be seen from another galaxy. However, it is possible that these weaker bursts – only visible to astronomers because their source is relatively near to Earth – could be produced by the same mechanism as FRBs. They may even be FRBs, albeit weaker ones.

"At the moment, the mechanism of FRB production isn’t understood. “There are many theories,” says Daniele Michilli, a member of the CHIME team who is based at McGill University in Montreal, Canada. “The first class is where the emission comes from the magnetosphere of the star. A second class of theories is where there is like a fireball that ignites emission from a plasma cloud farther away from the star.”

"With more observations of magnetars like SGR 1935+2154, it may be possible to see more evidence of different ranges of burst activity. Factors such as the age of the star might play a role, say Kirsten and his colleagues, with younger magnetars producing brighter FRBs. Other cosmic objects, such as binary stars, could also be producing FRBs alongside magnetars.

“'This paper opens up new questions,” says Bochenek. “Is this like FRB emission? Where does one [emission] stop and the other one start? And what is an FRB?'”

Comment: Here we go again. The complexity of the activities of the universe grow and we don't know much about this one. All I can assume is God needed to create this function

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QUOTE: "Over the course of its history, the Milky Way cannibalized about five galaxies with more than 100 million stars, and about fifteen with at least 10 million stars. The most massive progenitor galaxies collided with the Milky Way between 6 and 11 billion years ago."

DAVID: The Milky Way was carefully designed, as noted before, to create a galaxy big enough to hide out the Earth in a safe spot for life to survive.

dhw: So who do you think designed all the terrible dangers that would have threatened the Earth?

DAVID: God!!! The processes that make galaxies and stars and solar systems are all inherently dangerous to life with all the radioactivity required as part of the processes. Like the way biochemistry of life works resulting in molecular errors, God has to create the only way He can. One has to recognize God's knowledge of possible designs.

Once again, as with the evolution of life, my mind boggles at the thought that your God had to produce these vast numbers of stars/species in order to produce one planet/species. And how many millions of these stars and life forms disappeared before your God was able to directly design the only life form (plus food supply) he wanted to design? I can’t help wondering why this was the “only way” an all-powerful God could possibly create a single species. What is described here is, of course, history. But I can well understand why, given the fact that our galaxy is thought to be just one of between 100 and 200 thousand million galaxies, some folk reckon that chance is just as likely an explanation of life as a single, designing, sourceless mind that can fiddle with billions of stars as well as provide single cells with programmes for the whole of life's evolution. Can’t you?

Under “killer asteroids”
QUOTE: "As news of a possible threat from Apophis arises, others have pointed out that the human race has made strides in protecting the planet from asteroid strikes. NASA's DART mission, for example, scheduled for 2022, will involve sending a spacecraft to an asteroid called Didymos and using it to alter the path of Dimorphos, one of its moons. [..] (David's bold)

DAVID: We've made real advances since we started to worry about asteroids striking the Earth, as shown in my bold. In the theodicy discussion this evil or danger was not noted but it is another issue for that topic. My only answer it that the solar system may have had to have those a steroid bodies present in its formation. At least we know different ways of moving them from their orbit, if dangerous.

You’re right: the massive scale of the universe, and the seemingly random comings and goings and dangers on a local, planetary and universal scale are an issue not only for theodicy but for the whole idea of a single mind consciously designing every galaxy and every earthly twiddly bit “as part of the goal of evolving [= directly designing] humans.” And your only answer is that it must have been the only way your God could do it.

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QUOTE: "Over the course of its history, the Milky Way cannibalized about five galaxies with more than 100 million stars, and about fifteen with at least 10 million stars. The most massive progenitor galaxies collided with the Milky Way between 6 and 11 billion years ago."

DAVID: The Milky Way was carefully designed, as noted before, to create a galaxy big enough to hide out the Earth in a safe spot for life to survive.

dhw: So who do you think designed all the terrible dangers that would have threatened the Earth?

DAVID: God!!! The processes that make galaxies and stars and solar systems are all inherently dangerous to life with all the radioactivity required as part of the processes. Like the way biochemistry of life works resulting in molecular errors, God has to create the only way He can. One has to recognize God's knowledge of possible designs.

dhw" Once again, as with the evolution of life, my mind boggles at the thought that your God had to produce these vast numbers of stars/species in order to produce one planet/species. And how many millions of these stars and life forms disappeared before your God was able to directly design the only life form (plus food supply) he wanted to design?

Are you assuming there were living species before humans?

dhw: I can’t help wondering why this was the “only way” an all-powerful God could possibly create a single species. What is described here is, of course, history. But I can well understand why, given the fact that our galaxy is thought to be just one of between 100 and 200 thousand million galaxies, some folk reckon that chance is just as likely an explanation of life as a single, designing, sourceless mind that can fiddle with billions of stars as well as provide single cells with programmes for the whole of life's evolution. Can’t you?

No, logic tells me the extraordinary basis of reality in the complexity of quantum mechanics, and the exquisite engineering of cellular biology requires just such a mind as the one you doubt .

Under “killer asteroids”
QUOTE: "As news of a possible threat from Apophis arises, others have pointed out that the human race has made strides in protecting the planet from asteroid strikes. NASA's DART mission, for example, scheduled for 2022, will involve sending a spacecraft to an asteroid called Didymos and using it to alter the path of Dimorphos, one of its moons. [..] (David's bold)

DAVID: We've made real advances since we started to worry about asteroids striking the Earth, as shown in my bold. In the theodicy discussion this evil or danger was not noted but it is another issue for that topic. My only answer it that the solar system may have had to have those a steroid bodies present in its formation. At least we know different ways of moving them from their orbit, if dangerous.

dhw: You’re right: the massive scale of the universe, and the seemingly random comings and goings and dangers on a local, planetary and universal scale are an issue not only for theodicy but for the whole idea of a single mind consciously designing every galaxy and every earthly twiddly bit “as part of the goal of evolving [= directly designing] humans.” And your only answer is that it must have been the only way your God could do it.

Again you have reverted to faulting God's methods. Analysis through research of what He created will offer explanations and we are given the brains by Him to find them.

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Theories on how the Milky Way formed are set to be rewritten following discoveries about the behavior of some of its oldest stars:

https://phys.org/news/2020-11-orbits-ancient-stars-prompt-rethink.html

"An investigation into the orbits of the Galaxy's metal-poor stars—assumed to be among the most ancient in existence—has found that some of them travel in previously unpredicted patterns.

"'Metal-poor stars—containing less than one-thousandth the amount of iron found in the Sun—are some of the rarest objects in the galaxy," said Professor Gary Da Costa.

***

"'We've studied 475 of them and found that about 11 percent orbit in the almost flat plane that is the Milky Way's disc.

"'They follow an almost circular path—very much like the Sun. That was unexpected, so astronomers are going to have to rethink some of our basic ideas."

"Previous studies had shown that metal-poor stars were almost exclusively confined to the Galaxy's halo and bulge, but this study revealed a significant number orbiting the disk itself.

"The Sun also orbits within the disk, which is why it manifests as the comparatively thin, ribbon-like structure easily visible from Earth in the night sky. In effect, we are seeing it edge-on.

***

"This discovery is not consistent with the previous Galaxy formation scenario and adds a new piece to the puzzle that is the Milky Way. Their orbits are very much like that of the Sun, even though they contain just a tiny fraction of its iron. Understanding why they move in the way that they do will likely prompt a significant reassessment of how the Milky Way developed over many billions of years."

***

"As expected, many of the stars had largely spherical orbits, clustering around the Galaxy's "stellar halo"—a structure thought to be at least 10 billion years old.

"Others had uneven and "wobbly" paths assumed to be the result of two cataclysmic collisions with smaller galaxies that occurred in the distant past—creating structures known as the Gaia Sausage and the Gaia Sequoia.

"Some stars were orbiting retrograde—effectively going the wrong way around the Galaxy—and a few, about five percent, appeared to be in the process of leaving the Milky Way altogether.

"And then there were the remaining 50 or so, with orbits that aligned with the Galaxy's disk.

"'I think this work is full of important and new results, but if I had to choose one that would be the discovery of this population of extremely metal-poor disk stars," said Cordoni."

Comment: We know our galaxy seems very unique. These new findings add to the mystery of its formation. but the result is obvious, the Earth is very protected.

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Just recently discovered:

https://phys.org/news/2020-12-milky-primordial-history-fossil.html

"Just as archaeologists dig hoping to find traces of the past, an international group of astrophysicists managed to get into the thick cloud of dust around the center of the Milky Way (also known as the bulge) discovering primordial clumps of gas and stars never before seen. They named this new class of stellar system 'Bulge Fossil Fragments.'

***

"Researchers found out about this new class while analyzing Liller 1. The latter is a stellar system in the Milky Way bulge that for more than 40 years has been classified as a "globular cluster," i.e. a system composed of millions of same-aged stars (the Milky Way has at least 150 globular clusters). However, researchers observed Liller 1 closely and found out that its real identity is actually more fascinating than so far believed. Indeed, Liller 1 is a fossil fragment of one of the giant stellar clumps that, approximately 12 billion years ago, merged to form the central region (bulge) of the Milky Way.

"'Our results clearly show that Liller 1 is not a globular cluster, but a much more complex object," says Professor Francesco Ferraro, first author and coordinator of the study. "It is a stellar relic, a fossil finding that contains the history of the Milky Way formation."

"The existence of "cosmic findings" had already been suggested when researchers discovered a similar object, Terzan 5, some years ago. Terzan 5 looked like a globular cluster within our galaxy bulge, but, at a closer analysis, its features were not consistent with those of other globular clusters.

"However, an isolated case is just an intriguing anomaly. This is why Liller 1 is so important. Terzan 5 and Liller 1 shared features confirm the existence of a new class of stellar systems unidentified until today.

"What are the features of the Bulge Fossil Fragments? These objects are disguised as globular clusters, but are fundamentally different, if one looks at the age of the stars composing them. Two stellar populations are in these systems: one is as old as the Milky Way—it formed 12 billion years ago—and the other one is much younger. On the one hand, this shows that these stellar systems appeared during the Milky Way early stages of formation; on the other hand, it demonstrates that they are able to engender multiple events of stellar generation.

***

"'The history of the Milky Way is written in these fossil remains. The latter are tokens of an age during which the Universe was very young, just 1 billion years old," concludes professor Ferraro. "Now we need to go deeper. Thanks to the discovery of these fossil remains we can start reading the history of the Milky Way and maybe re-define our knowledge about the formation of the bulge.'"

Comment: Note the age of the Milky Way at 12 billion years, which is just 1.78 billion years from the estimated Big Bang. As I see God in charge of evolving the universe, I see Him here starting early to set up the proper galaxy to contain a special planet for life.

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dhw: "Once again, as with the evolution of life, my mind boggles at the thought that your God had to produce these vast numbers of stars/species in order to produce one planet/species. And how many millions of these stars and life forms disappeared before your God was able to directly design the only life form (plus food supply) he wanted to design?

DAVID: Are you assuming there were living species before humans?

I have no idea. I am merely questioning your assumption that your God’s purpose in designing all these billions of stars and all these millions of life forms was to design H. sapiens.

dhw: I can’t help wondering why this was the “only way” an all-powerful God could possibly create a single species. What is described here is, of course, history. But I can well understand why, given the fact that our galaxy is thought to be just one of between 100 and 200 thousand million galaxies, some folk reckon that chance is just as likely an explanation of life as a single, designing, sourceless mind that can fiddle with billions of stars as well as provide single cells with programmes for the whole of life's evolution. Can’t you?

DAVID: No, logic tells me the extraordinary basis of reality in the complexity of quantum mechanics, and the exquisite engineering of cellular biology requires just such a mind as the one you doubt.

Quantum mechanics remains a mystery, and I accept the logic of the design argument. How does that explain the need for your God to create between 100 and 200 thousand million galaxies, and millions of life forms with no connection to humans, in order to produce a single species and its food supply?

dhw: […] your only answer is that it must have been the only way your God could do it.

DAVID: Again you have reverted to faulting God's methods. Analysis through research of what He created will offer explanations and we are given the brains by Him to find them.

There are two levels here: 1) I regard the sheer enormity and impersonality of the ever changing universe as a major hindrance to belief in a sourceless mind that created and “controls” it. This is a counter to the logic of the design theory. Hence my agnosticism. 2) If God exists, I do not fault his methods. I question the accuracy of your interpretation of his purpose and his methods. You know this because I have repeated it a hundred times.

DAVID (under “far out cosmology”: We know our galaxy seems very unique. These new findings add to the mystery of its formation. but the result is obvious, the Earth is very protected.

Microcosm/macrocosm. You don’t know why your God designed bad bugs, and you don’t know why he designed the forces that threaten our planet. But you believe that “analysis…will offer explanations.” This puts you very much on a par with Dawkins: “If there is something that appears to lie beyond the natural world…..we hope eventually to understand it and embrace it within the natural.” Instead of predicting/hoping that your totally opposite beliefs will one day be confirmed, perhaps both of you should face the fact that neither of you has one jot of scientific support for them.

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DAVID: Are you assuming there were living species before humans?

dhw: I have no idea. I am merely questioning your assumption that your God’s purpose in designing all these billions of stars and all these millions of life forms was to design H. sapiens.

Why question the fact that evolution lead to humans?

DAVID: logic tells me the extraordinary basis of reality in the complexity of quantum mechanics, and the exquisite engineering of cellular biology requires just such a mind as the one you doubt.

dhw:m Quantum mechanics remains a mystery, and I accept the logic of the design argument. How does that explain the need for your God to create between 100 and 200 thousand million galaxies, and millions of life forms with no connection to humans, in order to produce a single species and its food supply?

Previous life forms evolved to produce humans. The rest is all history produced by God.

dhw: […] your only answer is that it must have been the only way your God could do it.

DAVID: Again you have reverted to faulting God's methods. Analysis through research of what He created will offer explanations and we are given the brains by Him to find them.

dhw: There are two levels here: 1) I regard the sheer enormity and impersonality of the ever changing universe as a major hindrance to belief in a sourceless mind that created and “controls” it. This is a counter to the logic of the design theory. Hence my agnosticism.

It is not counter to design theory: why a Big Bang, followed by amorphous plasma, which then produced matter particles? I don't accept chance. Just because the universe confuses you, don't assume chance arrival of it as we see it now. .

2) If God exists, I do not fault his methods. I question the accuracy of your interpretation of his purpose and his methods. You know this because I have repeated it a hundred times.

It is simple to accept the history as His m ethod.

DAVID (under “far out cosmology”: We know our galaxy seems very unique. These new findings add to the mystery of its formation. but the result is obvious, the Earth is very protected.

dhw: Microcosm/macrocosm. You don’t know why your God designed bad bugs, and you don’t know why he designed the forces that threaten our planet. But you believe that “analysis…will offer explanations.” This puts you very much on a par with Dawkins: “If there is something that appears to lie beyond the natural world…..we hope eventually to understand it and embrace it within the natural.” Instead of predicting/hoping that your totally opposite beliefs will one day be confirmed, perhaps both of you should face the fact that neither of you has one jot of scientific support for them.

Well said as an agnostic.

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Two different reactions seen:

https://www.nature.com/articles/d41586-020-03238-9?utm_source=Nature+Briefing&utm_c...

"...the Borexino Collaboration1 reports results that blast past a milestone in neutrino physics. They have detected solar neutrinos produced by a cycle of nuclear-fusion reactions known as the carbon–nitrogen–oxygen (CNO) cycle. Measurements of these neutrinos have the potential to resolve uncertainties about the composition of the solar core, and offer crucial insights into the formation of heavy stars.

***

"Fusion reactions in the Sun produce an astonishing number of neutrinos: roughly 100 billion solar neutrinos pass through each of your thumbnails every second. Because of the weakness of their interactions, they are barely deterred from their path even when they have to pass through the entire body of the Earth: cutting-edge experiments5 (see also go.nature.com/36sktyj) have struggled to observe a difference in the measured neutrino flux between daytime and night-time, owing to the vanishingly small scale of this effect.

***

"The Sun is powered by fusion reactions that occur in its core: in the intense heat of this highly pressurized environment, protons fuse together to form helium. This occurs in two distinct cycles of nuclear reactions. The first is called the proton–proton chain (or pp chain), and dominates energy production in stars the size of our Sun. The second is the CNO cycle, which accounts for roughly 1% of solar power, but dominates energy production in heavier stars.

***

"The Borexino Collaboration now reports another groundbreaking achievement from its experiment: the first detection of neutrinos from the CNO cycle. This result is a huge leap forward, offering the chance to resolve the mystery of the elemental composition of the Sun’s core. In astrophysics, any element heavier than helium is termed a metal. The exact metal content (the metallicity) of a star’s core affects the rate of the CNO cycle. This, in turn, influences the temperature and density profile — and thus the evolution — of the star, as well as the opacity of its outer layers.

***

"The Borexino experiment detects light produced when solar neutrinos scatter off electrons in a large vat of liquid scintillator — a medium that produces light in response to the passage of charged particles. A precise measurement of the energy and time profile of the detected light allows the scintillation caused by solar neutrinos to be differentiated from light resulting from other sources, such as radio-active contamination in the scintillator itself and in surrounding detector components."

Comment: Everything is so complex it takes many years of experimental refinement to get reliable results.

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The galaxy is against a race in time; can it make enough stars to stay alive:

https://phys.org/news/2020-11-galaxy-survives-black-hole-feastfor.html

"Black holes are thought to gobble up so much surrounding material that they put an end to the life of their host galaxy. In that process they create a highly energetic object called a quasar which was previously thought to halt star birth. Now researchers have found a galaxy that is surviving the ravenous forces of a quasar by continuing to birth new stars –about 100 Sun-sized stars a year.

***

"'This shows us that the growth of active black holes doesn't stop star birth instantaneously, which goes against all the current scientific predictions," said Allison Kirkpatrick, assistant professor at the University of Kansas in Lawrence Kansas and co-author on the study. "It's causing us to re-think our theories on how galaxies evolve."

"SOFIA, a joint project of NASA and the German Aerospace Center, DLR, studied an extremely distant galaxy, located more than 5.25 billion light years away called CQ4479. At its core is a special type of quasar that was recently discovered by Kirkpatrick called a "cold quasar." In this kind of quasar, the active black hole is still feasting on material from its host galaxy, but the quasar's intense energy has not ravaged all of the cold gas, so stars can keep forming and the galaxy lives on. This is the first time researchers have a detailed look at a cold quasar, directly measuring the black hole's growth, star birth rate, and how much cold gas remains to fuel the galaxy.

"'We were surprised to see another oddball galaxy that defies current theories," said Kevin Cooke, postdoctoral researcher at the University of Kansas in Lawrence, Kansas, and lead author of this study. "If this tandem growth continues both the black hole and the stars surrounding it would triple in size before the galaxy reaches the end of its life."

"As one of the brightest and most distant objects in the universe, quasars, or "quasi-stellar radio sources," are notoriously difficult to observe, because they often outshine everything around them. They form when an especially active black hole consumes huge amounts of material from its surrounding galaxy, creating strong gravitational forces. As more and more material spins faster and faster toward the center of the black hole, the material heats up and glows brightly. A quasar produces so much energy that it often outshines everything around it, blinding attempts to observe its host galaxy. Current theories predict that this energy heats up or expels the cold gas needed to create stars, stopping star birth and driving a lethal blow to a galaxy's growth. But SOFIA reveals, that there is a relatively short period when galaxy's star birth can continue while the black hole's feast goes on powering the quasar's powerful forces.

***

"The short window of joint black hole and star growth represents an early phase in the death of a galaxy, wherein the galaxy has not yet succumbed to the devasting effects of the quasar. Continued research with SOFIA is needed to learn if many other galaxies go through a similar stage with joint black hole and star growth before ultimately reaching the end of life."

Comment: This may explain why we/the Milky Way is so large. We have a giant black hole and still make some stars.

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We are closer to the center and moving faster than previously thought:

https://phys.org/news/2020-11-earth-faster-closer-black-hole.html

"Earth just got 7 km/s faster and about 2000 light-years closer to the supermassive black hole in the center of the Milky Way Galaxy. But don't worry, this doesn't mean that our planet is plunging towards the black hole. Instead the changes are results of a better model of the Milky Way Galaxy based on new observation data, including a catalog of objects observed over the course of more than 15 years by the Japanese radio astronomy project VERA.

"VERA (VLBI Exploration of Radio Astrometry, by the way "VLBI" stands for Very Long Baseline Interferometry) started in 2000 to map three-dimensional velocity and spatial structures in the Milky Way. VERA uses a technique known as interferometry to combine data from radio telescopes scattered across the Japanese archipelago in order to achieve the same resolution as a 2300 km diameter telescope would have. Measurement accuracy achieved with this resolution, 10 micro-arcseconds, is sharp enough in theory to resolve a United States penny placed on the surface of the Moon.

***

"Based on the VERA Astrometry Catalog and recent observations by other groups, astronomers constructed a position and velocity map. From this map they calculated the center of the Galaxy, the point that everything revolves around. The map suggests that the center of the Galaxy, and the supermassive black hole which resides there, is located 25800 light-years from Earth. This is closer than the official value of 27700 light-years adopted by the International Astronomical Union in 1985. The velocity component of the map indicates that Earth is traveling at 227 km/s as it orbits around the Galactic Center. This is faster than the official value of 220 km/s."

Comment: Even with the changes we are very safe.

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It appears everywhere in measurements defining the universe and is roughly 1/137 but it now extended several more decimal points:

https://www.quantamagazine.org/physicists-measure-the-magic-fine-structure-constant-202...

"The fine-structure constant, by contrast, has no dimensions or units. It’s a pure number that shapes the universe to an astonishing degree — “a magic number that comes to us with no understanding,” as Richard Feynman described it. Paul Dirac considered the origin of the number “the most fundamental unsolved problem of physics.”

"Numerically, the fine-structure constant, denoted by the Greek letter α (alpha), comes very close to the ratio 1/137. It commonly appears in formulas governing light and matter. “It’s like in architecture, there’s the golden ratio,” said Eric Cornell, a Nobel Prize-winning physicist at the University of Colorado, Boulder and the National Institute of Standards and Technology. “In the physics of low-energy matter — atoms, molecules, chemistry, biology — there’s always a ratio” of bigger things to smaller things, he said. “Those ratios tend to be powers of the fine-structure constant.”

"The constant is everywhere because it characterizes the strength of the electromagnetic force affecting charged particles such as electrons and protons. “In our everyday world, everything is either gravity or electromagnetism. And that’s why alpha is so important,” said Holger Müller, a physicist at the University of California, Berkeley. Because 1/137 is small, electromagnetism is weak; as a consequence, charged particles form airy atoms whose electrons orbit at a distance and easily hop away, enabling chemical bonds. On the other hand, the constant is also just big enough: Physicists have argued that if it were something like 1/138, stars would not be able to create carbon, and life as we know it wouldn’t exist. (my bold)

***

"Today, in a new paper in the journal Nature, a team of four physicists led by Saïda Guellati-Khélifa at the Kastler Brossel Laboratory in Paris reported the most precise measurement yet of the fine-structure constant. The team measured the constant’s value to the 11th decimal place, reporting that α = 1/137.03599920611. (The last two digits are uncertain.)

"With a margin of error of just 81 parts per trillion, the new measurement is nearly three times more precise than the previous best measurement in 2018 by Müller’s group at Berkeley, the main competition. (Guellati-Khélifa made the most precise measurement before Müller’s in 2011.) Müller said of his rival’s new measurement of alpha, “A factor of three is a big deal. Let’s not be shy about calling this a big accomplishment.”

***

"Though the two measurements differ, they closely match the value of alpha inferred from precise measurements of the electron’s g-factor, a constant related to its magnetic moment, or the torque that the electron experiences in a magnetic field. “You can connect the fine-structure constant to the g-factor with a hell of a lot of math,” said Cornell. “If there are any physical effects missing from the equations [of the Standard Model], we would be getting the answer wrong.”

"Instead, the measurements match beautifully, largely ruling out some proposals for new particles. The agreement between the best g-factor measurements and Müller’s 2018 measurement was hailed as the Standard Model’s greatest triumph. Guellati-Khélifa’s new result is an even better match. “It’s the most precise agreement between theory and experiment,” she said."

Comment: Just more confirmation of the mathematics supporting the standard model. God's math is open for study by us humans. Note in bold the fine-tuning comment.

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A book review of time and cosmological entropy:

https://science.sciencemag.org/content/370/6522/1280?utm_campaign=toc_sci-mag_2020-12-1...

"...are we headed toward the ultimate mundanity of equilibrium in a so-called heat death? In The Janus Point, Julian Barbour takes on this and other fundamental questions, offering the reader a new perspective—illustrated with lucid examples and poetically constructed prose—on how the Universe started (or more precisely, how it did not start) and where it may be headed.

"Barbour argues that there is no beginning of time. The Big Bang, he maintains, was just a very special configuration of the Universe's fundamental building blocks, a shape he calls the Janus point. As we move away from this point, the shape changes, marking the passage of time. The “future,” he argues, lies in both directions, hence the reference to Janus, the two-faced Roman god of beginnings and transitions.

***

"One of the main thrusts of Barbour's proposal is an attempt to reconcile cosmological evolution with the second law of thermodynamics and an arrow of time. As a reminder, the second law is the one that tells us that systems tend toward increasing entropy, sometimes colloquially referred to as disorder. In a closed system, if we begin with order (low entropy), then disorder will grow until the entropy reaches a maximum. The change in entropy can be used to define past (low entropy) and future (high entropy).

"When applied to the Universe, the second law of thermodynamics evokes a number of questions. How did the Universe come to be in a state of low entropy, for example? Barbour's answer to this is the Janus point. In the three-body problem, the Janus point (i.e., a total collision) is an inevitability so long as the total angular momentum vanishes. Recall that angular momentum is among the sacred conserved quantities in classical mechanics, so vanishing at one time implies vanishing for all times. Barbour argues by analogy that the Universe, similarly restricted, must have a Janus point too. If true, the seemingly special configuration at the Janus point is not so special at all but in fact required by a conservation law.

"So, what happens when entropy reaches a maximum? Barbour dodges this question by arguing that entropy is not the right factor to consider and that we should instead look to complexity. With time, he argues, the building blocks of the Universe can arrange themselves into increasingly complex structures.

"Barbour does not buy the argument that the Universe is akin to a closed system whose entropy can reach a maximum and instead takes the optimistic outlook that complexity has no bound and our cosmic party can go on forever. But could this be so? The observed accelerated expansion of the Universe, the most likely explanation of which is a cosmological constant, suggests otherwise. A Universe with a cosmological constant is one that has event horizons—points of no return. And just as Stephen Hawking showed with black holes, the event horizon has a temperature and forms what can be thought of as a sort of box. Whether this means we should think of the Universe as a closed system remains unclear, but if that is the case, the entropy of the system will eventually be maximized. Change will cease, save for fleeting departures from equilibrium, and mundanity will prevail. Let us hope that Barbour is right."

Comment: Far out theories are fun to note, but this author runs counter to most current thought about time and the Big Bang and eventual heat death.

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More weird thinking:

https://www.forbes.com/sites/startswithabang/2020/12/11/ask-ethan-how-do-we-get-enough-...

"...where does all the mass/energy for a multiverse come from? That’s what Professor Laura Templeman wants to know, asking:

“'I don’t know how to explain the multiverse’s mass. If it constantly is splitting into new multiverses where is the conservation of energy? Is it bc gravity is negative energy? Is it because expansion creates more? I am sure I’m missing something elementary but... how we can have enough mass for so many multiverses?”

***

"...no matter how big our Universe actually is, that doesn’t mean it’s the only one. Even if the Universe is infinite, there can be others; remember that some infinities are bigger than others.

"The key to thinking about this is to understand where the (physically motivated) idea of the multiverse actually comes from. It arises if you take seriously the idea of cosmic inflation, which is the best theory and mechanism we have for what came before, set up, and gave rise to the Big Bang itself.

***

"When we look out at the Universe and extrapolate what it must have been like at the start of the hot Big Bang, we find a few puzzling phenomena. We see that it’s the same temperature and density everywhere and in all directions, even though the distant regions to your left and right haven’t had time to exchange information or communicate over the known history of the Universe. We see that the total energy density and the initial expansion rate must have been equal, at the start of the hot Big Bang, to approximately 25 significant digits, something that the Big Bang doesn’t explain. And we see that there are no leftover high-energy signatures from the early Universe, something that would be expected if the Universe rose to infinitely high temperatures and densities early on.

"How is this possible? That’s where the idea of cosmic inflation comes in: perhaps the Universe had a phase preceding the hot Big Bang. In this phase, rather than being filled with particles, antiparticles, radiation, and other quantized forms of energy, the Universe is filled with a form of energy much like dark energy: energy inherent to the fabric of space itself. While it’s in this state, the Universe expands at a relentless, exponential rate. Only when inflation comes to an end does this energy get transferred into particles, antiparticles, and radiation, creating a hot Big Bang.

***

"There’s a lot we don’t know, even in theory, about these multiple Universes, but if inflation is correct and the laws of physics that we know are still valid during it, their existence is all but inevitable. This is where the idea of the multiverse, from a pure physics perspective (with no appeals to philosophy, interpretations of quantum mechanics, or assumptions about the pre-inflationary Universe), arises from.

"That’s where the idea of a Universe from nothing comes from. If “nothing” is the nothingness of empty space, but empty space started off in an inflationary state, not only will it give rise to a Universe like ours, but an extraordinarily large (and possibly infinite) number of independent Universes will arise as well. Each one will be filled with its own particles, antiparticles, radiation, and whatever forms of energy are allowed.

***

"As the Universe expands, the number of particles stays the same, the volume increases, but the total energy remains the same.

***

"Dark energy is also different. It’s an energy inherent to the fabric of space itself: a form of energy that has a small value today, but had a very large value during inflation. As space expands, the energy density remains constant, but the volume increases. The total energy of the Universe goes up over time, since energy equals density multiplied by volume.

***

"The fact is that energy conservation only works at a particular location, not for the expanding Universe. You might have heard the expression that “there’s no such thing as a free lunch.” While that might be true here on Earth, that reasoning doesn’t apply to the expanding Universe. In fact, if ideas like inflation and the multiverse are correct, perhaps the real truth is that the Universe is the ultimate free lunch. In these trying times, this is one thing we can all be thankful for."

Comment: It all depends on which squirrel cage you live in. When Guth developed inflation, in his book he stated the universe had zero energy because gravity is a negative value and everything added up to zero. Siegel says different. When inventing possibilities anything seems to go.

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And may not be fully distinguishable from white dwarfs:

https://www.universetoday.com/149224/is-there-a-way-to-detect-strange-quark-stars-even-...

"The world we see around us is built around quarks. They form the nuclei of the atoms and molecules that comprise us and our world. While there are six types of quarks, regular matter contains only two: up quarks and down quarks. Protons contain two ups and a down, while neutrons contain two downs and an up. On Earth, the other four types are only seen when created in particle accelerators. But some of them could also appear naturally in dense objects such as neutron stars.

"The standard model for neutron stars holds that neutrons remain largely intact within their interior. Thus, a neutron star is like a huge atomic nucleus held together by gravity rather than the strong nuclear force. But we don’t fully understand how neutrons interact at extreme temperatures and densities. It’s possible that within a neutron star the neutrons break down into a soup of quarks, forming what is known as a quark star. Quark stars would look like neutron stars but would be slightly smaller.

***

"...it is worth looking for strange matter objects in the universe, and recently a study has found a few candidates. The study searched for a type of object known as strange dwarfs. These hypothetical objects have a mass similar to a white dwarf, but instead of being made of regular matter in a degenerate state, they are made of strange quark matter. As a result, they would be much smaller than white dwarfs.

***

"If you know the mass and surface gravity of a star, you can easily calculate its radius. The team did this and then compared them to the mass and radius relation for white dwarfs. Most of them followed the relation, but 8 of the stars didn’t. They were much smaller in size and matched predictions for a quark dwarf.

"The data of this work isn’t strong enough to prove these objects are strange dwarfs, but they are worth further study. Something is strange about them, and it would be good to determine whether that’s due to strange quarks or something else."

Comment: We have no explanation as to why the universe is so weird. The human mind has developed the Standard Model and it works just fine. We know the universe is fine-tuned to allow life. We don't understand why quarks are quarks, and the designer isn't talking, but with our brains we can figure out lots of the mysteries. And the moral is survival is not needed to have a brain like this. This clearly means survivability is not an issue which causes any sort of any evolutionary advance. It is an unproven Darwinistic proposal. 'Survival of the fittest' is a tautology, and doesn't tell us how speciation happens.

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Over 13 billion plus light years away:

https://www.scientificamerican.com/article/scientists-think-this-may-be-the-farthest-ga...

"The galaxy GN-z11 might not have a flashy name, but it appears to be the most distant and oldest galaxy ever detected, scientists have found.

***

“From previous studies, the galaxy GN-z11 seems to be the farthest detectable galaxy from us, at 13.4 billion light-years, or 134 nonillion kilometers (that’s 134 followed by 30 zeros),” Kashikawa said in a statement. “But measuring and verifying such a distance is not an easy task.”

"'To determine how far GN-z11 is from us here on planet Earth, Kashikawa’s team studied the galaxy’s redshift—how much its light has stretched out, or shifted toward the red end of the spectrum. In general, the farther away a cosmic object is from us on Earth, the more redshifted its light will be.

"Additionally, the team looked at GN-z11’s emission lines—observable, chemical signatures in the light coming from cosmic objects."

Comment: At 13.4 billion years old it was born just .38 billion years after the Big Bang. A short while before the Milky Way when thinking in billions

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A new exiting method:

https://cosmosmagazine.com/uncategorized/galactic-precision-measurement/?utm_source=Cos...

"Scientists measuring tiny changes in the arrival times of signals from millisecond pulsars have found a new way to measure both gravitational waves and the galaxy’s distribution of dark matter.

"Pulsars are rapidly rotating neutron stars that, like cosmic lighthouses, beam out radio signals that sweep the heavens – beams that can be detected by radio telescopes each time they point in our direction. Millisecond pulsars are ones that do this every few thousandths of a second.

***

"Joseph Simon of the University of Colorado examined more than a dozen years of data from two of the world’s most powerful radio telescopes – Green Bank in West Virginia, US, and Arecibo in Puerto Rico, and found small changes that appear to be due to gravitational waves passing through the Earth.

"These waves, says Simon, toss the entire Earth slightly toward one group of pulsars and away from others, causing their signals to arrive slightly sooner or later than expected. “The only thing we know that causes this pattern is a passing gravitational wave,” he says.

"Not that the Earth is shifting enough for anyone but an astrophysicist to care about. The pulsar signals’ expected arrival times changed by only a few hundred nanoseconds – the equivalent of the Earth being pushed a dozen metres or so over the course of years.

***

“'That allows us to use them as galactic accelerometers,” Chakrabarti says, “much like the accelerometers in your iPhone.”

"It’s not a big effect. In a study of 14 binary pulsars, Chakrabarti found that they were changing velocity by only a few centimetres per second. “That’s roughly the speed of a crawling baby,” she says. “And not a very fast baby, at that.”

"But given the extraordinary precision with which pulsar signals can be measured, it was enough for her team to measure the gravitational field of the galaxy over a sphere about 3200 light years in radius around the Earth.

"From that, she says, it was possible to map out the average density of matter in and around our part of the galaxy, and determine how much of that matter was invisible: dark matter, in other words.

"It’s a finding that may help astrophysicists better understand the role dark matter plays in the galaxy as a whole, but it can also help physicists figure out how to detect it on Earth, by showing how much is in our vicinity.

"And it turns out that there isn’t a lot: only about 7 x 10-25 grams per cubic centimetre. “If I look at the amount of dark matter within the Earth, it’s less than a kilogram,” Chakrabarti says."

Comment: Amazing new methods, with findings both Dawkins and I can agree upon!!!

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Very common:

https://www.universetoday.com/149689/the-universe-in-formation-hubble-sees-6-examples-o...

"10 billion years ago, galaxies of the Universe were ablaze with the light of newly forming stars. This epic phase of history is known as “Cosmic Noon” – the height of all star creation. Galaxies like our Milky Way aren’t creating stars at nearly the rates they were in the ancient past. However, there is a time when galaxies in the present can explode with star formation – when they collide with each other. This recently published collage of merging galaxies by the Hubble HiPEEC survey (Hubble imaging Probe of Extreme Environments and Clusters) highlights six of these collisions which help us understand star formation in the early Universe.

***

"The Milky Way creates between 1.5 to 3 solar masses (mass of our own Sun) worth of stars each year. Colliding galaxies can create upwards of 100 solar masses per year. These six mergers are all in various stages of collision. Galaxies, for all their hundreds of billions of stars, are mainly empty space. It’s actually possible for two galaxies to merge and yet no two individual stars collide with each other. Rather galaxies pass through one another several times until they finally coalesce. Eventually the nuclei of both galaxies merge to become one larger galaxy – an epic cosmic dance routine over billions of years.

***

"The targets were selected because they are oriented face-on meaning Hubble can scan the entire surface of the galaxy for star forming clusters. The clusters themselves are enshrouded by massive clouds of dust and gas, the raw material for star formation.

***

"Interstellar dust causes “extinction” a process where light is literally extinguished as it’s absorbed. However, star forming clusters are powerful sources of infrared light and a particular red light known as Hydrogen-Alpha created by young massive stars blasting hydrogen gas with their intense radiation. Both infrared and H-Alpha can cut through the shroud to be observed by Hubble. Merging galaxies are ablaze with infrared light. Classified as “Luminous Infrared Galaxies” (LIRG) they are brighter in infrared than the entire light spectrum of other galaxies.

***

"Researchers discovered enormous star forming clusters within the merging systems – far larger than found in our own galaxy. The largest young star clusters in the Milky Way can reach tens of thousands of solar masses. As galaxies merge, more and more massive clusters form – the largest created in the later stages of coalescence. NGC 34 features a cluster upwards of 20 million solar masses that is 100 million years old. The younger mergers have a greater percentage of clusters less than 10 million years old indicating the rate of star formation has been steadily increasing.

***

"The raw material to form stars is interstellar hydrogen gas. Galaxies contained a greater abundance and density of this gas in the past which was consumed during Cosmic Noon. Hydrogen remains in galaxies like the Milky Way but the gas isn’t nearly as concentrated resulting in lower rates of star formation and smaller star clusters. The merging of galaxies create tidal forces through gravity that funnel this remaining gas into high density, concentrated regions resulting in massive star forming clusters and a cascade of star formation – a “starburst.”

***

"While the Milky Way doesn’t feature massive young clusters of stars, our galaxy does have very large old clusters of stars known as Globular Clusters. The largest we’ve observed in the Milky Way is called Omega Centauri which contains about 10 million stars weighing in at 4 million solar masses that are billions of years old. The origin of globular clusters is not entirely known but they are thought to originate from the Milky Way’s own collision with other galaxies in the past or formed during Cosmic Noon."

Comment: the text I presented is informative, but the images are breathtaking. As an aside dhw worries that the universe is too large and complicated and wonders why God did it that over-sized way. Not to worry, NASA says the number of galaxies in the hundreds of billions not trillions:

https://justthenews.com/nation/science/experts-say-number-galaxies-universe-may-be-sign...

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Successful landing:

https://www.nature.com/articles/d41586-021-00432-1?utm_source=Nature+Briefing&utm_c...

"NASA’s Perseverance rover touched down safely in Jezero Crater on Mars on 18 February, kicking off a new era of exploration on the red planet in which rocks will be collected and returned to Earth for the first time.

"Encased in a protective heat shield, Perseverance whizzed through the thin Martian atmosphere and then deployed a parachute to slow itself down. In a final landing manoeuvre, a ‘sky crane’ holding the rover fired its rockets to gently lower the six-wheeled, car-sized Perseverance to the surface.

***

"The landing went as smoothly as engineers had hoped. "I almost feel like we're in a dream," says Jennifer Trosper, the mission's deputy project manager at the Jet Propulsion Laboratory (JPL) in Pasadena, California. In the coming hours and days, the rover will photograph more of its surroundings and begin testing the scientific instruments it carries.

"The mission’s goal is to roll around Jezero Crater and collect rock samples from the river delta and an ancient lake that might hold evidence of past Martian life. Ultimately, the rover will leave those samples at certain spots on the Martian ground where future spacecraft can retrieve them — making Perseverance the first step in a multi-decadal effort to bring Mars rocks to Earth."

Comment: Just bringing the news to this site.

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landing video:

https://youtu.be/TWFYHKFwQVY

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Getting eough cold gas:

https://phys.org/news/2021-02-cold-gas-pipelines-early-massive.html

"To come into being, galaxies need a steady diet of cold gases to undergo gravitational collapse. The larger the galaxy, the more cold gas it needs to coalesce and to grow.

"Massive galaxies found in the early universe needed a lot of cold gas—a store totaling as much as 100 billion times the mass of our sun.

"But where did these early, super-sized galaxies get that much cold gas when they were hemmed in by hotter surroundings?

"In a new study, astronomers led by the University of Iowa report direct, observational evidence of streams of cold gas they believe provisioned these early, massive galaxies. They detected cold gas pipelines that knifed through the hot atmosphere in the dark matter halo of an early massive galaxy, supplying the materials for the galaxy to form stars.

"About two decades ago, physicists working with simulations theorized that during the early universe, cosmic filaments ferried cold gas and embryonic, node-shaped galaxies to a dark matter halo, where it all clumped together to form massive galaxies. The theory assumed the filaments would need to be narrow and densely filled with cold gas to avoid being peeled off by the hotter surrounding atmosphere.

***

"Crucially, the researchers located two background quasars that are projected at close angular distances to the target galaxy, much like how Jupiter and Saturn's motion drew them closer to each other when viewed from Earth during the Great Conjunction last December. Due to this unique configuration, the quasars' light penetrating the halo gas of the foreground galaxy left chemical "fingerprints" that confirmed the existence of a narrow stream of cold gas.

"Those chemical fingerprints showed the gas in the streams had a low concentration of heavy elements such as aluminum, carbon, iron, and magnesium. Since these elements are formed when the star is still shining and are released into the surrounding medium when the star dies, the researchers determined the cold gas streams must be streaming in from outside, rather than being expelled from the star-making galaxy itself.

"'Among the 70,000 starburst galaxies in our survey, this is the only one associated with two quasars that are both nearby enough to probe the halo gas. Even more, both quasars are projected on the same side of the galaxy so that their light can be blocked by the same stream at two different angular distances." Fu says. "So, I feel extremely fortunate that natureprovided us this opportunity to detect this major artery leading to the heart of a phenomenal galaxy during its adolescence.'"

Comment: The Milky Way is a giant galaxy, and this tells us how it formed.

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All done in star factories by different systems:

https://phys.org/news/2021-02-radioactivity-meteorites-heaviest-elements-solar.html

"Heavy elements we encounter in our everyday life, like iron and silver, did not exist at the beginning of the universe, 13.7 billion years ago. They were created in time through nuclear reactions called nucleosynthesis that combined atoms together. In particular, iodine, gold, platinum, uranium, plutonium, and curium, some of the heaviest elements, were created by a specific type of nucleosynthesis called the rapid neutron capture process, or r process.

"...it is thought that the r process can occur during violent collisions between two neutron stars, between a neutron star and a black hole, or during rare explosions following the death of massive stars. Such highly energetic events occur very rarely in the universe. When they do, neutrons are incorporated in the nucleus of atoms, then converted into protons. Since elements in the periodic table are defined by the number of protons in their nucleus, the r process builds up heavier nuclei as more neutrons are captured.

"Some of the nuclei produced by the r process are radioactive and take millions of years to decay into stable nuclei. Iodine-129 and curium-247 are two of such nuclei that were pro-duced before the formation of the sun. They were incorporated into solids that eventually fell on the earth's surface as meteorites. Inside these meteorites, the radioactive decay generat-ed an excess of stable nuclei. Today, this excess can be measured in laboratories in order to figure out the amount of iodine-129 and curium-247 that were present in the solar system just before its formation.

"Why are these two r-process nuclei are so special? They have a peculiar property in com-mon: they decay at almost exactly the same rate. In other words, the ratio between iodine-129 and curium-247 has not changed since their creation, billions of years ago.

"'This is an amazing coincidence, particularly given that these nuclei are two of only five ra-dioactive r-process nuclei that can be measured in meteorites," says Benoit Co?te? from the Konkoly Observatory, the leader of the study. "With the iodine-129 to curium-247 ratio being frozen in time, like a prehistoric fossil, we can have a direct look into the last wave of heavy element production that built up the composition of the solar system, and everything within it." (my bold)

***

"The team calculated the iodine-129 to curium-247 ratios synthesized by collisions between neutron stars and black holes to find the right set of conditions that reproduce the composition of meteorites. They concluded that the amount of neutrons available during the last r-process event before the birth of the solar system could not be too high. Otherwise, too much curium would have been created relative to iodine. This implies that very neutron-rich sources, such as the matter ripped off the surface of a neutron star during a collision, likely did not play an important role.

"So what created these r-process nuclei? While the researchers could provide new and insightful information regarding how they were made, they could not pin down the nature of the astronomical object that created them. This is because nucleosynthesis models are based on uncertain nuclear properties, and it is still unclear how to link neutron availability to specific astronomical objects such as massive star explosions and colliding neutron stars."

Comment: Note my bold. It seems like we have found evidence of the fine tuner in action. We need all the elements that were built in stars for life to exist. They are all built up starting from hydrogen which was first to form and isin huge supply

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There are wild unproveable ideas being propagated:

https://aeon.co/essays/post-empirical-science-is-an-oxymoron-and-it-is-dangerous?utm_so...

"There is no agreed criterion to distinguish science from pseudoscience, or just plain ordinary bullshit, opening the door to all manner of metaphysics masquerading as science. This is ‘post-empirical’ science, where truth no longer matters, and it is potentially very dangerous.

***

"When it comes to grabbing attention, inviting that all-important click, or purchase, speculative metaphysics wins hands down.

***

"Leah Broussard ...betrays the nature of the game that’s being played when she says: ‘Theorists are very good at evading the traps that experimentalists leave for them. You’ll always find someone who’s happy to keep the idea alive.’

"The ‘mirrorverse’ is just one more in a long line of so-called multiverse theories. These theories are based on the notion that our Universe is not unique, that there exists a large number of other universes that somehow sit alongside or parallel to our own...As Broussard explained, these theories are sufficiently slippery to duck any kind of challenge that experimentalists might try to throw at them, and there’s always someone happy to keep the idea alive. (Comment: many examples follow)

***

"..we seriously limit our ability to lift the veils of ignorance and change antiscientific beliefs if we persist in peddling this absurdly simplistic view of what science is. To understand why post-empirical science is even possible, we need first to dispel some of science’s greatest myths.

***

"It turns out to be impossible even to formulate a scientific theory without metaphysics, without first assuming some things we can’t actually prove, such as the existence of an objective reality and the invisible entities we believe to exist in it. This is a bit awkward because it’s difficult, if not impossible, to gather empirical facts without first having some theoretical understanding of what we think we’re doing. Just try to make any sense of the raw data produced by CERN’s Large Hadron Collider without recourse to theories of particle physics, and see how far you get.

***

"...for me at least, there has to be a difference between science and pseudoscience; between science and pure metaphysics, or just plain ordinary bullshit.

***

"If the evidence verifies the theory, that’s great – we celebrate and start looking for another test. If the evidence fails to support the theory, then we might ponder for a while or tinker with the auxiliary assumptions. Either way, there’s a tension between the metaphysical content of the theory and the empirical data – a tension between the ideas and the facts – which prevents the metaphysics from getting completely out of hand. In this way, the metaphysics is tamed or ‘naturalised’, and we have something to work with. This is science.

***

"...our best theories are full of explanatory holes. Bringing them together in a putative theory of everything has proved to be astonishingly difficult. Despite much effort over the past 50 years, there is no real consensus on how this might be done. And, to make matters considerably worse, we’ve run out of evidence. The theorists have been cunning and inventive. They have plenty of metaphysical ideas but there are no empirical signposts telling them which path they should take. They are ideas-rich, but data-poor.

***

"The ‘best explanation’ is then based on a choice between purely metaphysical constructs, without reference to empirical evidence, based on the application of a probability theory that can be readily engineered to suit personal prejudices.

Welcome to the oxymoron that is post-empirical science. (my bold)

***

"Perhaps we should begin with a small first step. Let’s acknowledge that theoretical physicists are perfectly entitled to believe, write and say whatever they want, within reason. But is it asking too much that they make their assertions with some honesty? "

Comment: All current science news is filled with hype and obvious biases egged on by over-the-top wild eyed theorists not interested in only provable points. The Higgs boson was predicted by good theory using real results for over 40 years. That was good, real science. Read articles while wary of obvious bias.

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Very important for us to understand:

https://phys.org/news/2021-03-astrophysicist-theory-sun-composition-varies.html

"About 17 years ago, J. Martin Laming, an astrophysicist at the U.S. Naval Research Laboratory, theorized why the chemical composition of the Sun's tenuous outermost layer differs from that lower down. His theory has recently been validated by combined observations of the Sun's magnetic waves from the Earth and from space.

"His most recent scientific journal article describes how these magnetic waves modify chemical composition in a process completely new to solar physics or astrophysics, but already known in optical sciences, having been the subject of Nobel Prizes awarded to Steven Chu in 1997 and Arthur Ashkin in 2018.

***

"The Sun is made up of many layers. Astronomers call its outermost layer the solar corona, which is only visible from earth during a total solar eclipse. All solar activity in the corona is driven by the solar magnetic field. This activity consists of solar flares, coronal mass ejections, high-speed solar wind, and solar energetic particles. These various manifestations of solar activity are all propagated or triggered by oscillations or waves on the magnetic field lines.

"'The very same waves, when they hit the lower solar regions, cause the change in chemical composition, which we see in the corona as this material moves upwards," Laming said. "In this way, the coronal chemical composition offers a new way to understand waves in the solar atmosphere, and new insights into the origins of solar activity."

***

"'We estimate that the Sun is 91 percent hydrogen but the small fraction accounted for by minor ions like iron, silicon, or magnesium dominates the radiative output in ultraviolet and X-rays from the corona," he said. "If the abundance of these ions is changing, the radiative output changes."

"'What happens on the Sun has significant effects on the Earth's upper atmosphere, which is important for communication and radar technologies that rely on over-the-horizon or ground-to-space radio frequency propagation," Englert said.

"It also has an impact on objects in orbit. The radiation is absorbed in the Earth's upper atmospheric layers, which causes the upper atmosphere to form plasma, the ionosphere, and to expand and contract, influencing the atmospheric drag on satellites and orbital debris.

"'The Sun also releases high energy particles," Laming said. "They can cause damage to satellites and other space objects. The high energy particles themselves are microscopic, but it's their speed that causes them to be dangerous to electronics, solar panels, and navigation equipment in space.'"

Comment: Other stars must do the same things. We are protected on the Earth's surface in part by our magnetic field and the ozone layer. part of the Earth being called a privileged planet.

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Current measurement doesn't fit theory:

https://www.sciencenews.org/article/muon-physics-standard-model-particles

"In a painstakingly precise experiment, muons’ gyrations within a magnetic field seem to defy predictions of the standard model of particle physics, which describes known fundamental particles and forces. The result strengthens earlier evidence that muons, the heavy kin of electrons, behave unexpectedly.

“'It’s a very big deal,” says theoretical physicist Bhupal Dev of Washington University in St. Louis. “This could be the long-awaited sign of new physics that we’ve all hoped for.”

"Muons’ misbehavior could point to the existence of new types of particles that alter muons’ magnetic properties. Muons behave like tiny magnets, each with a north and south pole. The strength of that magnet is tweaked by transient quantum particles that constantly flit into and out of existence, adjusting the muon’s magnetism by an amount known as the muon magnetic anomaly. Physicists can predict the value of the magnetic anomaly by considering the contributions of all known particles. If any fundamental particles are in hiding, their additional effects on the magnetic anomaly could give them away.

***

"A previous measurement of this type, from an experiment completed in 2001 at Brookhaven National Laboratory in Upton, N.Y., also seemed to disagree with theoretical predictions (SN: 2/15/01). When the new result is combined with the earlier discrepancy, the measurement diverges from the prediction by a statistical measure of 4.2 sigma — tantalizingly close to the typical five-sigma benchmark for claiming a discovery. “We have to wait for more data from the Fermilab experiment to really be convinced that this is a real discovery, but it is becoming more and more interesting,” says theoretical physicist Carlos Wagner of the University of Chicago."

Comment: Wow!!! We have to patiently wait.

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Current measurement doesn't fit theory:

https://www.sciencenews.org/article/muon-physics-standard-model-particles

Comment: Wow!!! We have to patiently wait. And immediately maybe not:

https://www.quantamagazine.org/muon-g-2-experiment-at-fermilab-finds-hint-of-new-partic...

"even as many particle physicists are likely to be celebrating — and racing to propose new ideas that could explain the discrepancy — a paper published today in the journal Nature casts the new muon measurement in a dramatically duller light.

"The paper, which appeared just as the Fermilab team unveiled its new measurement, suggests that the muon’s measured wobbliness is exactly what the Standard Model predicts.

"In the paper, a team of theorists known as BMW present a state-of-the-art supercomputer calculation of the most uncertain term that goes into the Standard Model prediction of the muon’s magnetic moment. BMW calculates this term to be considerably larger than the value adopted last year by the consortium, a group known as the Theory Initiative. BMW’s larger term leads to a larger overall predicted value of the muon’s magnetic moment, bringing the prediction in line with the measurements.

***

"MW’s calculation itself is not breaking news; the paper first appeared as a preprint last year. Aida El-Khadra, a particle theorist at the University of Illinois who co-organized the Theory Initiative, explained that the BMW calculation should be taken seriously, but that it wasn’t factored into the Theory Initiative’s overall prediction because it still needed vetting. If other groups independently verify BMW’s calculation, the Theory Initiative will integrate it into its next assessment.

"Dominik Stöckinger, a theorist at the Technical University of Dresden who participated in the Theory Initiative and is a member of the Fermilab Muon g-2 team, said the BMW result creates “an unclear status.” Physicists can’t say whether exotic new particles are pushing on muons until they agree about the effects of the 17 Standard Model particles they already know about.

"Regardless, there’s plenty of reason for optimism: Researchers emphasize that even if BMW is right, the puzzling gulf between the two calculations could itself point to new physics. But for the moment, the past 20 years of conflict between theory and experiment appear to have been replaced by something even more unexpected: a battle of theory versus theory.

***

"An electron or muon might emit and reabsorb two photons, or a photon that briefly becomes an electron and a positron, among countless other possibilities that the Standard Model allows. These temporary manifestations travel around with an electron or muon like an entourage, and all of them contribute to its magnetic properties. “The particle you thought was a bare muon is actually a muon plus a cloud of other things that appear spontaneously,” said Chris Polly, another leader of the Fermilab Muon g-2 experiment. “They change the magnetic moment.”

***

"Throughout the 2010s, the $20 billion Large Hadron Collider in Europe slammed protons together in hopes of conjuring up dozens of new particles that might complete the pattern of nature’s building blocks. But the collider found only the Higgs boson — the last missing piece of the Standard Model. Meanwhile, a slew of experimental searches for dark matter found nothing. Hopes for new physics increasingly rode on wobbly muons. “I don’t know if it is the last great hope for new physics, but it certainly is a major one,” Matthew Buckley, a particle physicist at Rutgers University, told me."

Comment: so, it is still a waiting game.

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Using fast radio bursts is a new method:

https://www.sciencenews.org/article/fast-radio-bursts-universe-expansion-hubble-constant

"For the first time, astronomers calculated the Hubble constant — the rate at which the universe is expanding — from observations of cosmic flashes called fast radio bursts, or FRBs. While the results are preliminary and the uncertainties are large, the technique could mature into a powerful tool for nailing down the elusive Hubble constant, researchers report April 12 at arXiv.org.

***

Astronomers typically measure the Hubble constant in two ways. One uses the cosmic microwave "background, the light released shortly after the Big Bang, in the distant universe. The other uses supernovas and other stars in the nearby universe. These approaches currently disagree by a few percent. The new value from FRBs comes in at an expansion rate of about 62.3 kilometers per second for every megaparsec (about 3.3 million light-years). While lower than the other methods, it’s tentatively closer to the value from the cosmic microwave background, or CMB.

“'Our data agrees a little bit more with the CMB side of things compared to the supernova side, but the error bar is really big, so you can’t really say anything,” says Steffen Hagstotz, an astronomer at Stockholm University. Nonetheless, he says, “I think fast radio bursts have the potential to be as accurate as the other methods.”

***

“'It’s a first measurement, so not too surprising that the current results are not as constraining as other more matured probes,” says Birrer.

"New FRB data might be coming soon. Many new radio observatories are coming online and larger surveys, such as ones proposed for the Square Kilometer Array, could discover tens to thousands of FRBs every night. Hagstotz expects there will sufficient FRBs with distance estimates in the next year or two to accurately determine the Hubble constant. Such FRB data could also help astronomers understand what’s causing the bright outbursts."

Comment: The universe is still so confusing, we don't really understands how God madeit work, but we know it is fine-tuned for life to appear.

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All others fall by the wayside:

https://www.forbes.com/sites/startswithabang/2021/05/06/why-isnt-anyone-seriously-chall...

"As recently as 20 years ago, the Big Bang was one of many ideas that scientists continued to entertain: quasi-steady state theory, plasma cosmology, and quantized redshifts remained mainstays in the scientific literature. But today, it’s largely crackpots and a few fringe contrarians who muster even the flimsiest of challenges to the consensus position: that the Universe began with a hot Big Bang. Is the field of cosmology succumbing to groupthink, as its detractors often claim, or is the lack of alternatives justified? Let’s dive in and find out.

***

"But in Einstein’s General Relativity, only a few spacetimes are exactly solvable, and they’re all relatively simple cases. For instance:

"We can solve an empty Universe: that’s Minkowski space.
We can solve for a Universe with one uncharged, non-rotating mass: the Schwarzschild solution.
We can write down the equations for a Universe containing one massive, rotating object: the Kerr solution.
And we can solve the equations governing spacetime for a Universe that’s uniformly filled with matter and radiation: we get the Friedmann equations.
This last option, as was recognized almost immediately, could represent our Universe. If our Universe is homogeneous (the same in all location) and isotropic (the same in all directions), even on average, even only on the largest of cosmic scales, the Friedmann equations will tell us how the Universe evolves over time.

***

"What the Big Bang hypothesized was that the volume which the objects within our Universe occupied increased over time, and hence the Universe got less dense as time went on, as well as cooler, as light within it became shifted to longer wavelengths and lower temperatures.

"But in addition to extrapolating forwards, we could extrapolate backwards in time as well: to a hotter, denser state. In fact, there was no limit to this, in principle. We could go back to arbitrarily high temperatures and arbitrarily large densities, and if the Big Bang were correct, the act of expanding and cooling during the evolution of the cosmos would lead to three major predictions, in addition to the expanding Universe.

***

"This leftover glow — originally called the primeval fireball and today known as the cosmic microwave background — was discovered in the mid-1960s, and has been verified to be blackbody in spectrum and to have imperfections in it at the 1-part-in-30,000 level.

***

"But because of how quickly the Universe expands and cools, these reactions can only take place briefly. After the dust settles, the Universe becomes about 75% hydrogen, 25% helium-4, 0.01% each helium-3 and deuterium, and about 0.0000001% lithium-7. The science of Big Bang Nucleosynthesis — the process by which these elements are formed — is now standard fare for graduate students, and has been observationally validated for galaxies, quasars, gas clouds, and from the cosmic microwave background as well.

"The overwhelming agreement between the Big Bang’s predictions and these observations — including in greater and greater detail — was what led to its widespread acceptance. Initial alternatives fell by the wayside as:

"non-relativistic ideas, like the Milne Universe, failed to account for the subsequently verified tests of General Relativity, like the Pound-Rebka experiments,
the idea of tired light cosmology, where redshift was due to light losing energy as it traveled through space, was discredited by the observed sharpness of distant galaxies,
and the idea of the early Steady State Theory, which predicted a low-energy, background glow of reflected starlight, failed to match the observed spectrum of the cosmic microwave background.

***

"Today, the only serious challenges to the standard Big Bang picture come in the form of add-ons: Universes where exotic forms of matter or energy (including dark matter and dark energy) are present, Universes that depart significantly (but within the observational limits) from isotropy or homogeneity, Universes with a different theory of gravity than General Relativity (but that don’t conflict with any of General Relativity’s already-observed successes). All of the modern alternatives still possess a hot, dense, uniform, and rapidly expanding early state, which expands, cools, and gravitates to form the Universe we see today.

***

"If any scientifically viable alternatives to the Big Bang ever arise, almost every modern cosmologist would thoroughly welcome it, and then immediately put it to the test. The problem is that every such alternative is already ruled out by the evidence in hand. Until an idea arises that meets those necessary criteria, the Big Bang will stand alone as the only idea compatible with the full suite of data we now possess."

Comment: The Big Bang still survives over all others

5475 views

Galaxies have mixed ways of making new stars:

https://phys.org/news/2021-06-cosmic-cartographers-nearby-universe-revealing.html

"A team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) has completed the first census of molecular clouds in the nearby universe, revealing that contrary to previous scientific opinion, these stellar nurseries do not all look and act the same. In fact, they're as diverse as the people, homes, neighborhoods and regions that make up our own world.

"Stars are formed out of clouds of dust and gas called molecular clouds, or stellar nurseries. Each stellar nursery in the universe can form thousands or even tens of thousands of new stars during its lifetime. Between 2013 and 2019, astronomers on the PHANGS project (Physics at High Angular Resolution in Nearby GalaxieS) conducted the first systematic survey of 100,000 stellar nurseries across 90 galaxies in the nearby universe to get a better understanding of how they connect back to their parent galaxies.

***

"To better understand star formation in different types of galaxies, the team observed similarities and differences in the molecular gas properties and star formation processes of galaxy disks, stellar bars, spiral arms, and galaxy centers. They confirmed that the location, or neighborhood, plays a critical role in star formation.

"'By mapping different types of galaxies and the diverse range of environments that exist within galaxies, we are tracing the whole range of conditions under which star-forming clouds of gas live in the present-day universe. This allows us to measure the impact that many variables have on the way star formation happens," said Guillermo Blanc, an astronomer at the Carnegie Institution for Science, and a co-author on the paper.

***

"Annie Hughes, an astronomer at L'Institut de Recherche en Astrophysique et Planétologie (IRAP), added that this is the first time scientists have a snapshot of what star-forming clouds are really like across such a broad range of different galaxies. "We found that the properties of star-forming clouds depend on where they are located: clouds in the dense central regions of galaxies tend to be more massive, denser, and more turbulent than clouds that reside in the quiet outskirts of a galaxy. The lifecycle of clouds also depends on their environment. How fast a cloud forms stars and the process that ultimately destroys the cloud both seem to depend on where the cloud lives.'"

Comment: this will only add to dhw's confusion as to why God created this universe, which is not uniform everywhere. We still don't have many answers about the mysteries we observe. The simplest approach is to accept God's doings and then figure out why.

5358 views

Dark matter must exist:

https://www.forbes.com/sites/startswithabang/2020/01/20/this-is-how-galaxy-cluster-coll...

"Dark matter — despite the enormous indirect evidence for it — sounds like a colossal misunderstanding.

"It's clear that data from gravitational lensing, galaxy clustering, and the cosmic microwave background, all require masses that don't interact electromagnetically.

"The way galaxies cluster together is impossible to achieve in a Universe without dark matter. The... [+] clustering patterns seen due to baryon acoustic oscillations, imprinted in the Universe's power spectrum, and on the largest scales of the cosmic web are all consistent with dark matter, but have never been explicable via any attempted modification of gravity.

"However, a longstanding alternative suggests modifying gravity could explain them without dark matter.

"In 2005, a team of astronomers devised a clever test to investigate dark matter's existence.

"When two galaxy clusters collide — a cosmically rare but important event — its internal components behave differently.

"The intergalactic gas must collide, slow, and heat up, creating shocks and emitting X-rays.

"If there were no dark matter, this gas, comprising the majority of normal matter, should be the primary source of gravitational lensing.

"Instead, gravitational lensing maps indicate that most of the mass is displaced from the normal matter.

"This remains true for every set of post-collisional X-ray clusters ever measured.

"Only if gravity is non-local, or gravitating where the matter isn't, could the Universe not contain dark matter.

"But in pre-merger clusters, we clearly see that gravity is local: matter and gravity line up.

"Colliding clusters cannot obey different gravitational rules from non-colliding ones.

"Inescapably, dark matter must therefore exist."

Comment: So matter we cannot see is proven. It is not necessary for all matter to light up, no matter that much does. But is needed to hold galaxies together.

5324 views

Just th opposite to our solar system:

https://www.sciencenews.org/article/planet-tilt-orbit-star-pole-astronomy-space

"Astronomers Simon Albrecht and Marcus Marcussen at Aarhus University in Denmark and colleagues analyzed 57 planets in other solar systems for which the researchers could determine the true tilt between a planet’s orbit and its star’s equatorial plane. Two-thirds of the planets have normal orbits, tilted no more than 40 degrees, the team found. The other 19 planets are misaligned.

"But the orbits of those misaligned planets don’t make just any old angle with their star’s equator. Instead, they pile up around 90 degrees. In fact, all but one of the misaligned planets are on polar orbits, having tilts from 80 to 125 degrees, the astronomers report online May 20 at arXiv.org.

***

"The result may lend insight into the biggest mystery about these planets: how they arose (SN: 10/18/13). Such worlds were a shock to astronomers, because planets form inside pancake-shaped disks of gas and dust orbiting in their stars’ equatorial planes. Thus, planets should lie near the plane of their sun’s equator, too. In our solar system, for example, Earth’s orbit tilts only 7 degrees from the solar equatorial plane, and even Pluto — which many astronomers no longer call a planet — has an orbit tilted only 12 degrees from that plane (and 17 degrees from the Earth’s orbital plane).

“'At the moment, we are not sure what is the underlying mechanism” or mechanisms for creating misaligned planets, Albrecht admits. Whatever it is, though, it should account for the newly discovered plethora of perpendicular planets, he says.

"A possible clue, Albrecht says, comes from the single exception to the rule: the one misaligned planet in the sample that is not on a polar orbit. This planet also happens to be the most massive in the sample, packing the mass of between five and eight Jupiters. Albrecht says that may be just a coincidence — or it may reveal something about how the other planets became misaligned.

"In the future, the astronomers hope to understand how these wayward worlds acquired their odd orbits. All known misaligned planets orbit close to their stars, but are these worlds more likely than normal, close-in planets to have giant planets near them? The scientists don’t yet know, but if they find such a correlation, those companions may have somehow flung these bizarre worlds onto their peculiar planetary paths."

Comment: Obviously all parts of the universe are not the same. Should they necessarily be similar? It is certainly possible some processes of evolution of the universe can have different results.

5313 views

Everything does spin and no one knows why:

https://www.newscientist.com/article/2280743-enormous-strands-of-galaxies-in-the-cosmic...

"Some of the largest structures in the universe appear to be rotating. The filaments of galaxies forming the cosmic web that stretches between galaxy clusters seem to be spinning, which could help us figure out why galaxies themselves – and everything else in space – rotate.

"How rotation is generated in space is a long-standing problem in astrophysics. “Not only are the galaxies spinning, but also the stars within the galaxies, and the Earth is spinning, and the Earth around the sun and the moon around the Earth. Pretty much the whole universe is spinning,” says Noam Libeskind at the Leibniz Institute for Astrophysics Potsdam in Germany. “We don’t really know why, and one way to try to answer that is to figure out where the spinning stops.”

"Previous research has suggested that clusters of galaxies may be the end of the road for spinning, but Libeskind and his colleagues have found that isn’t the case. They used data from the Sloan Digital Sky Survey to examine the colossal filaments of galaxies that make up the cosmic web, which stretch across hundreds of millions of light years, and found that they are rotating.

"We cannot measure rotation directly on such large scales, so the researchers looked for patterns in the galaxies moving towards or away from Earth. When most of the galaxies on one side of a filament were moving away from us and most on the other were coming towards us, that indicated that the whole filament was rotating. Some of these gigantic strands of galaxies were spinning at nearly 100 kilometres per second.

"As the galaxies orbited the centres of their filaments, they also fell towards the galaxy clusters that mark the ends of each strand. “These galaxies are moving on these corkscrew-like, helical orbits,” says Libeskind. The filaments that ended at more massive clumps of galaxies seemed to rotate faster, but it isn’t yet clear why. More work will be required to answer that question, as well as the question of how the filaments’ rotation affects the spins of the galaxies themselves."

Comment: We keep finding new mysteries in God's creation to study. Day and night are good for us living creatures who have to sleep. Is that the reason? That idea makes us very important

5314 views

The use of math at times clouds issues:

https://www.realclearscience.com/2021/06/15/the_universe_is_not_made_of_mathematics_781...

"In their seeking of simplicity, scientists fall into error. They mistake their abstract concepts describing reality – for reality itself. The map for the territory. This leads to dogmatic overstatements, paradoxes and mysteries such as quantum gravity. To avoid such errors, we should evoke the thinking of philosopher Alfred North Whitehead and conceive of the universe as a universe-in-process, where physical relations beget new physical relations,

"So when Lawrence Krauss publicly called David Albert a “moron” for not appreciating the significance of Krauss’s discovery of the concrete physics of nothingness, it caused quite a stir. In his book, A Universe from Nothing, Krauss argued that in the same way quantum field theory depicts the creation of particles from a region of spacetime devoid of particles (a quantum vacuum), quantum mechanics, if sufficiently generalized, could depict the creation of spacetime itself from pure nothingness. In a scathing review of Krauss’s book, Albert argued that claiming that physics could concretize “nothing” in this way was at best naïve, and at worst disingenuous. Quantum mechanics is a physical theory, operative only in a physical universe. To contort it into service as a cosmological engine that generates the physical universe from “nothing” requires that the abstract concept of “nothing” be concretized as physical so that the mechanics of quantum mechanics can function. What’s more, if quantum mechanics is functional enough to generate the universe from nothing, then it’s not really nothing; it’s nothing plus quantum mechanics.

***

"During the first years of modern mathematical physics and the construction of its two central pillars, quantum theory and relativity theory, Alfred North Whitehead warned, “There is no more common error than to assume that, because prolonged and accurate mathematical calculations have been made, the application of the result to some fact of nature is absolutely certain.”

"Whitehead would later generalize this as the “fallacy of misplaced concreteness.” It is often oversimplified as merely mistaking an abstract conceptual object, like a mathematical or logical structure (e.g., the number zero), for a concrete physical object. But the fallacy has more to do with what Whitehead argued was the chief error in science and philosophy: dogmatic overstatement. We commit the fallacy of misplaced concreteness when we identify any object, conceptual or physical, as universally fundamental when, in fact, it only exemplifies selective categories of thought and ignores others. In modern science, the fallacy of misplaced concreteness usually takes the form of a fundamental reduction of some complex feature of nature—or even the universe itself—to some simpler framework. When that framework fails, it is replaced with a new reduction—a new misplaced concreteness, and the cycle repeats.

***

“'The aim of science,” Whitehead writes, “is to seek the simplest explanations of complex facts. We are apt to fall into the error of thinking that the facts are simple because simplicity is the goal of our quest. The guiding motto in the life of every natural philosopher should be, ‘Seek simplicity and distrust it.’” And then investigate further.

***

"When viewed through the lens of the fallacy of misplaced concreteness, the root of this crisis is clear: the general theory of relativity concretizes spacetime as a continuum. The problem with this, as Zeno famously demonstrated, is the infinite divisibility of a finite interval—the finite containing the infinite—which is fine if you’re thinking about numbers alone, but highly problematic for physics.

***

"Quantum mechanics was explicitly designed to immunize physics against such concretized infinites and their associated paradoxes, and this is the heart of its incompatibility with the general theory of relativity. It avoids the misplaced concreteness of a fundamental continuum by instead describing physical systems as serial “physical histories” of discrete, physical states. But quantum mechanics is not without its own misplaced concretizations... Quantum mechanics contains no physical “mechanism” to explain this; it only contains mathematical structures that describe the process.

***

"It is not surprising that it took a mathematician and philosopher as brilliant as Whitehead to emphasize the fallacy of misplaced concreteness and its hazards, or that the most promising solutions to our current problems in fundamental physics would be those that explicitly aim to avoid that fallacy. Deconstructing the “simple” and “self-evident” concretized categories by which we habitually (and often dogmatically) coordinate our thoughts and experiences of the world…this, for Whitehead, was the only route to progress. “If science is not to degenerate into a medley of ad hoc hypotheses,” he writes, “it must become philosophical and must enter upon a thorough criticism of its own foundations.” While it’s true that the strongest foundations are often concretized, it is equally true that this strength always begins and ends with what lies beneath."

Comment: This is why we have crazy string theory that won't work and won't die.

5328 views

Stephen Hawking prediction about merging black holes proven:

https://www.sciencenews.org/article/gravitational-waves-confirm-black-hole-law-predicte...

"Despite their mysterious nature, black holes are thought to follow certain simple rules. Now, one of the most famous black hole laws, predicted by physicist Stephen Hawking, has been confirmed with gravitational waves.

"According to the black hole area theorem, developed by Hawking in the early 1970s, black holes can’t decrease in surface area over time. The area theorem fascinates physicists because it mirrors a well-known physics rule that disorder, or entropy, can’t decrease over time. Instead, entropy consistently increases

***

"The surface area of a lone black hole won’t change — after all, nothing can escape from within. However, if you throw something into a black hole, it will gain more mass, increasing its surface area. But the incoming object could also make the black hole spin, which decreases the surface area. The area law says that the increase in surface area due to additional mass will always outweigh the decrease in surface area due to added spin.

***

"According to the area theorem, the area of the newly formed black hole’s event horizon should be at least as big as the areas of the event horizons of the two original black holes combined.

"The team analyzed data from the first gravitational waves ever spotted, which were detected by the Advanced Laser Interferometer Gravitational-Wave Observatory, LIGO, in 2015 (SN: 2/11/16). The researchers split the gravitational wave data into two time segments, before and after the merger, and calculated the surface areas of the black holes in each period. The surface area of the newly formed black hole was greater than that of the two initial black holes combined, upholding the area law with a 95 percent confidence level, the team reports in a paper to appear in Physical Review Letters.

***

"The area theorem is a result of the general theory of relativity, which describes the physics of black holes and gravitational waves. Previous analyses of gravitational waves have agreed with predictions of general relativity, and thus already hinted that the area law can’t be wildly off. But the new study “is a more explicit confirmation,” of the area law, says physicist Cecilia Chirenti of the University of Maryland in College Park, who was not involved with the research.

"So far, general relativity describes black holes well. But scientists don’t fully understand what happens where general relativity — which typically applies to large objects like black holes — meets quantum mechanics, which describes small stuff like atoms and subatomic particles. In that quantum realm, strange things can happen."

Comment: But despite Whitehead's warning theoretical math theorists still make correct predictions. However, whitehead's quantum theory comments still are correct, as the last paragraph notes.

5320 views

Finally measured:

https://www.ucl.ac.uk/news/2021/jun/dark-matter-slowing-spin-milky-ways-galactic-bar

"The spin of the Milky Way’s galactic bar, which is made up of billions of clustered stars, has slowed by about a quarter since its formation, according to a new study by UCL and University of Oxford researchers.

***

"In the study, published in the Monthly Notices of the Royal Astronomical Society, researchers analysed Gaia space telescope observations of a large group of stars, the Hercules stream, which are in resonance with the bar – that is, they revolve around the galaxy at the same rate as the bar’s spin.

"These stars are gravitationally trapped by the spinning bar. The same phenomenon occurs with Jupiter's Trojan and Greek asteroids, which orbit Jupiter's Lagrange points (ahead and behind Jupiter). If the bar’s spin slows down, these stars would be expected to move further out in the galaxy, keeping their orbital period matched to that of the bar’s spin.

"The researchers found that the stars in the stream carry a chemical fingerprint – they are richer in heavier elements (called metals in astronomy), proving that they have travelled away from the galactic centre, where stars and star-forming gas are about 10 times as rich in metals compared to the outer galaxy.

"Using this data, the team inferred that the bar – made up of billions of stars and trillions of solar masses – had slowed down its spin by at least 24% since it first formed.

"Co-author Dr Ralph Schoenrich (UCL Mullard Space Science Laboratory) said: “Astrophysicists have long suspected that the spinning bar at the centre of our galaxy is slowing down, but we have found the first evidence of this happening.

“'The counterweight slowing this spin must be dark matter. Until now, we have only been able to infer dark matter by mapping the gravitational potential of galaxies and subtracting the contribution from visible matter."

***

Comment: Full turning speed forever was never considered. More evidence for dark matter producing drag.

5315 views

A weird review of a book:

https://www.realclearscience.com/2021/06/18/is_the_universe_open-ended_781996.html?utm_...

"Every equation of physics or every computer simulation of how planets, stars, and galaxies orbit and evolve, is a bizarre imprint of an interpretation of the universe by the universe, built into the universe by the rearrangement of its atoms into a dataome. But there’s an even deeper perspective: Was all of this really inevitable? Did we ever have a choice in creating a dataome or doing any of the things we do, and does any self-aware entity in the universe have a choice either?

"In a wonderfully lively, and extraordinarily ideas-dense, near 70-page long 2013 essay titled “The Ghost in the Quantum Turing Machine,” the theoretical computer scientist Scott Aaronson goes deep in search of arguments for and against such free will. It’s such fun that I want to spend some time with it here. He points out that many of us conflate the idea of random unpredictability with free will. For example, I can feel like I’m exerting free will if I, well, I don’t know, spontaneously write the word “sponge” here. It certainly seems entirely random.

"That, Aaronson argues, is probably not right because what we call randomness actually follows well-defined statistical rules of probability, and in that sense is never “free.” Its unpredictability is predictable. By contrast there is a class of unpredictable phenomena that can’t be measured by random probabilities; they have a different form of unpredictability. This is described by a property called Knightian uncertainty after one Frank Knight, an economist working on these ideas in the 1920s. In modern vernacular this is very much like the “black swan event” idea popularized skillfully by the writer and mathematical thinker Nassim Taleb.

***

"...the knowable universe is big but decidedly finite. We can only ever observe the realm of the cosmos from which light has had time to reach us since the Big Bang some 13.8 billion years ago. This is tricky, but we can actually estimate the maximum number of any kind of bits (not just freebits) in the observable universe as approximately ten-to-the-power-of-122 (or 10122). The implication is that this is the limit of the number of interesting things that can ever happen in the universe. No do-overs, no extras, this is it.

"But this also means that freebits, and bits, are getting “used up” over time. Indeed, they must be for events to occur. And this brings us full-circle back to the classical physics ideas of the laws of thermodynamics and entropy, and the Landauer limit on energy needed to erase bits. Storing and accessing information means using energy. But if you use energy you have to maintain or increase the entropy of the cosmos (generally speaking). If there are a finite number of bits in all of reality, even if a huge number like 10122, then eventually the universe runs out of ways to change its entropy, and its bits.

"At this point the story connects to the far, far, far cosmic future in which everything is in thermal equilibrium: Space is at the same temperature, everywhere. There are no hot and cold spots, no ways for energy to flow from warm things to chilly things. No more bits to flip and the universe ends up as a tepid bath, full of nothing but regrets. (Although regrets imply information, and there would be no way to access that at this late stage).

"Is any of this a valid description of the world that has been and is to come? We don’t really know, although our best bet is that the ever-expanding universe is indeed heading to eventual boredom in thermal uniformity. Concepts like freebits are, for now, merely intriguing proposals about what makes reality tick under the surface.

"The essential point to all of this is that information shows itself to be more than one might expect. It isn’t just a way to probe the fundamentals of nature; it may be part of the fundamentals. Consequently, the fact that the human dataome is becoming increasingly entwined with the fabric of the universe—as pieces of manipulated matter and energy—means that we (as living things) are fully committed to the universal drive toward that future ocean of unchanging, equilibrated spacetime. It is as if we popped out of the vacuum as a temporary fluctuation of energy, and we’ve been clawing our way back ever since.

Comment: I've skipped lots of confusing points. The focus is that we are filling the universe with information, and the universe is based on information.

5321 views

No change in findings or theory:

https://science.sciencemag.org/content/372/6548/1301.7/tab-pdf

"Propagation of sound waves in the early Universe imprinted characteristic density fluctuations known as baryon acoustic oscillation (BAO). Galaxies preferentially form in higher-density regions, so BAO can be measured using galaxy redshift surveys. Alam et al. report the final cosmological parameters from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) both independently of other datasets and in combination with alternative cosmological techniques. The authors found strong support for standard cosmology with cold dark matter, a flat Universe, and dark energy described by a cosmological constant. The only notable inconsistency was the well-known tension in measurements of the Hubble constant, which persists in the new data."

Phys. Rev. D 103, 083533 (2021).

Comment: Does not alter any theories. And Hubble still won't behave

5310 views

Everything in the universe spins:

https://www.sciencenews.org/article/dark-matter-cosmic-filaments-biggest-spinning-objec...

"Moons do it, stars do it, even whole galaxies do it. Now, two teams of scientists say cosmic filaments do it, too. These tendrils stretching hundreds of millions of light-years spin, twirling like giant corkscrews.

"Cosmic filaments are the universe’s largest known structures and contain most of the universe’s mass (SN: 1/20/14). These dense, slender strands of dark matter and galaxies connect the cosmic web, channeling matter toward galaxy clusters at each strand’s end (SN: 7/5/12).

"At the instant of the Big Bang, matter didn’t rotate; then, as stars and galaxies formed, they began to spin. Until now, galaxy clusters were the largest structures known to rotate. “Conventional thinking on the subject said that’s where spin ends. You can’t really generate torques on larger scales,” says Noam Libeskind, cosmologist at the Leibniz Institute for Astrophysics Potsdam in Germany.

"So the discovery that filaments spin — at a scale that makes galaxies look like specks of dust — presents a puzzle. “We don’t have a full theory of how every galaxy comes to rotate, or every filament comes to rotate,” says Mark Neyrinck, cosmologist at University of the Basque Country in Bilbao, Spain.

***

"The two teams detected similar rotational velocities for filaments despite differing approaches, Neyrinck says, an “encouraging [indication] that we’re looking at the same thing.”

"Next, researchers want to tackle what makes these giant space structures spin, and how they get started. “What is that process?” Libeskind says. “Can we figure it out?'”

Comment: At least the cosmologists are like dhw, who wants to know why God so many strange things in making the universe. They will find a cause and probably a reason. God knows what He is doing even if dhw doesn't think so. For life the Earth's rotation seems necessary.

5318 views

Heat from their auroras do it:

https://www.realclearscience.com/2021/06/23/gas_giants_energy_crisis_solved_after_50_ye...

"Living as they do in the distant, sun-forsaken reaches of the solar system, Jupiter and Saturn, the gas giants, and Uranus and Neptune, the ice giants, were always expected to be frosty realms. But when NASA’s Voyager spacecraft sailed past them in the late 1970s and 1980s, scientists found that all four worlds were running planetary fevers — a revelation as jarring as finding a bonfire inside your freezer.

"Follow-up observations by ground-based telescopes and the Galileo and Cassini spacecraft demonstrated that their planet-wide fevers have persisted through time. Their planetary pyrexias are acute: Jupiter’s lower latitudes, for example, should be a frigid −110 degrees Celsius. Instead, the atmosphere there cooks at 325 degrees. What incognito incinerator is behind this? And how is this unknown heat source warming not just a single spot on the planet, but the entire upper atmosphere?

"Scientists have tried to explain this “energy crisis,” but have remained “confused for about 50 years,” said James O’Donoghue, a planetary astronomer at the Japan Aerospace Exploration Agency. Now two papers have conclusively revealed where all that heat is coming from: Jupiter and Saturn’s northern and southern lights — their auroras.

"The results come from detailed measurements of both gas giants’ upper atmospheres. Saturn’s atmospheric temperature was taken by the Cassini spacecraft during the maneuvers that ultimately plunged it into the planet; Jupiter’s was stitched together using a telescope atop a giant Hawaiian volcano. Both show that the atmospheres are hottest near the auroral zones below both magnetic poles. As you approach the equator, the temperature drops off. Clearly, the aurora is bringing the heat — and, as with a radiator, that heat decreases with distance."

Comment: the article goes at great length to explain auroras here and on Saturn and Jupiter. 'Hot' Uranus and Neptune are not yet explained. Bit by bit we explain all the universe's oddities.

5311 views

Finally identified, predicted 40 years ago:

https://www.sciencedaily.com/releases/2021/06/210628114136.htm

"A worldwide team led by UC Santa Barbara scientists at Las Cumbres Observatory has discovered the first convincing evidence for a new type of stellar explosion -- an electron-capture supernova. While they have been theorized for 40 years, real-world examples have been elusive. They are thought to arise from the explosions of massive super-asymptotic giant branch (SAGB) stars, for which there has also been scant evidence.

***

"Historically, supernovae have fallen into two main types: thermonuclear and iron-core collapse. A thermonuclear supernova is the explosion of a white dwarf star after it gains matter in a binary star system. These white dwarfs are the dense cores of ash that remain after a low-mass star (one up to about 8 times the mass of the sun) reaches the end of its life. An iron core-collapse supernova occurs when a massive star -- one more than about 10 times the mass of the sun -- runs out of nuclear fuel and its iron core collapses, creating a black hole or neutron star. Between these two main types of supernovae are electron-capture supernovae. These stars stop fusion when their cores are made of oxygen, neon and magnesium; they aren't massive enough to create iron.

"While gravity is always trying to crush a star, what keeps most stars from collapsing is either ongoing fusion or, in cores where fusion has stopped, the fact that you can't pack the atoms any tighter. In an electron capture supernova, some of the electrons in the oxygen-neon-magnesium core get smashed into their atomic nuclei in a process called electron capture. This removal of electrons causes the core of the star to buckle under its own weight and collapse, resulting in an electron-capture supernova.

"If the star had been slightly heavier, the core elements could have fused to create heavier elements, prolonging its life. So it is a kind of reverse Goldilocks situation: The star isn't light enough to escape its core collapsing, nor is it heavy enough to prolong its life and die later via different means.

"That's the theory that was formulated beginning in 1980 by Ken'ichi Nomoto of the University of Tokyo and others.

***

"The new discoveries also illuminate some mysteries of the most famous supernova of the past. In A.D. 1054 a supernova happened in the Milky Way Galaxy that, according to Chinese and Japanese records, was so bright that it could be seen in the daytime for 23 days, and at night for nearly two years. The resulting remnant, the Crab Nebula, has been studied in great detail.

"The Crab Nebula was previously the best candidate for an electron-capture supernova, but its status was uncertain partly because the explosion happened nearly a thousand years ago. The new result increases the confidence that the historic SN 1054 was an electron-capture supernova. It also explains why that supernova was relatively bright compared to the models: Its luminosity was probably artificially enhanced by the supernova ejecta colliding with material cast off by the progenitor star as was seen in SN 2018zd."

Comment: This discovery should reassure dhw not every event in the universe is especially designed by God. This event is an obviously natural result of His designs. Supernovas deliver the life-required elements needed for life by spreading them all over the galaxy and probably over the universe.

5301 views

Gravitational wave for that merger seen:

https://www.sciencenews.org/article/gravitational-waves-ligo-first-black-hole-neutron-s...

"Caught in a fatal inward spiral, a neutron star met its end when a black hole swallowed it whole. Gravitational ripples from that collision spread outward through the cosmos, eventually reaching Earth. The detection of those waves marks the first reported sighting of a black hole engulfing the dense remnant of dead star. And in a surprise twist, scientists spotted a second such merger just days after the first.

***

"The mismatched pairing of a black hole and neutron star was the final type of merger that scientists expected to find with current gravitational wave observatories. By pure coincidence, researchers spotted two of these events within 10 days of one another, the LIGO, Virgo and KAGRA collaborations report in the July 1 Astrophysical Journal Letters.

"Not only have unions between black holes and neutron stars not been seen before via gravitational waves, the smashups have also never been spotted at all by any other means.

***

"To form detectable gravitational waves, the objects that coalesce must be extremely dense, with identities that can be pinned down by their masses. Anything with a mass above five solar masses could only be a black hole, scientists think. Anything less than about three solar masses must be a neutron star.

***

"Epic rendezvous between neutron stars and black holes happen regularly throughout the cosmos, the detections suggest. Based on the pace of detections, the researchers estimate that these events take place about once a month within 1 billion light-years of Earth."

Comment: as dhw and I have agreed much of the happenings in the universe are at random, a result of initial design

5292 views

They come from far, far away and are not dangerous to us even though they are massive bursts of energy:

https://www.quantamagazine.org/brighter-than-a-billion-billion-suns-gamma-ray-bursts-co...

"...in 1997, an Italian and Dutch satellite called BeppoSAX confirmed that gamma-ray bursts were extragalactic, in some cases originating many billions of light-years away.

***

"A gamma-ray burst will emit the same amount of energy as a supernova, caused when a star collapses and explodes, but in seconds or minutes rather than weeks. Their peak luminosities can be 100 billion billion times that of our sun, and a billion times more than even the brightest supernovas.

"It turned out to be fortunate that they were so far away. “If there was a gamma-ray burst in our galaxy with a jet pointed at us, the best thing you could hope for is a quick extinction,” said Zhu. “You would hope that the radiation smashes through the ozone and immediately fries everything to death. Because the worst scenario is if it’s farther away, it could cause some of the nitrogen and oxygen in the atmosphere to turn into nitrous dioxide. The atmosphere would turn brown. It would be a slow death.”

"Gamma-ray bursts come in two flavors, long and short. The former, which can last up to several minutes or so, are thought to result from stars more than 20 times the mass of our sun collapsing into black holes and exploding as supernovas. The latter, which last only up to about a second, are caused by two merging neutron stars (or perhaps a neutron star merging with a black hole), which was confirmed in 2017 when gravitational-wave observatories detected a neutron star merger and NASA’s Fermi Gamma-ray Space Telescope caught the associated gamma-ray burst.

"In each instance, the gamma-ray burst does not come from the explosion itself. Rather it comes from a jet moving at a fraction below the speed of light that gets fired out from the explosion in opposite directions. (The exact mechanism that powers the jet remains a “very fundamental question,” said Zhu.)

“'It is that combination of the speed at high energy and the focusing into a jet that makes them extremely luminous,” said Nial Tanvir, an astronomer at the University of Leicester in England. “That means we can see them very far away.” On average, there is thought to be one observable gamma-ray burst in the visible universe every day.

***

Until recently, the only way to study gamma-ray bursts was to observe them from space, as "Earth’s ozone layer blocks gamma rays from reaching the surface. But as gamma rays enter our atmosphere, they bump into other particles. These particles get pushed faster than the speed of light in air, which leads them to emit a blue glow known as Cherenkov radiation. Scientists can then scan for these blue bursts of light.

"Because our atmosphere has a much larger collecting area than a single telescope, this search strategy gives astrophysicists a greater chance of finding the highest-energy gamma-ray bursts, which are rare and hard to spot.

"The first observation of such an ultrahigh-energy burst was made in July 2018 by an array of antennas in Namibia called the High Energy Stereoscopic System (HESS). The radiation came not from the initial gamma-ray burst itself, but from an effect called the afterglow. In this case, the gamma-ray burst’s jet collided with material thrown off from the star as it went supernova. The collision accelerated particles to high speeds, producing electromagnetic radiation that then made its way to Earth.

***

"Gamma-ray bursts and their afterglows can play an important role in our understanding of the universe too. Supernovas and neutron star mergers are thought to produce the universe’s heavy elements, such as gold and platinum. Since bursts give a window into the wreckage following these events, scientists can use them to track how the chemical composition of the universe has changed over cosmic time."

Comment: Another example of violent cosmos activity not directly affecting us now.

5317 views

Not really possible:

https://mindmatters.ai/2021/06/no-free-lunches-bernoulli-is-right-keynes-is-wrong/

"If nothing is known about the outcome of a random event, all outcomes can be assumed to be equally probable. Bernoulli’s Principle of Insufficient Reason (PrOIR) is commonly used.

https://mathworld.wolfram.com/PrincipleofInsufficientReason.html

"Principle of Insufficient Reason A principle that was first enunciated by Jakob Bernoulli which states that if we are ignorant of the ways an event can occur (and therefore have no reason to believe that one way will occur preferentially compared to another), the event will occur equally likely in any way.

***

"A common visualization of the classic Big Bang model starts with a big empty space where a type of explosion happens.

"No. This is wrong. “A big empty space” is something, and nothing existed before the Big Bang.

"With some imagination, the “big empty space” can be removed from the visualization. Often the next description, with the idea of space removed, is that suddenly there was an explosion. No. This doesn’t work either. “Suddenly” assumes time, and time is something. Nothing, including time, existed before the creation. (Biblical references to “In the beginning” and “before the beginning of time” are congruent.) So we are left with trying to understand Big Bang ex-nihilo creation void of space and time. Imagining the existence of nothing can be difficult. Doing so can tax the imagination.

"Hidden biases easily sneak in when dealing with either Bernoulli’s PrOIR or Big Bang creation."

Comment: The Big Bang created space-time reality. Its origin is as mysterious as God, Himself. We can not imagine the BB in any way as a start of what is now present. We cannot treat the BB as a natural event. It cannot be a quantum fluctuation, by definition of the above considerations. I am left with God, the Creator.

5286 views

There has to be some in the vacuum:

http://backreaction.blogspot.com/2021/07/can-we-make-new-universe.html

"Einstein also taught us that space is dynamic. It can bend and curve, and it can expand. It changes with time. And if space changes with time, then energy is not conserved. I explained this in more detail an earlier video, but here’s a brief summary.

"The simplest example of energy non-conservation is the cosmological constant. The cosmological constant is the reason that the expansion of our universe gets faster. It has units of an energy-density – so that’s energy per volume – and as the name says, it’s constant. But if the energy per volume is constant, and the volume increases, then the total energy increases with the volume. This means in an expanding universe, you can get a lot of energy from nothing – if you just manage to expand space rapidly enough. I know that this sounds completely crazy, but this is really how it works in Einstein’s theory of General Relativity. Energy is just not conserved.

***

"...no one really knows how our universe was created in the first place. There are many different theories for it, but none of them has observational support. However, one of those theories has become very popular among astrophysicists, it’s called “eternal inflation” – and while we don’t know it’s right, it could be right.

"In eternal inflation, our universe is created from the decay of a false vacuum. To understand what a false vacuum is, let’s first talk about what a true vacuum is. A true vacuum is in a state of minimal energy. You can’t get energy out of it, it’s stable. It just sits there. Because it already has minimal energy, it can’t do anything and you can’t do anything with it.

"A false vacuum is one that looks like a true vacuum temporarily, but eventually it decays into a true vacuum because it has energy left to spare, and that extra energy goes into something else. For example, if you throw jelly at a wall, it’ll stick there for a moment, but then fall down. That moment when it sticks to the wall is kind of like a false vacuum state. It’s unstable and it will eventually decay into the true vacuum, which is when the jelly drops to the ground and the extra energy splatters it all over the place.

***

"What does this have to do with the creation of our universe? Well, consider you have a lot of false vacuum. In that false vacuum, there’s a patch that decays into a true vacuum. The true vacuum has a lower energy, but it can have higher pressure. If it has higher pressure, it’ll expand. That’s is how our universe could have started. And in principle you can recreate this situation in the laboratory. You “just” have to create this false vacuum state. Then part of it will decay into a true vacuum. And if the conditions are right, that true vacuum will expand rapidly. While it expands it creates its own space. It does not grow into our universe, it makes a bubble."

Comment: This explains how our universe has 'dark energy' producing the expansion. All theory, as no one has found that energy for real

5282 views

The source of heavy elements discovered from very special stars:

https://www.sciencenews.org/article/star-explosion-hypernova-supernova-universe-heavy-e...

"Violent explosions of massive, magnetized stars may forge most of the universe’s heavy elements, such as silver and uranium.

"These r-process elements, which include half of all elements heavier than iron, are also produced when neutron stars merge. But collisions of those dead stars alone can’t form all of the r-process elements seen in the universe. Now, scientists have pinpointed a type of energetic supernova called a magnetorotational hypernova as another potential birthplace of these elements.

"The results, described July 7 in Nature, stem from the discovery of an elderly red giant star — possibly 13 billion years old — in the Milky Way’s halo. By analyzing the star’s elemental makeup, which is like a star’s genetic instruction book, astronomers peered back into the star’s family history. Forty-four different elements seen in the star suggest that it was formed from material left over “by a special explosion of one massive star soon after the Big Bang,” says astronomer David Yong of the Australian National University in Canberra.

***

"The researchers think that magnetorotational hypernovas are rare, composing only 1 in 1,000 supernovas. Even so, such explosions would be 10 times as common as neutron star mergers today, and would produce similar amounts of heavy elements per event. Along with their less energetic counterparts, called magnetorotational supernovas, these hypernovas could be responsible for creating 90 percent of all r-process elements, coauthor Chiaki Kobayashi, an astrophysicist at the University of Hertfordshire in Hatfield, England, had previously calculated. In the early universe, when massive, rapidly rotating stars were more common, such explosions could have been even more influential."

Comment: The theory that Earth received its elements by ancient star explosions is not new. But the known process only covered lighter elements. This opens up the possibilities for the heavier ones. The oddball activities in the universe, for which dhw wonders about for God's reasons, all haver purpose. Just wait for research to explain. Just because we don't know all the answers is no reason for doubt.

5257 views

Other possibilities of topology are considered:

https://www.forbes.com/sites/startswithabang/2021/07/21/why-the-universe-probably-isnt-...

"The true problem with the Universe is that there’s only one to observe, or at least, only one that we’re capable of observing. We don’t have a large sample of Universes to compare between, and we don’t have a large set of data points available to us within our Universe. It’s like rolling five dice, together, once. Your odds of getting all sixes is small: about 1-in-7800. Yet if you rolled five dice at once and saw that it came up all sixes, you wouldn’t necessarily conclude that it was anything more than random chance. Sometimes, nature just doesn’t give you the most likely outcome.

"It’s possible that the leftover photons from the Big Bang, reaching us today as a snapshot from 13.8 billion years ago, really are the result of expanding from a donut-shaped Universe, one that’s barely larger than the observational limits of what we perceive today. But the one piece of evidence we have to support that scenario isn’t particularly compelling, and cannot rule out the null hypothesis: that we live in a Universe indistinguishable from flat, simply connected, and without any fancy topological traits. Unless we find a way to extract more information from our Universe — and we’ve already pulled everything out of the cosmic microwave background that we can, to the limits of our observations — we may never be able to meaningfully discriminate between these two possibilities."

Comment: This is an enormous theoretical article basically disputing all theories but a flat universe, By Ethan Siegel, at Forbes, an Ph.D. astrophysicist, author, and science communicator, who professes physics and astronomy at various colleges.

5245 views

Hosssenfelder at her best:

http://backreaction.blogspot.com/2021/07/can-physics-be-too-speculative.html

"The question we are facing, thus, is similar to the one that the philosopher Imre Lakatos posed: Which research programs make progress, and which have become degenerative? When speculation stimulates progress it benefits science, but when speculation leads to no insights for the description of nature, it eats up time and resources, and gets in the way of progress. Which research program is on which side must be assessed on a case-by-case basis.

"Dark matter is an example of a research program that used to be progressive but has become degenerative. In its original form, dark matter was a simple parameterization that fit a lot of observations – a paradigmatic example of a good scientific hypothesis. However, as David Merritt elucidates in his recent book “A philosophical approach to MOND”, dark matter has trouble with more recent observations, and physicists in the area have taken on to accommodating data, rather than making successful predictions.

"Moreover, the abundance of specific particle models for dark matter that physicists have put forward are unnecessary to explain any existing observations. These models produce publications but they do not further progress. This isn’t so surprising because guessing a specific particle from rather unspecific observations of its gravitational pull has an infinitesimal chance of working.

"Theories for the early universe or fifth forces suffer from a similar problem. They do not explain any existing observations. Instead, they make the existing – very well working – theories more complicated without solving any problem.

"String theory is a different case. That’s because string theory is supposed to remove an inconsistency in the foundations of physics: The missing quantization of gravity. If successful, that would be progress in and by itself, even if it doesn’t result in testable predictions. But string theorists have pretty much given up on their original goal and never satisfactorily showed the theory solves the problem to begin with.

"Moreover, the abundance of specific particle models for dark matter that physicists have put forward are unnecessary to explain any existing observations. These models produce publications but they do not further progress. This isn’t so surprising because guessing a specific particle from rather unspecific observations of its gravitational pull has an infinitesimal chance of working.

"Theories for the early universe or fifth forces suffer from a similar problem. They do not explain any existing observations. Instead, they make the existing – very well working – theories more complicated without solving any problem.

"String theory is a different case. That’s because string theory is supposed to remove an inconsistency in the foundations of physics: The missing quantization of gravity. If successful, that would be progress in and by itself, even if it doesn’t result in testable predictions. But string theorists have pretty much given up on their original goal and never satisfactorily showed the theory solves the problem to begin with."

Comment: The lesson here is some grant programs can't be killed. String theory has veered off into something else, but strings are not progressing to anything substantive. Wec can onl learn abaout God's works if we reveal substantive material.

5234 views

It requires enormous energy to see it:

https://www.sciencedaily.com/releases/2021/08/210806104328.htm

"In the early stages of the Universe, quarks and gluons were quickly confined to protons and neutrons which went on to form atoms. With particle accelerators reaching increasingly higher energy levels the opportunity to study this fleeting primordial state of matter has finally arrived.

"Quark-Gluon Plasma (QGP) is a state of matter which existed only for the briefest of times at the very beginning of the Universe with these particles being quickly clumped together to form the protons and neutrons that make up the everyday matter that surrounds us. The challenge of understanding this primordial state of matter falls to physicists operating the world's most powerful particle accelerators.

***

"'Quark-Gluon Plasma is the strongly interacting deconfined matter which existed only briefly in the early universe, a few microseconds after the Big Bang," says Mustafa. "The discovery and characterisation of the properties of QGP remain some of the best orchestrated international efforts in modern nuclear physics." Mustafa highlights Heavy Ion Phenomenology as providing a very reliable tool to determine the properties of QGP and in particular, the dynamics of its evolution and cooling.

"Improvements at colliders such as the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) have radically increased the energy levels that can be attained by heavy nuclei collisions at near-light speeds bringing them in line with those of the infant Universe. In addition to this, future experiments at the Facility for Antiproton and Ion Research (FAIR) and at the Nuclotron-based Ion Collider fAcility (NICA) will generate a wealth of data on QGP and the conditions in the early Universe.

"'This collection is so timely as it calls for a better theoretical understanding of particle properties of hot and dense deconfined matter, which reflect both static and dynamical properties of QGP," explains Mustafa. "This improved theoretical understanding of Quark-Gluon Plasma and Heavy Ion Phenomenology is essential for uncovering the properties of the putative QGP which occupied the entire universe, a few microseconds after Big Bang."

"Mustafa points out that this improved understanding should also open the doorway to understanding the equation of state of this strongly interacting matter and prepare the platform to explore the theory of quark-hadron transition and the possible thermalisation of the QGP. This could in turn help us understand the steps that led from QGP to the everyday baryonic matter that surrounds us.

"'The quarks and gluons which formed the neutrons and protons were confined into them, a few microseconds after the Big Bang," concludes Mustafa. "This is the first time when we have seen them being liberated from their eternal confinement!'"

Comment: If there was nothing before the BB, where did the enormous energy come from? In considering God as the alternative, we must assume He could create such energy. We can't get something from nothing.

5128 views

Brief report:

https://www.newscientist.com/article/2287047-astronomers-may-have-spotted-a-new-spiral-...

Astronomers may have found part of a never-before-seen arm of the Milky Way galaxy. This huge stream of gas – named Cattail because of its long, thin shape – is the largest and most distant gas filament ever spotted in our galaxy.

Keping Qiu at Nanjing University in China and his colleagues found one end of Cattail using the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in China. They then searched data from the HI4PI survey, an all-sky search for hydrogen gas, …

Comment: All I can copy. Not a surprise finding.

5105 views

The sun seems to contain more metals than other stars produce:

https://www.sciencedaily.com/releases/2021/09/210908180617.htm

"Galaxies are made up of a collection of stars and are formed by the condensation of the gas of the intergalactic medium composed of mostly hydrogen and a bit of helium. This gas does not contain metals unlike the gas in galaxies -- in astronomy, all chemical elements heavier than helium are collectively called "metals," although they are atoms in gaseous form..... When a star that has reached the end of its life explodes, it expels the metals it has produced, such as iron, zinc, carbon and silicon, feeding these elements into the gas of the galaxy. These atoms can then condense into dust, especially in the colder, denser parts of the galaxy. "Initially, when the Milky Way was formed, more than 10 billion years ago, it had no metals. Then the stars gradually enriched the environment with the metals they produced," continues the researcher. When the amount of metals in this gas reaches the level that is present in the Sun, astronomers speak of Solar metallicity.

***

"Thanks to this dual observation technique, the astronomers have found that not only is the Milky Way's environment not homogeneous, but that some of the areas studied reach only 10% of the Solar metallicity. "This discovery plays a key role in the design of theoretical models on the formation and evolution of galaxies," says Jens-Kristian Krogager, researcher at the UNIGE's Department of Astronomy. "From now on, we will have to refine the simulations by increasing the resolution, so that we can include these changes in metallicity at different locations in the Milky Way."

"These results have a strong impact on our understanding of the evolution of galaxies and of our own in particular. Indeed, metals play a fundamental role in the formation of stars, cosmic dust, molecules and planets. And we now know that new stars and planets could be formed today from gases with very different compositions."

Comment: our sun produces the necessary elements we need to support evolution and our lives. This study shows how special it is and in my mind adds to the fine-tuning argument for the existence of God.

5021 views

Latest findings fit inflation theory:

https://phys.org/news/2021-10-latest-results-cosmic-microwave-background.html

"The universe was created about 13.8 billion years ago in a blaze of light: the big bang. Roughly 380,000 years later, after matter (mostly hydrogen) had cooled enough for neutral atoms to form, light was able to traverse space freely. That light, the cosmic microwave background (CMB) radiation, comes to us from every direction in the sky uniformly ... or so it first seemed. In the last decades astronomers have discovered that the radiation has faint ripples and bumps in it at a level of brightness of only a part in one hundred thousand—the seeds for future structures, like galaxies.

"Astronomers have conjectured that these ripples also contain traces of an initial burst of expansion—the so-called inflation—which swelled the new universe by thirty-three orders of magnitude in a mere ten-to-the-power-minus-33 seconds. Clues about the inflation should be faintly present in the way the cosmic ripples are curled, an effect due to gravitational waves in cosmic infancy that is expected to be perhaps one hundred times or more fainter than the ripples themselves.

"The curling effect produces patterns in the light known as "B-mode polarization," and it is expected to be exceedingly faint. Other exotic processes are at work in the universe to make this daunting measurement even more challenging. The principal one is the faint glow of light from dust particles in our galaxy that have been aligned by magnetic fields. This light is also polarized and can be twisted by magnetic fields to produce B-mode polarization patterns. Radio waves from our galaxy can produce similar effects. About six years ago, CfA astronomers working at the South Pole reported the first evidence for such curling, "B-mode polarization," at levels consistent with simple models of inflation, but subsequent measurements at different frequencies (or colors) of microwave light revealed the signal to be explainable by galactic dust.

***

"The new results improve the previous best constraints on curling by about a factor of two, and now provide powerful guidance on the kinds of models of inflation that could describe the earliest moments of the universe.

"A broad class of simple models is now largely ruled out. The team reports that the most favored of the remaining class of models predict primordial gravitational waves at levels that should be detected (or ruled out) within the next decade with upgraded telescopes at the South Pole. The team is already in the process of upgrading the BICEP system and expects to gain another factor of about three improvements within five years, enough to set tight constraints to inflationary models."

Comment: the CMB is still revealing secrets about the early universe and still supports inflationary theory.

4979 views

It could be part of a cycle of beginnings or not:

https://evolutionnews.org/2021/10/attempt-to-explain-away-the-beginning-of-the-universe...

"Here I will address another desperate attempt to avoid a cosmic beginning, this one by astrophysicist Paul Sutter. He is a research professor at the Institute for Advanced Computational Science at Stony Brook University and the Flatiron Institute in New York City. He recently published at the website Live Science an article titled “What if the universe had no beginning?” Sutter argues that a cosmological model based on causal set theory demonstrates that the universe might not have had a beginning. His argument upon close inspection also collapses.

***

"Sutter references a preprint article employing CSC by physicists Bruno Valeixo Bento and Stav Zalel titled “If time had no beginning.” He summarizes their work as follows:

"The paper examined “whether a beginning must exist in the causal set approach,” Bento said. “In the original causal set formulation and dynamics, classically speaking, a causal set grows from nothing into the universe we see today. In our work instead, there would be no Big Bang as a beginning, as the causal set would be infinite to the past, and so there’s always something before.”

…"Their work implies that the universe may have had no beginning — that it has simply always existed. What we perceive as the Big Bang may have been just a particular moment in the evolution of this always-existing causal set, not a true beginning.

"Confusing Imagination with Reality
Sutter asserts that Bento and Zalel’s article offers a credible response against the evidence for a cosmic beginning. Yet this claim is only based on what might be possible in the realm of the imagination. The referenced paper is a highly theoretical and entirely speculative cosmological model that is almost entirely divorced from physical reality. Sutter even acknowledges this point:

"There’s still a lot of work to be done, however. It’s not clear yet if this no-beginning causal approach can allow for physical theories that we can work with to describe the complex evolution of the universe during the Big Bang.

"His claiming that Bento and Zalel’s paper represents a credible refutation of a cosmic beginning is like a journalist interviewing a scientist who imagines a new possible rocket fuel and then claiming that the scientist demonstrated how NASA could establish permanent colonies on Pluto. Such sensationalist reporting is deeply irresponsible.

"Moreover, even if a mature version of CSC eventually described the Big Bang, it would not avoid a cosmic beginning. Proponents of CSC could assume an oscillating universe where Big Bang events correspond to a contraction stage transitioning according to causal-set dynamics to an expansion stage. In such a case, CSC is only needed to describe the bounces. Both the contractions and expansions would follow standard cosmological models for oscillating universes. Stephen Meyer explained in his book why an oscillating universe still requires an absolute beginning.

"Specifically, Meyer summarized how cosmologist Alan Guth demonstrated that the oscillations could not continue indefinitely due to entropy:

"Guth showed that, according to the second law, the entropy (or disorder) of the matter and energy in the universe would increase over time in each cycle. But such increases in entropy (or the disorderly distribution of mass-energy) would result in less energy available to do work in each cycle. That would cause progressively longer and longer cycles of expansion and contraction, since increasing inhomogeneities in the mass-energy density throughout space would decrease the efficiency of gravitational contraction. Yet if the duration of each cycle necessarily increases as the universe moves forward in time, then it follows that each cycle in the past would have been progressively shorter. Since the periods of each cycle cannot decrease indefinitely, the universe — even in an oscillating model — would have had to have a beginning."

Comment: Guth's point cannot be avoided that a cyclical process would eventually run down. None of this discusses the geometry of space which is flat, and that says there is an end to this expansion as a true end, no cycle.

4891 views

QUOTES: “In our work instead, there would be no Big Bang as a beginning, as the causal set would be infinite to the past, and so there’s always something before.”

…"Their work implies that the universe may have had no beginning — that it has simply always existed. What we perceive as the Big Bang may have been just a particular moment in the evolution of this always-existing causal set, not a true beginning.

"Confusing Imagination with Reality
Sutter asserts that Bento and Zalel’s article offers a credible response against the evidence for a cosmic beginning. Yet this claim is only based on what might be possible in the realm of the imagination. The referenced paper is a highly theoretical and entirely speculative cosmological model that is almost entirely divorced from physical reality. Sutter even acknowledges this point…

Of course it’s imagination. And so is the theory that a universe can spring from nothing, and so is the theory that a sourceless universal mind has occupied an eternal “before” and created the universe out of its immaterial self. Nobody can prove anything about what happened before the big bang, if the big bang happened! This discussion encourages pots to call kettles black!

4877 views

dhw: QUOTES: “In our work instead, there would be no Big Bang as a beginning, as the causal set would be infinite to the past, and so there’s always something before.”

…"Their work implies that the universe may have had no beginning — that it has simply always existed. What we perceive as the Big Bang may have been just a particular moment in the evolution of this always-existing causal set, not a true beginning.

"Confusing Imagination with Reality
Sutter asserts that Bento and Zalel’s article offers a credible response against the evidence for a cosmic beginning. Yet this claim is only based on what might be possible in the realm of the imagination. The referenced paper is a highly theoretical and entirely speculative cosmological model that is almost entirely divorced from physical reality. Sutter even acknowledges this point…

Of course it’s imagination. And so is the theory that a universe can spring from nothing, and so is the theory that a sourceless universal mind has occupied an eternal “before” and created the universe out of its immaterial self. Nobody can prove anything about what happened before the big bang, if the big bang happened! This discussion encourages pots to call kettles black!

Something happened since we are here instead of nothing.

4867 views

Still not settled but favors uniform distribution of galaxies:

https://www.realclearscience.com/2021/12/14/cosmologists_parry_attacks_on_cosmological_...

"Lopez’s “Giant Arc” seemed to clash with an idea that has guided astronomy for centuries: that the universe has no conspicuous features. From a zoomed-out perspective, no matter where you are or which way you look, you should see roughly the same number of galaxies pinwheeling around.

"This assumption, enshrined as the “cosmological principle,” has let researchers draw sweeping conclusions about the whole universe based only on what we see from our corner of it.

“'If that turns out to be wrong, then we have to redo many of our measurements or reinterpret many of our measurements,” said Ruth Durrer, a cosmologist at the University of Geneva.

"As a load-bearing strut of modern cosmology, the cosmological principle has increasingly become a target. Some challengers, like Lopez and her colleagues, are astrophysicists puzzled by striking celestial conglomerations. Others are maverick cosmologists unsettled by the consensus view that most of the stuff in the cosmos hides from our instruments in the form of “dark matter” and “dark energy”; they wonder whether theorists may have conjured phantasms to patch up an overly simplistic theory of cosmology.

"Most everyone agrees that the cosmological principle is worth scrutinizing. So far, though, each new claim of a too-big structure or other anomaly has failed to make a dent. We are “trying to poke as many holes as we can,” said Seshadri Nadathur, a cosmologist at University College London, “while being very skeptical of someone else saying they’ve poked a hole.”

"Not only is Earth not special, but nothing anywhere is special. Over the past century, astronomical surveys solidified what’s become known as the cosmological principle in two ways. As powerful telescopes peered deeper into the darkness, they saw more-distant galaxies appearing in similar numbers. This suggests that the cosmos is homogeneous, with matter sprinkled smoothly throughout. (Think of the expanding universe as a rising fruitcake with galaxies evenly spread like fruit pieces, each one flying away from its neighbors as the batter between them expands.)

"Moreover, telescopes pointed in different directions have all seen similar scenes. Matter is evenly distributed along every line of sight, indicating that the universe is “isotropic.”

***

"The universe is clearly not homogeneous on the human scale. Teleport a person one light-year from here and you’ll ruin their day. But drop the Hubble Space Telescope halfway across the universe, and it will return familiar-looking galaxy-filled images. In this way, the cosmological principle treats the cosmos like the air in an inflating balloon. Up close, molecules mingle in complicated ways. But from far away, a bland gas expands with bulk properties like pressure and temperature changing steadily.

"Galaxy surveys have found that any patch of space larger than hundreds of millions of light-years across includes roughly the same amount of matter. So structures like the Giant Arc, which spans billions of light years, are as unexpected as a thick clot of air in an otherwise ordinary balloon.

***

"Strong evidence against any sort of cosmic flow comes from the afterglow of the Big Bang. Astronomers have determined that this “cosmic microwave background” (CMB) has an essentially identical average temperature of 2.725 degrees above absolute zero in every direction.

***

"Making grand inferences about the entire cosmos is hard because we are, after all, in a unique location: the here and now. Telescopes can only see so far, making it look as if galaxies peter out toward the limits of their vision. And as astronomers peer farther away and deeper into the past, they see galaxies in the early universe acting differently than they do today. Artifacts of our singular perspective are all too easily mistaken for failures of the cosmological principle itself.

“'Almost every effect that can screw you up works in that way,” Howell said. “It’s all because we only have one vantage point to look from in the universe.'”

Comment: I omitted much contrary 'evidence' which has convinced no one it is lumpy.

4603 views

Conflict not resolved:

https://www.nationalgeographic.com/science/article/the-universe-is-expanding-faster-tha...

"It’s one of the biggest puzzles in modern astronomy: Based on multiple observations of stars and galaxies, the universe seems to be flying apart faster than our best models of the cosmos predict it should. Evidence of this conundrum has been accumulating for years, causing some researchers to call it a looming crisis in cosmology.

"Now a group of researchers using the Hubble Space Telescope has compiled a massive new dataset, and they’ve found a-million-to-one odds that the discrepancy is a statistical fluke. In other words, it’s looking even more likely that there’s some fundamental ingredient of the cosmos—or some unexpected effect of the known ingredients—that astronomers have yet to pin down.

***

"Researchers have tried to measure the universe’s current rate of expansion in two primary ways: by measuring distances to nearby stars, and by mapping a faint glow dating back to the infant universe. These dual approaches provide a way to test our understanding of the universe across more than 13 billion years of cosmic history. The research has also uncovered some key cosmic ingredients, such as “dark energy,” the mysterious force thought to be driving the universe’s accelerating expansion.

"But these two methods disagree on the universe’s current expansion rate by about 8 percent. That difference might not sound like much, but if this discrepancy is real, it means the universe is now expanding faster than even dark energy can explain—implying some breakdown in our accounting of the cosmos.

"The researchers’ findings, described in several studies submitted last week to The Astrophysical Journal, use specific types of stars and stellar explosions to measure the distance between us and nearby galaxies. The dataset includes observations of 42 different stellar explosions, more than double the next-biggest analysis of its kind. According to the team’s work, the tension between their new analysis and results from measurements of the early cosmos has reached five sigma, the statistical threshold used in particle physics to confirm the existence of new particles."

Comment: this is an astronomy problem, but doesn't negate that the universe is in constant expansion. Apparently since the origin expansion is an unexplained requirement.

4550 views

Another review:

https://www.sciencealert.com/how-did-the-big-bang-explode-out-of-nothing-this-could-be-...

"...let's take a look at how "material" – physical matter – first came about. If we are aiming to explain the origins of stable matter made of atoms or molecules, there was certainly none of that around at the Big Bang – nor for hundreds of thousands of years afterwards.

"We do in fact have a pretty detailed understanding of how the first atoms formed out of simpler particles once conditions cooled down enough for complex matter to be stable, and how these atoms were later fused into heavier elements inside stars. But that understanding doesn't address the question of whether something came from nothing.

"So let's think further back. The first long-lived matter particles of any kind were protons and neutrons, which together make up the atomic nucleus. These came into existence around one ten-thousandth of a second after the Big Bang.

***

"The philosopher David Albert has memorably criticized accounts of the Big Bang which promise to get something from nothing in this way.

"Suppose we ask: where did spacetime itself arise from? Then we can go on turning the clock yet further back, into the truly ancient "Planck epoch" – a period so early in the Universe's history that our best theories of physics break down.

"This era occurred only one ten-millionth of a trillionth of a trillionth of a trillionth of a second after the Big Bang. At this point, space and time themselves became subject to quantum fluctuations.

"Physicists ordinarily work separately with quantum mechanics, which rules the microworld of particles, and with general relativity, which applies on large, cosmic scales. But to truly understand the Planck epoch, we need a complete theory of quantum gravity, merging the two.

***

"To truly answer the question of how something could arise from nothing, we would need to explain the quantum state of the entire Universe at the beginning of the Planck epoch.

"All attempts to do this remain highly speculative. Some of them appeal to supernatural forces like a designer. But other candidate explanations remain within the realm of physics – such as a multiverse, which contains an infinite number of parallel universes, or cyclical models of the Universe, being born and reborn again.

"The 2020 Nobel Prize-winning physicist Roger Penrose has proposed one intriguing but controversial model for a cyclical Universe dubbed "conformal cyclic cosmology".

***

"Conformal cyclic cosmology offers some detailed, albeit speculative, answers to the question of where our Big Bang came from. But even if Penrose's vision is vindicated by the future progress of cosmology, we might think that we still wouldn't have answered a deeper philosophical question – a question about where physical reality itself came from.

How did the whole system of cycles come about? Then we finally end up with the pure question of why there is something rather than nothing – one of the biggest questions of metaphysics.

***

"Endless new cycles are key to Penrose's own vision. But there is a natural way to convert conformal cyclic cosmology from a multi-cycle to a one-cycle form. Then physical reality consists in a single cycling around through the Big Bang to a maximally empty state in the far future – and then around again to the very same Big Bang, giving rise to the very same universe all over again.

"This latter possibility is consistent with another interpretation of quantum mechanics, dubbed the many-worlds interpretation. The many-worlds interpretation tells us that each time we measure a system that is in superposition, this measurement doesn't randomly select a state. Instead, the measurement result we see is just one possibility – the one that plays out in our own Universe."

Comment: lots of discussion going nowhere. We either really have something from nothing or we are back to Einstein looking for something eternal, but that is not an answer. What is first cause?

4520 views

And we don't know why:

https://www.newscientist.com/article/2280743-enormous-strands-of-galaxies-in-the-cosmic...

"Some of the largest structures in the universe appear to be rotating. The filaments of galaxies forming the cosmic web that stretches between galaxy clusters seem to be spinning, which could help us figure out why galaxies themselves – and everything else in space – rotate.

"How rotation is generated in space is a long-standing problem in astrophysics. “Not only are the galaxies spinning, but also the stars within the galaxies, and the Earth is spinning, and the Earth around the sun and the moon around the Earth. Pretty much the whole universe is spinning,” says Noam Libeskind at the Leibniz Institute for Astrophysics Potsdam in Germany. “We don’t really know why, and one way to try to answer that is to figure out where the spinning stops.”

"We cannot measure rotation directly on such large scales, so the researchers looked for patterns in the galaxies moving towards or away from Earth. When most of the galaxies on one side of a filament were moving away from us and most on the other were coming towards us, that indicated that the whole filament was rotating. Some of these gigantic strands of galaxies were spinning at nearly 100 kilometres per second.

"As the galaxies orbited the centres of their filaments, they also fell towards the galaxy clusters that mark the ends of each strand. “These galaxies are moving on these corkscrew-like, helical orbits,” says Libeskind. The filaments that ended at more massive clumps of galaxies seemed to rotate faster, but it isn’t yet clear why. More work will be required to answer that question, as well as the question of how the filaments’ rotation affects the spins of the galaxies themselves."

Comment: we know our Earth needs to spin so perhaps everything must in a universe fine-tuned for life

4508 views

At trillions of degrees of heat:

https://phys.org/news/2022-01-exotic-particles-quark-gluon-plasma.html

"In the first millionths of a second after the Big Bang, the universe was a roiling, trillion-degree plasma of quarks and gluons—elementary particles that briefly glommed together in countless combinations before cooling and settling into more stable configurations to make the neutrons and protons of ordinary matter.

"In the chaos before cooling, a fraction of these quarks and gluons collided randomly to form short-lived "X" particles, so named for their mysterious, unknown structures. Today, X particles are extremely rare, though physicists have theorized that they may be created in particle accelerators through quark coalescence, where high-energy collisions can generate similar flashes of quark-gluon plasma.

"Now physicists at MIT's Laboratory for Nuclear Science and elsewhere have found evidence of X particles in the quark-gluon plasma produced in the Large Hadron Collider (LHC) at CERN, the European Organization for Nuclear Research, based near Geneva, Switzerland.

"The team used machine-learning techniques to sift through more than 13 billion heavy ion collisions, each of which produced tens of thousands of charged particles. Amid this ultradense, high-energy particle soup, the researchers were able to tease out about 100 X particles, of a type known as X (3872), named for the particle's estimated mass."

Comment: I am not a physicist studying cosmology and the circumstances of the Big Bang. That quark-gluon plasma made up all of the matter of the eventual universe and contained enormous heat. From nothing? Not likely. The physicists act as if they really believe the hot Big Bang is real if they run experiments mimicking it. Guth et. al. proved to all at Hawkins' 60th birthday party celebration the BB had no past, so it had a mysterious start. God or ?.

4414 views

At the LHC:

https://www.livescience.com/x-particle-spotted-inside-lhc?utm_source=SmartBrief&utm...

"Physicists at the world's largest atom smasher have detected a mysterious, primordial particle from the dawn of time.

"About 100 of the short-lived "X" particles — so named because of their unknown structures — were spotted for the first time amid trillions of other particles inside the Large Hadron Collider (LHC), the world's largest particle accelerator, located near Geneva at CERN (the European Organization for Nuclear Research).

"These X particles, which likely existed in the tiniest fractions of a second after the Big Bang, were detected inside a roiling broth of elementary particles called a quark-gluon plasma, formed in the LHC by smashing together lead ions. By studying the primordial X particles in more detail, scientists hope to build the most accurate picture yet of the origins of the universe. They published their findings Jan. 19 in the journal Physical Review Letters."

Comment: There are lots to be still found.

4395 views

Departure from current theory with new far distant spiral galaxy studies:

https://phys.org/news/2022-02-distant-galaxies-true-nature-dark.html

"At the center of spiral galaxies—those near to us but also those billions of light-years away—there is a vast spherical region made up of dark matter particles. This region has two defining characteristics: a density that is constant out to a certain radius that amazingly expands over time, while the density decreases. This suggests the existence of a direct interaction between the elementary particles that make up the dark matter halo and those that make up ordinary matter—protons, electrons, neutrons, and photons. We anticipate that this hypothesis is in direct conflict with the current prevailing theory used to describe the universe—known as Lambda-Cold Dark Matter—which posits that particles of cold dark matter are inert and do not interact with any other particle except gravitationally.

***

"Dark matter makes up approximately 84% of the mass in the cosmos: "Its dominant presence throughout the galaxies arises from the fact that the stars and hydrogen gas are moving as if governed by an invisible element" explains Gauri Sharma. Up until now, attempts to study it have focused on galaxies near to our own: "In this study, however," she explains, "for the first time, we were seeking to observe and determine the distribution of the mass of spiral galaxies with the same morphology of those nearby, but much further away and therefore earlier by some seven billion years. The idea is essentially that these progenitors of spiral galaxies like our own could offer fundamental clues into the nature of the particle at the heart of the mystery of dark matter." Paolo Salucci adds that "by studying the movement of stars in approximately 300 distant galaxies, we discovered that these objects also had a halo of dark matter, and that, by starting out from the center of a galaxy, this halo effectively has a region in which its density is constant." This trait had already been observed in studies examining nearby galaxies, some of which were also the work of SISSA.

"The new research has revealed, however, that this central region had something that was wholly unexpected within the context of the so-called "standard model of cosmology." Sharma says that "as a result of the contrast between the properties of nearby and distant spiral galaxies—that is, between today's galaxies and their forebears from seven billion years earlier, we could see that not only is there an unexplained region with a constant density of dark matter, but also that its dimensions increase over time as if being subjected to a process of ongoing expansion and dilution." This evidence is very difficult to be explained if the dark matter particles did not interact, as posited in the Lambda-CDM model. "In the research we recently published," says Sharma, "we offer evidence of direct interaction between dark matter and ordinary matter, that over time slowly builds up a region of consistent density from the center of the galaxy outwards." But there's more.

"'Amazingly, the above region with constant density expands over time. It's a very slow process, but one that is inexorable" states Salucci. One possible explanation? "The simplest is that, in the beginning, when the galaxy was formed, the distribution of dark matter in the spherical halo was as predicted by the Lambda-CDM theory, with a density peak in the center. Later on, the galactic disc that characterizes spiral galaxies is formed, surrounded by a halo of extremely dense dark matter particles. As time passed, the effect of the interaction that we have posited meant that the particles were captured by the stars or expelled into the outer reaches of the galaxy." This process would create a spherical region of consistent density within the dark matter halo, with dimensions that increase proportionately over time and finally reach those of the galactic stellar disc, as described in the article in Astronomy and Astrophysics. "The results of the study pose important questions for alternative scenarios that describe dark matter particles (aside from Lambda-CDM), such as Warm Dark Matter, Self-Interacting Dark Matter and Ultra Light Dark Matter" says Sharma."

Comment: another step in trying to understand dark matter. The universe is vast, dangerous to life, yet because of the way it is built, we are here. dhw in the past has questioned why God made it that way. We are trying to find out. I don't know the answer, but currently simply assume that is what God needed to do. God must know what has to be done to achieve His purposes, but He doesn't tell us why, making it a challenge for us to discover, if we can. That is the difference between us. I accept God and His works as is/are and dhw tries to analyze everything about God using his (dhw's) human logic. The problem is God is not human and what He appears to have done may not make sense to us until we find the explanation. In the human body, so-called vestigial parts, like the appendix, are now shown to have very important roles. The lesson: don't judge God from our current ignorance. Can dhw learn? I would expect so.

4373 views

From Gaia telescope:

https://cfa.harvard.edu/news/1000-light-year-wide-bubble-surrounding-earth-source-all-n...

"The Earth sits in a 1,000-light-year-wide void surrounded by thousands of young stars — but how did those stars form?

***

"The paper's central figure, a 3D spacetime animation, reveals that all young stars and star-forming regions — within 500 light years of Earth — sit on the surface of a giant bubble known as the Local Bubble. While astronomers have known of its existence for decades, scientists can now see and understand the Local Bubble's beginnings and its impact on the gas around it.

"Using a trove of new data and data science techniques, the spacetime animation shows how a series of supernovae that first went off 14 million years ago, pushed interstellar gas outwards, creating a bubble-like structure with a surface that's ripe for star formation.

"Today, seven well-known star-forming regions or molecular clouds — dense regions in space where stars can form — sit on the surface of the bubble.

"'We've calculated that about 15 supernovae have gone off over millions of years to form the Local Bubble that we see today," says Zucker who is now a NASA Hubble Fellow at STScI.

***

"The expansion speed of the bubble, as well as the past and present trajectories of the young stars forming on its surface, were derived using data obtained by Gaia, a space-based observatory launched by the European Space Agency.

***

"'When the first supernovae that created the Local Bubble went off, our Sun was far away from the action," says co-author João Alves, a professor at the University of Vienna. "But about five million years ago, the Sun's path through the galaxy took it right into the bubble, and now the Sun sits — just by luck — almost right in the bubble's center." (my bold)

***

"Astronomers first theorized that superbubbles were pervasive in the Milky Way nearly 50 years ago. "Now, we have proof — and what are the chances that we are right smack in the middle of one of these things?" asks Goodman. Statistically, it is very unlikely that the Sun would be centered in a giant bubble if such bubbles were rare in our Milky Way Galaxy, she explains." (my bold)

Comment: note this puts our sun in a very safe quiet spot away from all the dangerous activity in the galaxy. Those supernovas did not disturb evolution and were long enough ago not to harm the arrival of hominins. My bolds ask a question: Is the sun's position lucky or God's work?

4335 views

Our galaxy is huge and appeared quickly after the Big Bang:

https://www.nature.com/articles/s41586-022-04496-5

"The formation of our Milky Way can be split up qualitatively into different phases that resulted in its structurally different stellar populations: the halo and the disk components. Revealing a quantitative overall picture of our Galaxy’s assembly requires a large sample of stars with very precise ages. Here we report an analysis of such a sample using subgiant stars. We find that the stellar age–metallicity distribution p(τ, [Fe/H]) splits into two almost disjoint parts, separated at age τ ≃ 8 Gyr. The younger part reflects a late phase of dynamically quiescent Galactic disk formation with manifest evidence for stellar radial orbit migration4,5,6; the other part reflects the earlier phase, when the stellar halo7 and the old α-process-enhanced (thick) disk, formed. Our results indicate that the formation of the Galaxy’s old (thick) disk started approximately 13 Gyr ago, only 0.8 Gyr after the Big Bang, and 2 Gyr earlier than the final assembly of the inner Galactic halo. Most of these stars formed around 11 Gyr ago, when the Gaia-Sausage-Enceladus satellite merged with our Galaxy10,11. Over the next 5–6 Gyr, the Galaxy experienced continuous chemical element enrichment, ultimately by a factor of 10, while the star-forming gas managed to stay well mixed." (my bold)

Commentary by experts:

"Intagliata: Now Rix and a colleague at the Max-Planck Institute for Astronomy in Germany have indeed gone star by star… determining the ages of nearly a quarter million stars in the Milky Way. That work has allowed them to reconstruct some of the major life events in the galaxy's evolution, over its 13 billion years of existence.

"Rix: What it showed is that indeed the youth and childhood of the Milky Way was turbulent… but actually afterwards we've lived an enormously sheltered life compared to most other galaxies. Gas drizzled in, and the suburbs grew peacefully and sprawled. (my bold)

"Hans-Walter Rix: There were glory days, there were disasters, and all of these things kind of happen in the life of galaxies. And the Milky Way is just the one galaxy where we can look at star by star so you can kind of see individual episodes in actual detail.

"Intagliata: The astronomers say that the galaxy's thick disk began to form about 13 billion years ago, just 800 million years after the Big Bang. Then, around 11 billion years ago, a cataclysmic collision occurred: the Gaia-Enceladus satellite galaxy crashed into the Milky Way. (my bold)

"Rix: And just at the same time, there was a huge burst of star formation, or a large increase of star formation in our own Milky Way. And that suggests—doesn't prove—that the perturbance that this in-falling satellite created, caused a lot of gas that was in our Milky Way to form stars."

My comment: Seems like God was carefully supervising how the Milky Way formed soon after the Big bang. Like our privileged planet, a privileged galaxy.

4192 views

This book says no:

http://www.sci-news.com/physics/timelessness-10738.html?utm_source=feedburner&utm_m...

"Physicists want to produce a theory of ‘quantum gravity’ that replaces general relativity and quantum mechanics, while capturing the extraordinary success of both. Such a theory would explain how gravity’s big picture works at the miniature scale of particles.

"It turns out that producing a theory of quantum gravity is extraordinarily difficult.

"One attempt to overcome the conflict between the two theories is string theory. String theory replaces particles with strings vibrating in as many as 11 dimensions.

"However, string theory faces a further difficulty. String theories provide a range of models that describe a Universe broadly like our own, and they don’t really make any clear predictions that can be tested by experiments to figure out which model is the right one.

"In the 1980s and 1990s, many physicists became dissatisfied with string theory and came up with a range of new mathematical approaches to quantum gravity.

"One of the most prominent of these is loop quantum gravity, which proposes that the fabric of space and time is made of a network of extremely small discrete chunks, or ‘loops.’

"One of the remarkable aspects of loop quantum gravity is that it appears to eliminate time entirely.

"Loop quantum gravity is not alone in abolishing time: a number of other approaches also seem to remove time as a fundamental aspect of reality.

***

"...unless we can come up with a good account of how time emerges, it is not clear we can simply assume time exists.

Time might not exist at any level.

***

"While physics might eliminate time, it seems to leave causation intact: the sense in which one thing can bring about another.

"Perhaps what physics is telling us, then, is that causation and not time is the basic feature of our Universe.

"If that’s right, then agency can still survive. For it is possible to reconstruct a sense of agency entirely in causal terms.

"At least, that’s what Kristie Miller, Jonathan Tallant and I argue in our new book.

"We suggest the discovery that time does not exist may have no direct impact on our lives, even while it propels physics into a new era."

Comment. no surprising at all to me. Time only exists in the minds of observers, in our case, us. Cause and effect must always be present. Every effect has a cause. Therefore, there is a sequence of events at all times. but as humans we codify this into segments we call seconds, minutes, etc., based on the way we have divided up our day/night sequence from Earth's daily rotation. So how about old Einstein? No problem. We have his concept of a fabric of space with sequential cause and effect events and the relative view his observers have from their points of view. Still doesn't get us to one grand unified theory, but another Einstein may be in the wings in the future. Until then quantum mechanics will remain a puzzle. God doesn't explain why this crazy universe is so weird to us, but He doesn't have to, does He? I'll let dhw struggle with that. I don't have to.

4081 views

New study says solar radiation:

https://www.sciencenews.org/article/sun-radiation-solar-system-planet-orbit-astronomy

"In the solar system’s early years, the still-forming giant planets sidestepped, did a do-si-do and then swung one of their partners away from the sun’s gravitational grasp. Things settled, and our planetary system was in its final configuration.

"What triggered that planetary shuffle has been unknown. Now, computer simulations suggest that the hot radiation of the young sun evaporating its planet-forming disk of gas and dust led to the scrambling of the giant planets’ orbits, researchers report in the April 28 Nature.

"As a result, the four largest planets may have been in their final configuration within 10 million years of the solar system’s birth about 4.6 billion years ago. That’s much quicker than the 500 million years that previous work had suggested.

***

"Heaps of evidence, including observations of extrasolar planetary systems forming (SN: 7/2/18), had already indicated that something in our solar system’s early history jumbled the giant planets’ orbits, which scientists call the giant-planet instability.

“'The evidence for the giant-planet instability is really robust,” says Seth Jacobson, a planetary scientist at Michigan State University in East Lansing. “It explains many features of the outer solar system,” he says, like the large number of rocky objects beyond Neptune that make up the Kuiper Belt.

***

"When the sun officially became a star, that is, the moment it began burning hydrogen at its core — roughly 4.6 billion years ago — its ultraviolet emission would have hit the disk’s gas, ionizing it and heating it to tens of thousands of degrees. “This is a very well-documented process,” Jacobson says. As the gas heats, it expands and flows away from the star, beginning with the inner portion of the disk.

“'The disk disperses its gas from inside out,” says Beibei Liu, an astrophysicist at Zhejiang University in Hangzhou, China. He and Jacobson collaborated with astronomer Sean Raymond of Laboratoire d’Astrophysique de Bordeaux in France in the new research.

***

"In their computer simulations, the researchers found that as the sun’s radiation evaporates the disk, a planetary reshuffle nearly always ensues. “We can’t avoid this instability,” Jacobson says."

Comment: still more evidence how God evolves everything from what He starts

3979 views

https://www.newscientist.com/article/2319567-first-picture-of-our-galaxys-supermassive-...

Comment: see the picture. The article dscribes the method

3961 views

How we think it ends:

https://bigthink.com/starts-with-a-bang/how-will-the-universe-end/?utm_source=mailchimp...

"On timescales of a few billion years, we’re pretty confident of what will happen, both locally and cosmically. The Sun will heat up, swell, boil Earth’s oceans, and eventually become a red giant, dying shortly thereafter. The Local Group will remain bound, and the galaxies within it will attract and merge together, triggering new star-formation and depleting our gas. Four billion years from now, the Milky Way and Andromeda will merge together, creating a new galaxy known as Milkdromeda.

"By the time another 10-to-15 billion years have passed, all of the galaxies in the Local Group should experience a gravitational encounter with Milkdromeda, where they’ll be devoured and cannibalized. As the gas within these galaxies forms new generations of stars, it also gets depleted; over time, the star-formation rate will continue to plummet. Without the fuel for forming new stars in great numbers, old stars will die faster than new ones are being born; the number of living stars in our galaxy will start to drop.

"Meanwhile, all the other groups of galaxies will accelerate away from our own. Just as the Local Group becomes more concentrated, so will the other groups and clusters, but only individually.

***

"There are some open questions, however, that could change the story in subtle ways.

"Dark energy may not be a cosmological constant, but could evolve with time, leading to either a Big Crunch or a Big Rip, or something else entirely. We may not be in the true vacuum state of the Universe, and if we experience vacuum decay, so could our fate. Atoms that we presently think are stable could wind up decaying on long enough timescales. And perhaps, although we don’t think it’s the case, it’s plausible that a gravitational interaction in a nearby galaxy group could lead to other members someday joining our Local Group. We can only extrapolate our future based on the limits of what’s known today.

"But that said, we sure do know a lot about what to expect in our far, distant cosmic future! There will come an era where all the distant galaxies beyond our own have disappeared from view. After that, we’ll reach a time where the stars have all gone out, and where all the stellar remnants have faded away. Although the darkness will be punctuated by flashes of light, eventually, the stellar remnants in our galaxy will all be ejected, and the last remaining vestige of matter — our central, supermassive black hole — will decay away. The timescales are tremendous, but still finite; it’s a solemn reminder to enjoy the Universe in all its glory while it’s still here. In this Universe, it truly appears that nothing lasts forever."

Comment: its Ethan Siegel again with his opinion. For those of us who believe in God, there is another issue: Is our universe one and done, were there others before or are others coming? We only live in this one, our only experience, so we will never know.

3827 views

How we think it ends:
https://bigthink.com/starts-with-a-bang/how-will-the-universe-end/?utm_source=mailchimp...

QUOTE: "On timescales of a few billion years, we’re pretty confident of what will happen, both locally and cosmically.”

QUOTE: "There are some open questions, however, that could change the story in subtle ways.”

I am currently applying for a grant to continue my research into what will happen both locally and cosmically 100, 1000, 10,000, 100,000, 1 million, two million, three million etc., 1 billion, two billion, three billion etc. years from now. I’m sure you will appreciate that this is extremely time-consuming work, and I’d be most grateful for your support and that of our readers. $1 million per annum for the next ten years would do me nicely.

3790 views

How we think it ends:
https://bigthink.com/starts-with-a-bang/how-will-the-universe-end/?utm_source=mailchimp...

QUOTE: "On timescales of a few billion years, we’re pretty confident of what will happen, both locally and cosmically.”

QUOTE: "There are some open questions, however, that could change the story in subtle ways.”

dhw: I am currently applying for a grant to continue my research into what will happen both locally and cosmically 100, 1000, 10,000, 100,000, 1 million, two million, three million etc., 1 billion, two billion, three billion etc. years from now. I’m sure you will appreciate that this is extremely time-consuming work, and I’d be most grateful for your support and that of our readers. $1 million per annum for the next ten years would do me nicely.

How did you find out the secret for endless life to do your research into the future? Sell that and you won't need grant money.

3785 views

Known for only 30 years:

https://www.sciencenews.org/article/kuiper-belt-discovery-solar-system-planets-space

"The discovery of 1992 QB1 opened the world’s eyes to the Kuiper Belt, named after Dutch-American astronomer Gerard Kuiper.

***

"Today, researchers know that the Kuiper Belt stretches from a distance of roughly 30 astronomical units from the sun — around the orbit of Neptune — to roughly 55 astronomical units. It resembles a puffed-up disk, Jewitt says. “Superficially, it looks like a fat doughnut.”

"The frozen bodies that populate the Kuiper Belt are the remnants of the swirling maelstrom of gas and dust that birthed the sun and the planets. There’s “a bunch of stuff that’s left over that didn’t quite get built up into planets,” says astronomer Meredith MacGregor of the University of Colorado Boulder. When one of those cosmic leftovers gets kicked into the inner solar system by a gravitational shove from a planet like Neptune and approaches the sun, it turns into an object we recognize as a comet (SN: 9/12/20, p. 14). Comets that circle the sun once only every 200 years or more typically derive from the solar system’s even more distant repository of icy bodies known as the Oort cloud.

^^^

"One long-standing theory, called planetesimal accretion, says that a series of collisions is responsible. Tiny bits of material collide and stick together on repeat to build up larger and larger objects, says JJ Kavelaars, an astronomer at the University of Victoria and the National Research Council of Canada. But there’s a problem, Kavelaars says.

"If Arrokoth formed this way, other bodies in the solar system probably did too. That may mean that parts of the solar system formed much more rapidly than previously believed, says Buie, who discovered Arrokoth in 2014. “Already Arrokoth has rewritten the textbooks on how solar system formation works.”

***

"It’s exciting to think about what we might learn next from the Kuiper Belt, Jewitt says. The discoveries that lay ahead will be possible, in large part, because of advances in technology, he says. “One picture with one of the modern survey cameras is roughly a thousand pictures with our setup back in 1992.”

"But even as we uncover more about this distant realm of the solar system, a bit of awe should always remain, Jewitt says. “It’s the largest piece of the solar system that we’ve yet observed.'”

Comment: There is still a lot to see and understand about our personal solar system

3719 views

The cosmic inflationary period cnfuses the issue:

https://bigthink.com/starts-with-a-bang/big-bang-meaning/?utm_source=mailchimp&utm_...

"The idea that the Universe had a beginning, or a "day without a yesterday" as it was originally known, goes all the way back to Georges Lemaître in 1927. Although it's still a defensible position to state that the Universe likely had a beginning, that stage of our cosmic history has very little to do with the "hot Big Bang" that describes our early Universe. Although many laypersons (and even a minority of professionals) still cling to the idea that the Big Bang means "the very beginning of it all," that definition is decades out of date. Here's how to get caught up.

***

"Originally, the idea was that the Universe itself, not just the matter within it, had emerged from a state of non-being in the finite past. And that idea, as wild as it sounds, was an inevitable but difficult-to-accept consequence of the new theory of gravity put forth by Einstein back in 1915: General Relativity.

***

"If we were to extrapolate backward in time, the Universe would have been in a hotter, denser, more radiation-dominated state. Gamow leveraged this fact to make three great, generic predictions about the young Universe.

"At some point, the Universe’s radiation was hot enough so that every neutral atom would have been ionized by a quantum of radiation, and that this leftover bath of radiation should still persist today at only a few degrees above absolute zero.

"At some even earlier point, it would have been too hot to even form stable atomic nuclei, and so an early stage of nuclear fusion should have occurred, where an initial mix of protons-and-neutrons should have fused together to create an initial set of atomic nuclei: an abundance of elements that predates the formation of atoms.

"And finally, this means that there would be some point in the Universe’s history, after atoms had formed, where gravitation pulled this matter together into clumps, leading to the formation of stars and galaxies for the first time.

***

"The Big Bang, as verified by our observations, accurately and precisely describes the emergence of our Universe, as we see it, from a hot, dense, almost-perfectly uniform early stage.

"But what about the “beginning of time?” What about the original idea of a singularity, and an arbitrarily hot, dense state from which space and time themselves could have first emerged?

"But at the absolute earliest times, this picture breaks down. There was a new idea — proposed and developed in the 1980s — known as cosmological inflation, that made a slew of predictions that contrasted with those that arose from the idea of a singularity at the start of the hot Big Bang. In particular, inflation predicted [a series of facts]:

"On all of these accounts, the inflationary picture has succeeded in ways that the hot Big Bang, without inflation, has not.

***

"Now, there are many reasons to believe that the inflationary state wasn’t one that was eternal to the past, that there might have been a pre-inflationary state that gave rise to inflation, and that, whatever that pre-inflationary state was, perhaps it did have a beginning.

***

"Whether there was a singular, ultimate beginning to all of existence or not, it no longer has anything to do with the hot Big Bang that describes our Universe from the moment that:

"...inflation ended, the hot Big Bang occurred, the Universe became filled with matter and radiation and more, and it began expanding, cooling, and gravitating, eventually leading to the present day.

"There are still a minority of astronomers, astrophysicists and cosmologists who use “the Big Bang” to refer to this theorized beginning and emergence of time-and-space, but not only is that not a foregone conclusion anymore, but it doesn’t have anything to do with the hot Big Bang that gave rise to our Universe. The original definition of the Big Bang has now changed, just as our understanding of the Universe has changed."

Comment: this means the hot inflationary period is all we can see of a beginning for this universe. We can assume a start but it is hidden. The idea of singularity is Newtonian and in light of General Relativity cannot be applied. This is what Guth means by 'past incomplete'.

3653 views

Latest study:

https://www.sciencealert.com/gravity-has-stayed-constant-for-the-entire-age-of-the-univ...

"For over a century, astronomers have known that the Universe has been expanding since the Big Bang. For the first 8 billion years, the expansion rate was relatively consistent since it was held back by the force of gravitation.

"However, thanks to missions like the Hubble Space Telescope, astronomers have since learned that roughly 5 billion years ago, the rate of expansion has been accelerating.

"This led to the widely-accepted theory that a mysterious force is behind the expansion (known as Dark Energy), while some insist that the force of gravity may have changed over time.

***

"But according to a new study by the international Dark Energy Survey (DES) Collaboration, the nature of gravity has remained the same throughout the entire history of the Universe.

***

"So far, the DES Collaboration has measured the shapes of over 100 million galaxies, and the observations all match what General Relativity predicts. The good news is that Einstein's theory still holds, but this also means that the mystery of Dark Energy persists for the time being."

Comment: That means dark matter must exist.

3658 views

From new studies:

https://www.sciencenews.org/article/milky-way-galaxy-nucleus-oldest-stars-protogalaxy

"The Milky Way left its “poor old heart” in and around the constellation Sagittarius, astronomers report. New data from the Gaia spacecraft reveal the full extent of what seems to be the galaxy’s original nucleus — the ancient stellar population that the rest of the Milky Way grew around — which came together more than 12.5 billion years ago.

"The Milky Way’s ancient heart is a round protogalaxy that spans nearly 18,000 light-years and possesses roughly 100 million times the mass of the sun in stars, or about 0.2 percent of the Milky Way’s current stellar mass, Rix and colleagues report in a study posted September 7 at arXiv.org.

***

"Most stars in the Milky Way’s central region abound with metals, because the stars originated in a crowded metropolis that earlier stellar generations had enriched with those metals through supernova explosions. But Rix and his colleagues wanted to find the exceptions to the rule, stars so metal-poor they must have been born well before the rest of the galaxy’s stellar denizens came along — what Rix calls “a needle-in-a-haystack exercise.”

***

"The astronomers then examined how those stars move through space, retaining only the ones that don’t dart off into the vast halo of metal-poor stars engulfing the Milky Way’s disk. The end result: a sample of 18,000 ancient stars that represents the kernel around which the entire galaxy blossomed, the researchers say. By accounting for stars obscured by dust, Rix estimates that the protogalaxy is between 50 million and 200 million times as massive as the sun.

“'That’s the original core,” Rix says, and it harbors the Milky Way’s oldest stars, which he says probably have ages exceeding 12.5 billion years. The protogalaxy formed when several large clumps of stars and gas conglomerated long ago, before the Milky Way’s first disk — the so-called thick disk — arose

"The protogalaxy is compact, which means little has disturbed it since its formation. Smaller galaxies have crashed into the Milky Way, augmenting its mass, but “we didn’t have any later mergers that deeply penetrated into the core and shook it up, because then the core would be larger now,” Rix says.

***

"Today, the Milky Way is a giant galaxy that spins rapidly — each hour our solar system speeds through 900,000 kilometers of space as we race around the galaxy’s center. But the new study shows that the Milky Way got its start as a modest protogalaxy whose stars still shine today, stars that astronomers can now scrutinize for further clues to the galaxy’s birth and early evolution."

Comment: further evidence showing how God evolves His purposes. The story of the Milky Way's evolution is coming clearer.

3603 views

Ethan Siegal's non-answer:

https://bigthink.com/starts-with-a-bang/why-does-nature-obey-laws/?utm_source=mailchimp...

"No matter what physical system we consider, nature always obeys the same fundamental laws. Must it be this way, and if so, why?

"Throughout the entire Universe, everywhere we look, we see an endless variety of structures that have formed at all different stages of cosmic evolution. With a tremendous number of planets, stars, galaxies, clusters of galaxies, and components of the great cosmic web, no two objects that we find are ever identical. And yet, the fundamental laws that they obey — from the quantum to the cosmic — never appear to change. All across the Universe, gravity works the same way, atoms exhibit the same quantum transitions, and the fundamental constants all remain unchanged throughout time and space.

"But why is it that way? Is there anything forbidding it from being different?

***

"Physics, although it’s very good at answering questions of “how” things are, is lousy at taking on questions of purpose, such as “why” things are. Here are the best statements we can make about it.

"In many ways, it’s the most remarkable fact of all about the Universe: that the constituents, the laws, and the constants of nature, on a fundamental level, do not change throughout space and time. Yes, the structures that they bind together to form change; the conditions under which they exist and interplay with one another change; the various phenomena that emerge from their interactions change. The various complex systems that come into existence are chaotic enough that, in all the Universe, no two are ever truly identical.

"But the fundamental constituents (i.e., the particles/quanta), the laws that they obey (i.e., the interactions between them), and the constants that govern their relationships (i.e., the “amount” of any property we examine) are all truly constant.

"If this weren’t the case, reality as we know it would be impossible. The fact that reality is consistent from moment-to-moment and location-to-location is the only thing that enables the Universe to be comprehensible in any meaningful fashion. To illustrate this, let’s look at what would happen if any of these three entities — the constituents, laws, or constants — weren’t universally fixed.

"Imagine that any one of the particles we have and know today, including every particle within the Standard Model, wasn’t a constant. That doesn’t mean “Imagine that one of these particles was unstable,” but rather “Imagine that one of these particles ceased to exist and that either no new particle came to replace it or that one or more novel particles that don’t presently exist came to exist in its stead.”

"What would be the consequence of that?

"The answer, like it or not, is that everything that exists in the Universe, as we know it, would fundamentally cease to exist, and would be replaced with something new."

Comment: He goes on to tell us how it all has to work together in a wonderful exposé of quantum particle physics. But the underlying 'why' is never answered, Fine tuning is never mentioned. The reason why is it has to be this way is to have life appear. It must be exactly like this as a purposeful design for life. It must have been designed!!!

3576 views

Careful mapping shows it:

https://www.nationalgeographic.com/science/article/milky-way-galaxy-has-warped-disk-sta...

"Rather than being flat as a Frisbee, the Milky Way’s star-studded disk is twisted and warped, according to a new three-dimensional map of our home galaxy. If viewed from the side, the spiral arms girdling our galaxy’s bulging core would resemble a record bent into an S shape, or a softly poached egg sliding off a slotted spoon.

“'The warp of the galaxy is so pronounced … if we would be able to see our galaxy from the side, we would clearly see it,” says Dorota Skowron of the University of Warsaw, whose team reports the results today in the journal Science.

***

“'We can see with our own eyes, and inside our own galaxy, that the star formation is not a constant process, but indeed is happening in bursts,” she says.

"Stretching some 120,000 light-years from tip to tip, the Milky Way is what’s known as a spiral galaxy. Four large arms wind around its core, with our sun parked along a minor arm some 26,000 light-years from the center. (my bold)

"The galaxy’s disk of stars and gas is mostly thin and flat toward the middle. But at roughly the sun’s distance from the core, the galaxy begins to bend, flexing upward in one direction and flopping down in the other.

"Near the edges, it gets kind of sloppy: The disk flares, expanding in width from 500 light-years to more than 3,000 light-years, and the warp is even more prominent, with stars living as many as 5,000 light-years above or below the galactic plane.

“'We think the warp may have been caused by interactions with satellite galaxies,” Skowron says, noting that the Milky Way today is surrounded by a swarm of dwarf galaxies. “Other ideas point to interactions with intergalactic gas or dark matter,” she says, referencing the invisible stuff thought to make up 85 percent of the matter in the universe.

"Finding a warped spiral galaxy is not at all unusual; astronomers have observed numerous warped galaxies among the spirals that we can see edge-on, and the stellar conglomerate next door, a giant spiral galaxy called Andromeda, is a similarly twisted sister. But since we sit parked inside the Milky Way, it’s much more challenging to see the large-scale structure of our own galaxy.

"Skowron and her colleagues mapped the Milky Way in three dimensions using 2,431 classical Cepheid variable stars.

"Sometimes shining thousands of times brighter than our sun, Cepheid variables rhythmically brighten and dim with a period that’s tightly linked to their intrinsic brightness. By monitoring those pulses, astronomers can figure out exactly how bright these stars should be, and then use that intrinsic brightness to calculate precise distances—a relationship that Harvard College astronomer Henrietta Swann Leavitt first determined in 1912.

"For years, Skowron and her team watched these big, young stars periodically pulse—even monitoring the ones on the very fringes of our galaxy—using the OGLE instrument, which is mounted on a telescope in Chile, along with several other telescopes. And when Skowron and her colleagues plotted the precise distances to their 2,431 stars, the resulting 3-D galactic map was intriguingly kinked.

“'The structures are well mapped, with accurate distances,” says Annie Robin of the Observatoire de Besancon in France, who has made similar maps using information about how gas is distributed and moves through the galactic disk.

***

"It’s not exactly clear what might have triggered such recent bursts of star formation in a galaxy that now births only a handful of stars each year. Robin notes that slowly moving regions of higher density can compress the gas and dust in interstellar clouds, triggering star formation, while Skowron suggests that a recent interaction with a passing dwarf galaxy could be the culprit.

“'We have to remember that Cepheids [as a group] are relatively young,” Skowron says. “This means that we can use the Cepheids to study only the relatively recent history of our galaxy … so there is still a lot to be discovered about the earlier history of the Milky Way.'”

Comment: for such an old galaxy, the Milky Way is still very active in star-making, and in absorbing minor satellite galaxies which may have given it the twist or bend. Note our safe position on a minor branch of the second spiral arm, away from all the possibly harmful activity in the center. All guided by God, or chance? I'll stick with God.

3579 views

Beyond of our sun's protection cosmic rays are dangerous:

https://www.sciencealert.com/strange-ripples-have-been-detected-at-the-edge-of-the-sola...

"The bubble of space encasing the Solar System might be wrinkled, at least sometimes.

"Data from a spacecraft orbiting Earth has revealed ripple structures in the termination shock and heliopause: shifting regions of space that mark one of the boundaries between the space inside the Solar System, and what's outside – interstellar space.

"The results show that it's possible to get a detailed picture of the boundary of the Solar System and how it changes over time.

"This information will help scientists better understand a region of space known as the heliosphere, which pushes out from the Sun and shields the planets in our Solar System from cosmic radiation.

"There are a variety of ways the Sun affects the space around it. One of those is the solar wind, a constant supersonic flow of ionized plasma. It blows out past the planets and the Kuiper Belt, eventually petering out in the great emptiness between the stars. (my bold)

"The point at which this flow falls below the speed at which sound waves can travel through the diffuse interstallar medium is called the termination shock, and the point at which it is no longer strong enough to push back against the very slight pressure of interstellar space is the heliopause.

"Both Voyager probes have crossed the heliopause and are, effectively, now cruising through interstellar space, providing us the first in situ measurements of this shifting boundary. But there's another tool out in Earth orbit that has been helping scientists map the heliopause since it commenced operations in 2009: NASA's Interstellar Boundary Explorer (IBEX).

"IBEX measures energized neutral atoms, which are created when the Sun's solar wind collides with the interstellar wind at the Solar System boundary. Some of those atoms are catapulted further out into space, while others are flung back at Earth. Once the strength of the solar wind that produced them is taken into account, energized neutral particles that return our way can be used to map the shape of the boundary, a bit like cosmic echolocation.

"Previous maps of the structure of the heliosphere have relied on long-scale measures of the evolution of solar wind pressure and energetic neutral atom emissions, which resulted in a smoothing of the boundary in both space and time. But in 2014, over a period of roughly six months, the dynamic pressure of the solar wind increased by roughly 50 percent."

Comment: the rest of the article describes heliosphere boundary measurements. What I find interesting is how the sun's solar wind stops cosmic rays and protects us.

3532 views

Joining of two black holes provide this proof:

https://www.livescience.com/black-hole-merger-precession-einstein?utm_campaign=368B3745...

"Researchers studying the aftermath of a gargantuan black hole collision may have confirmed a gravitational phenomenon predicted by Albert Einstein a century ago.

"According to new research published today (Oct. 12) in the journal Nature(opens in new tab), the phenomenon — which is known as precession and is similar to the wobbling motion sometimes seen in a spinning top — occurred when two ancient black holes crashed together and merged into one. As the two massive objects swirled closer together, they released enormous ripples through the fabric of space-time known as gravitational waves, which surged outward across the cosmos, carrying energy and angular momentum away from the merging black holes.

***

"The spinning black hole was twisting and turning 10 billion times faster than any previously observed black hole, which distorted space and time so much that it caused both black holes to wobble — or precess — in their orbits.

"Researchers have observed precession in everything from spindle tops to dying star systems, but never in objects as enormous as binary black hole systems, in which the two cosmic vacuum cleaners orbit around a common center. However, Einstein's theory of general relativity predicted more than 100 years ago that precession should occur in objects as large as binary black holes. Now, the study authors say, this rare phenomenon has been observed in nature for the first time.

***

"This new research in Nature suggests that the two black holes had a chaotic relationship before their violent merger. As the two gargantuan objects tugged at each other in an ever-closer orbit, they began to wobble like tipsy tops, precessing several times every second. According to the study authors, this precessing effect is estimated to be 10 billion times faster than any other ever measured.

"These findings vindicate Einstein, who predicted that such effects were possible in some of the universe's largets objects. But the results also raise the question as to whether wibbly wobbly black hole mergers like this one are as rare as once thought."

Comment: Einstein is always right.

3517 views

The danger of incoming asteroids was noted before; problem solved:

https://www.scientificamerican.com/article/darts-smashing-success-shows-humanity-can-di...

"Humans have for the first time proven that they can change the path of a massive rock hurtling through space. NASA has announced that the spacecraft it slammed into an asteroid on 26 September succeeded in altering the space rock’s orbit around another asteroid — with better-than-expected results.

"Agency officials had estimated that the Double Asteroid Redirection Test (DART) spacecraft would ‘nudge’ the asteroid Dimorphos closer to its partner, Didymos, and cut its orbit time around that rock by 10–15 minutes. At an 11 October press conference, researchers confirmed that DART in fact cut the orbit time by around 32 minutes.

"Neither asteroid was a threat to Earth, but the agency tested the manoeuvre on them to prove that humanity could, in principle, deflect a worrisome space rock heading for the planet.

“'This is a watershed moment for planetary defence, and a watershed moment for humanity,” said NASA administrator Bill Nelson.

***

"Although the orbit reduction is larger than expected, it still falls within the range of possibilities that scientists modelled. Researchers think the manouevre succeeded to the extent that it did because Dimorphos is more a loose collection of rocks than a solid chunk that would be harder to deflect. Another reason for the dramatic orbit change is that when DART hit, a lot of debris shot out from the asteroid into tails, each one thousands of kilometres long, and their recoil probably accentuated DART’s impact, researchers said at the press conference.

"For now, the results indicate that the US$330-million DART mission was a success. But defending Earth from future impacts requires a few things, researchers say: knowing the locations and properties of any dangerous space rocks, and having enough time to act. DART launched in November last year and took about 10 months to hit its target.

"If a threatening asteroid really were headed towards Earth, said Nancy Chabot, a planetary scientist and the DART coordination lead at Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, a mission would need to launch years in advance to deflect it safely. “Warning is really key here,” she said, adding that even space rocks larger than the 160-metre-wide Dimorphos might be dealt with given enough planning and time."

Comment: The methodology is proven but lots more preparation needs be done

3555 views

Final proof of Big Bang theoryL

https://bigthink.com/starts-with-a-bang/big-bangs-final-prediction/?utm_source=mailchim...

"As time went forward, the Universe would cool, expand, and gravitate all together. First atomic nuclei would form from protons and neutrons, then neutral atoms would form, and then gravitation would lead to stars, galaxies, and the grand structures of the cosmic web. These leftover relics — the light elements formed in the Big Bang, the relic photons from the primordial plasma, and the large-scale structure of the Universe — would, along with the cosmic expansion of the Universe, form the four cornerstones of the Big Bang.

"But from an even earlier epoch, a fifth cornerstone should exist as well. There would be an early signal left over from when the Universe was just one second old: a bath of neutrinos and antineutrinos. Known as the cosmic neutrino background (CNB), it was theorized generations ago but was dismissed as undetectable. But no longer. Two very clever teams of scientists found a way to detect it. The data is in, and the results are incontrovertible: the cosmic neutrino background is real, and agrees with the Big Bang. Here’s how the Big Bang’s last great prediction was confirmed.

"Neutrinos are some of the most surprising and elusive particles in the Universe. They were predicted in 1930 to explain radioactive decays, as otherwise, energy and momentum would not be conserved.

***
"...neutrinos are real, and they’re fundamental particles, just like electrons or quarks are. They come in three generations: electron neutrino, muon neutrino, and tau neutrino, just like all of the other Standard Model fermions. They interact only through the weak and gravitational forces, so they neither absorb or emit light. But at high energies, like those achieved in the earliest stages of the hot Big Bang, the weak interactions were much stronger. Under those conditions, the early Universe spontaneously created enormous amounts of both neutrinos and their antimatter counterparts, antineutrinos.

***

"The neutrinos and antineutrinos, which stop interacting with the primordial plasma when the Universe is just one second old, should remain until the present day.

***

"This cosmic neutrino background (CNB) has been theorized to exist for practically as long as the Big Bang has been around, but has never been directly detected. Because neutrinos have such a tiny cross-section with other particles, we generally need them to be at very high energies in order to see them...No proposed experiments are theoretically capable of seeing them unless some novel, exotic physics is at play.

***

"If neutrinos weren’t present, the radiation content would be described by the photons alone; if neutrinos were present, however, the radiation content would need to be described by both photons and neutrinos combined. In other words, these neutrinos, if the cosmic neutrino background (CNB) is real, will create imprints in the CMB, and those imprints will persist all the way to the present day, where they should show up in the Universe’s large-scale structure as well.

"The effects on the CMB will be subtle, but measurable. The pattern of peaks and valleys will be stretched out and moved to larger scales — albeit extremely slightly — by the presence of neutrinos. In terms of what can be observed, the peaks and valleys will have their phases shifted by a measurable amount that depends on both the number of neutrinos that exist and the temperature (or energy) of those neutrinos at early times. This phase shift, if detectable, would provide not only strong evidence of the existence of the cosmic neutrino background, but would allow us to measure its temperature, putting the Big Bang to the test in a brand new way.

"Meanwhile, the downstream consequences of the cosmic neutrino background’s existence will show up by imprinting their effects on the present-day large-scale structure of the Universe. This imprint will also be subtle, but with enough precision in how we measure the various correlations between galaxies across cosmic distances, it should be theoretically measurable as well.

***

"The cosmic neutrino background may not be directly detectable today, but its indirect effects on two observables — the CMB and the large-scale structure of the Universe — should remain detectable, even 13.8 billion years after the hot Big Bang.

***

"In 2015, using the novel data from the ESA’s Planck satellite, a quartet of scientists published the first detection of the imprint of the cosmic neutrino background on the relic light from the Big Bang: the CMB. The data were consistent with there being three and only three species of light neutrino, consistent with the electron, muon, and tau species we’ve directly detected through particle physics experiments.

***

"Leveraging this large-scale structure data, we’ve now measured the phase shifts in the galaxy correlation data well enough to robustly announce that the presence of cosmic neutrinos have been detected."

***

Comment: the measurements fit exactly with the theory of the Standard Model. That makes the Big Bang really real.

3568 views

Pantheon+ is the new approach:

https://phys.org/news/2022-10-precise-accounting-dark-energy.html

"Pantheon+ convincingly finds that the cosmos is composed of about two-thirds dark energy and one-third matter—mostly in the form of dark matter—and is expanding at an accelerating pace over the last several billion years. However, Pantheon+ also cements a major disagreement over the pace of that expansion that has yet to be solved.

***

"'With these Pantheon+ results, we are able to put the most precise constraints on the dynamics and history of the universe to date," says Dillon Brout, an Einstein Fellow at the Center for Astrophysics | Harvard & Smithsonian. "We've combed over the data and can now say with more confidence than ever before how the universe has evolved over the eons and that the current best theories for dark energy and dark matter hold strong."

***

"Pantheon+ is based on the largest dataset of its kind, comprising more than 1,500 stellar explosions called Type Ia supernovae. These bright blasts occur when white dwarf stars—remnants of stars like our Sun—accumulate too much mass and undergo a runaway thermonuclear reaction.

***

"Because Type Ia supernovae outshine entire galaxies, the stellar detonations can be glimpsed at distances exceeding 10 billion light years, or back through about three-quarters of the universe's total age. Given that the supernovae blaze with nearly uniform intrinsic brightnesses, scientists can use the explosions' apparent brightness, which diminishes with distance, along with redshift measurements as markers of time and space.

***

"Taking the data as a whole, the new analysis holds that 66.2 percent of the universe manifests as dark energy, with the remaining 33.8 percent being a combination of dark matter and matter.

"To arrive at even more comprehensive understanding of the constituent components of the universe at different epochs, Brout and colleagues combined Pantheon+ with other strongly evidenced, independent and complementary measures of the large-scale structure of the universe and with measurements from the earliest light in the universe, the cosmic microwave background.

"Another key Pantheon+ result relates to one of the paramount goals of modern cosmology: nailing down the current expansion rate of the universe, known as the Hubble constant. Pooling the Pantheon+ sample with data from the SH0ES (Supernova H0 for the Equation of State) collaboration, led by Riess, results in the most stringent local measurement of the current expansion rate of the universe.

"Pantheon+ and SH0ES together find a Hubble constant of 73.4 kilometers per second per megaparsec with only 1.3% uncertainty. Stated another way, for every megaparsec, or 3.26 million light years, the analysis estimates that in the nearby universe, space itself is expanding at more than 160,000 miles per hour.

"However, observations from an entirely different epoch of the universe's history predict a different story. Measurements of the universe's earliest light, the cosmic microwave background, when combined with the current Standard Model of Cosmology, consistently peg the Hubble constant at a rate that is significantly less than observations taken via Type Ia supernovae and other astrophysical markers. This sizable discrepancy between the two methodologies has been termed the Hubble tension.

"The new Pantheon+ and SH0ES datasets heighten this Hubble tension. In fact, the tension has now passed the important 5-sigma threshold (about one-in-a-million odds of arising due to random chance) that physicists use to distinguish between possible statistical flukes and something that must accordingly be understood. Reaching this new statistical level highlights the challenge for both theorists and astrophysicists to try and explain the Hubble constant discrepancy.

***

"Overall, Pantheon+ offers scientists a comprehensive lookback through much of cosmic history. The earliest, most distant supernovae in the dataset gleam forth from 10.7 billion light years away, meaning from when the universe was roughly a quarter of its current age. In that earlier era, dark matter and its associated gravity held the universe's expansion rate in check.

"Such state of affairs changed dramatically over the next several billion years as the influence of dark energy overwhelmed that of dark matter. Dark energy has since flung the contents of the cosmos ever-farther apart and at an ever-increasing rate.

"With this combined Pantheon+ dataset, we get a precise view of the universe from the time when it was dominated by dark matter to when the universe became dominated by dark energy," says Brout. "This dataset is a unique opportunity to see dark energy turn on and drive the evolution of the cosmos on the grandest scales up through present time.'"

Comment: we are getting a more complete story of the evolution of the universe

3480 views

Now determined:

https://bigthink.com/hard-science/speed-of-gravity/?utm_source=mailchimp&utm_medium...

"Of all of the fundamental forces known to humanity, gravity is both the most familiar and the one that holds the Universe together, connecting distant galaxies in a vast and interconnected cosmic web. With that in mind, a fascinating question to ponder is whether gravity has a speed. It turns out that it does, and scientists have precisely measured it.

***

"Different answers have been proposed throughout scientific history. Sir Isaac Newton, who invented the first sophisticated theory of gravity, believed the speed of gravity was infinite. He would have predicted that the Earth’s path through space would change before Earth-bound humans noticed that the Sun was gone.

"On the other hand, Albert Einstein believed that gravity traveled at the speed of light. He would have predicted that humans would simultaneously notice the disappearance of the Sun and the change of Earth’s path through the cosmos. He built this assumption into his theory of general relativity, which is currently the best accepted theory of gravity, and it very precisely predicts the path of the planets around the Sun. His theory makes more accurate predictions than Newton’s. So, can we conclude that Einstein was right?

***

"Although gravitational waves are emitted when two black holes collide, that’s not the only possible cause. Gravitational waves are also emitted when two neutron stars slam together. Neutron stars are also burned-out stars — similar to black holes, but slightly lighter. Furthermore, when neutron stars collide, not only do they emit gravitational radiation, they also emit a powerful burst of light that can be seen across the Universe. To determine the speed of gravity, scientists needed to see the merging of two neutron stars.

"In 2017, astronomers got their chance. They detected a gravitational wave and a little over two seconds later, orbital observatories detected gamma radiation, which is a form of light, from the same location in space originating in a galaxy located 130 million light years away. Finally, astronomers found what they needed to determine the speed of gravity.

"The merging of two neutron stars emits both light and gravitational waves at the same time, so if gravity and light have the same speed, they should be detected on Earth at the same time. Given the distance of the galaxy that housed these two neutron stars, we know that the two types of waves had traveled for about 130 million years and arrived within two seconds of one another.

"So, that’s the answer. Gravity and light travel at the same speed, determined by a precise measurement. It validates Einstein once again, and it hints at something profound about the nature of space. Scientists hope one day to fully understand why these two very different phenomena have identical speeds."

Comment: an important finding.

3487 views

They ae dangerous to life:

https://www.universetoday.com/158316/how-dangerous-are-nearby-supernovae-to-life-on-earth/

Life and supernovae don’t mix.

From a distance, supernovae explosions are fascinating. A star more massive than our Sun runs out of hydrogen and becomes unstable. Eventually, it explodes and releases so much energy it can outshine its host galaxy for months.

But space is vast and largely empty, and supernovae are relatively rare. And most planets don’t support life, so most supernovae probably explode without affecting living things.

Earth is no stranger to supernovae. One hasn’t been close enough to sterilize Earth, but there’s evidence showing supernovae have affected life on Earth.

A 2018 paper presented evidence of a supernova exploding near Earth about 2.6 million years ago. It was about 160 light-years away. The authors of that paper tied the supernova to the Pliocene marine megafauna extinction. In that event, up to a third of Earth’s large marine species were wiped out, but only in shallow coastal waters.

Another paper showed up to 20 supernovae in the last 11 million years in the Scorpius-Centaurus OB association. Some of these were as close as 130 light-years to Earth. The paper’s authors say that about 2 million years ago, one of the supernovae exploded close enough to our planet to damage the ozone layer.

***

In a scenario where an SN exploded close to Earth, it can take months or years following the initial explosion for the x-rays to arrive. Interactions with the circumstellar debris cause a delay. The x-rays can deplete Earth’s ozone layer, allowing harmful UV radiation from the Sun to reach the planet’s surface.

After the x-rays arrive, the cosmic rays arrive, similar to other SN. This is a double whammy for Earth’s ozone layer.

***

Our Solar System is inside what’s known as the Local Bubble. It’s a cavity carved out of the ISM [interstellar medium] in the Milky Way’s Orion Arm. Multiple supernovae explosions created the bubble in the last 10 to 20 million years. Did those SN affect Earth? (my bold)

Advances in x-ray astronomy will shed more light on the consequences for terrestrial planets, and the authors think there’s lots more to uncover. But their observations show that “… the interacting X-ray phase of an SN’s evolution can entail significant consequences for terrestrial planets. We limit any further speculation until further developments in X-ray astronomy are made; however, the evidence presented here certainly points to this process as capable of imposing lethal consequences for life at formidable distances.”

Scientists know that supernovae have had some effect on Earth. The presence of the radioactive isotope 60Fe has a half-life of 2.6 million years, yet researchers found undecayed 60Fe in ocean samples dating from 2 to 3 Myr ago. It should’ve decayed into nickel long ago. Supernovae can create 60Fe through nucleosynthesis when they explode.

But other things can create 60Fe. Asymptomatic giant branch stars can make it, too, so by itself, it’s not a smoking gun for a nearby supernova.

Researchers also found 53Mn in the same samples of ferromanganese crust that hold the 60Fe. It’s also a radioactive isotope that should’ve decayed by now. Unlike 60Fe, only supernovae can create 53Mn. Its presence is definite proof of nearby supernovae in the recent geological past.

It’s not the presence of these radioactive isotopes that poses a threat to life. It’s the radiation that must’ve struck Earth, and if the supernova that created the isotopes was close enough to spread them to Earth, then the radiation must’ve struck Earth, too.

***

SN outbursts have almost certainly struck our planet. The exact consequences are difficult for scientists to untangle. But if the radiation weakened the ozone layer, allowing more UV radiation to reach the Earth’s surface, it would’ve caused mutations. It’s called UV mutagenesis, which may have driven molecular evolution and been critical in the origin of sex. In fact, mutation is evolution’s primary driver.

The fact that supernovae can lead to mutations is the backdrop for the authors’ concluding remarks.

“We thus conclude with the comment that further research into SN X-ray emission has value not just for stellar astrophysics but also for astrobiology, paleontology, and the Earth and planetary sciences as a whole.”

***

The researchers urge more long-term study of supernovae for months and years after an outburst and plea for more advancements in x-ray observation to aid the study. “These observations and innovations will shed light on the physical nature of SN X-ray emission and will clarify the danger that these events pose for life in our galaxy and other star-forming regions,” they write.

Comment: note my bold. We are in a very safe spot in the 'bubble'.

3544 views

Our different ways of studying the universe reach conflicting results:

https://bigthink.com/starts-with-a-bang/new-anomaly-universe/?utm_source=mailchimp&...

"Early relics and late-time objects give incompatible results for the expanding Universe. This independent anomaly intensifies the problem.

"The most puzzling, unexplained anomaly in all of cosmology is the Hubble tension: the difference in the measured expansion rate depending on which method is used. However, a second, less-publicized anomaly is also extremely puzzling: a difference in our observed motion through the Universe and how different things appear in various directionsConsider the cosmic microwave background (CMB): leftover radiation from the Big Bang.. We have many different methods of estimating how the Universe differs in different directions, and they're not all consistent with one another. That's a real, unsolved, but important problem!

"The largest anomaly is the Hubble tension. Two expansion rate measurement methods yield incompatible values. The early relic method, via cosmic imperfections, yields 67 km/s/Mpc. The distance ladder method, from individually measured objects, yields 73 km/s/Mpc.

"But another cosmic imperfection anomaly is similarly puzzling. Although mostly uniform, one direction is ~3.3 millikelvin hotter while the opposite is similarly cooler. This “CMB dipole” reflects our Sun’s relative motion to the CMB: of ~370 km/s. (look at the article to see the illustration) Our Local Group moves much faster: ~620 km/s. This should be due to cosmic, gravitational imperfections tugging on us. Nearby galaxy motions consistently support this picture. However, more distant motion tracers conflict with it. Plasmas within clusters indicate smaller overall motions: below ~260 km/s. The brightest cluster galaxies, however, reveal larger motions: ~689 km/s. Cluster scaling relations reveal giant, wrong-directional motions of ~900 km/s. And anisotropies in galaxy counts reveal more than double the expected effect. Radio galaxy counts are even worse: four times the expected amplitude. Quasar counts from WISE [NASA’s Wide-field Infrared Survey Explorer] possess the same problem. Larger-scale, upcoming surveys could robustly confirm this second “Hubble tension.'”

Comment: That we measure the Hubble rate of expansion in two ways, and they don't agree tells us we still haven't defined the universe's properties in a reliable way. Download the article to see more explanations and illustrations

3446 views

A review article:

https://www.sciencealert.com/we-have-precise-math-that-can-describe-how-black-holes-ref...

"Astronomers developed a set of equations that can precisely describe the reflections of the Universe that appear in the warped light around a black hole.

"The proximity of each reflection is dependent on the angle of observation with respect to the black hole, and the rate of the black hole's spin, according to a mathematical solution worked out by physics student Albert Sneppen of the Niels Bohr Institute in Denmark in July 2021.

"This was really cool, absolutely, but it wasn't just really cool. It also potentially gave us a new tool for probing the gravitational environment around these extreme objects.

"'There is something fantastically beautiful in now understanding why the images repeat themselves in such an elegant way," Sneppen said in a 2021 statement. "On top of that, it provides new opportunities to test our understanding of gravity and black holes."

"If there's one thing that black holes are famous for, it's their extreme gravity. Specifically that beyond a certain radius, the fastest achievable velocity in the Universe, that of light in a vacuum, is insufficient to achieve escape velocity.

"That point of no return is the event horizon – defined by what's called the Schwarszchild radius – and it's the reason why we say that not even light can escape from a black hole's gravity.

"Just outside the black hole's event horizon, however, the environment is also seriously wack. The gravitational field is so powerful that the curvature of space-time is almost circular.

***

"At the very inner edge of this space, just outside the event horizon, we can see what is called a photon ring, where photons travel in orbit around the black hole multiple times before either falling towards the black hole or escaping into space.

"This means that the light from distant objects behind the black hole can be magnified, distorted, and 'reflected' several times. We refer to this as a gravitational lens; the effect can also be seen in other contexts and is a useful tool for studying the Universe.

"So we've known about the effect for some time, and scientists had figured out that the closer you look toward the black hole, the more reflections you see of distant objects.

"To get from one image to the next image, you needed to look about 500 times closer to the black hole's optical edge, or the exponential function of two pi (e2π), but why this was the case was difficult to mathematically describe.

"Sneppen's approach was to reformulate the light trajectory and quantify its linear stability, using second order differential equations. He found not only did his solution mathematically describe why the images repeat at distances of e2π, but that it could work for a rotating black hole – and that repeat distance is dependent on spin.

"'It turns out that when it rotates really fast, you no longer have to get closer to the black hole by a factor of 500, but significantly less," Sneppen said. "In fact, each image is now only 50, or five, or even down to just two times closer to the edge of the black hole."

***

"Theoretically, however, there should be infinite rings of light around a black hole. Since we have imaged the shadow of a supermassive black hole once, it's hopefully only a matter of time before we're able to obtain better images, and there are already plans for imaging a photon ring.

"One day, the infinite images close to a black hole could be a tool for studying not just the physics of black hole space-time, but the objects behind them – repeated in infinite reflections in orbital perpetuity."

Comment: from proposing they might exist, to proving they do and then using their properties to study the universe is an amazing history of human ingenuity. From Paul Davies' view our appearance is a highly significant event to dhw's constant diminishing of it shows a range of how our humanity is philosophized.

3540 views

Just found:

https://www.sciencealert.com/potentially-hazardous-monster-asteroid-is-the-largest-seen...

"Astronomers peering into the twilight sky have found three previously unknown near-Earth asteroids. One of which is the largest potentially hazardous asteroid discovered in eight years.

"It measures roughly 1.5 kilometers (nearly 1 mile) across, and is on an orbit that may, in the future, bring it close enough to Earth to pose a problem.

"The other two asteroids have paths that are entirely, and safely, closer to the Sun than Earth's orbit. That doesn't make their discovery any less exciting, adding to a census of hard-to-find objects that will allow us to better characterize the population of near-Earth objects.

***

"To have a chance of spotting an inner Solar System asteroid, astronomers need to wait until the twilight hours at dawn and dusk when the Sun's glare mostly lies below Earth's horizon, providing just enough light to illuminate inner asteroids that might be sweeping through space.

"A research team led by astronomer Scott S. Sheppard of the Carnegie Institution for Science conducted just such a search of large patches of the sky nearer to the Sun than Earth and Venus, leading to some fascinating discoveries.

"One was 2021 PH27, an asteroid with the shortest orbit of any asteroid found yet, at just 113 days. Then there's 2021 LJ4, which also circles the Sun entirely within Earth's orbit. Both are known as Atira asteroids.

"'So far we have found two large near-Earth asteroids that are about 1 kilometer across, a size that we call planet killers," Sheppard says.

"There are likely only a few near-Earth asteroids with similar sizes left to find, and these large undiscovered asteroids likely have orbits that keep them interior to the orbits of Earth and Venus most of the time. Only about 25 asteroids with orbits completely within Earth's orbit have been discovered to date because of the difficulty of observing near the glare of the Sun."

"The third asteroid, 2022 AP7, is known as an Apollo asteroid. These are asteroids that have elliptical paths that take them from a space nearer to the Sun to beyond Earth's orbit. By crossing our orbit, Apollo asteroids like 2022 AP7 could venture close enough to our planet to risk a collision, earning them a classification of "potentially hazardous".

"There are over 2,000 potentially hazardous asteroids (the largest of which is around 7 kilometers across) that we thankfully know about. If we know about them, we can model their orbits, and calculate if and when they are likely to come within hazardous range of Earth. With enough notice, we might be able to do something about it, like slam a spacecraft into their surface to divert their course.

***

"'Our DECam survey is one of the largest and most sensitive searches ever performed for objects within Earth's orbit and near to Venus's orbit," Sheppard says. "This is a unique chance to understand what types of objects are lurking in the inner Solar System."

"Interestingly, in spite of being more sensitive to smaller objects, the survey has uncovered a greater number of larger asteroids – those at least a kilometer across. This could mean smaller asteroids are less stable in the inner Solar System, or more susceptible to breaking apart in the intense thermal and gravitational environment closer to the Sun.

"It might simply be that smaller asteroids are harder to detect, though. This makes an excellent case for more sensitive surveys in the future."

Comment: these dangers have been discussed before. Recently we noted a well-aimed rocket nudged a small one off course.

3394 views

A black hole can have more than one mass due to quantum effects:

https://phys.org/news/2022-10-uncovering-massive-quantum-mysteries-black.html

"Bizarre quantum properties of black holes—including their mind-bending ability to have different masses simultaneously—have been confirmed by University of Queensland physicists.

***

"'But, until now, we haven't deeply investigated whether black holes display some of the weird and wonderful behaviors of quantum physics.

"'One such behavior is superposition, where particles on a quantum scale can exist in multiple states at the same time.

"'This is most commonly illustrated by Schrödinger's cat, which can be both dead and alive simultaneously.

"'But, for black holes, we wanted to see whether they could have wildly different masses at the same time, and it turns out they do.

***

"...the team developed a mathematical framework allowing us to "place" a particle outside a theoretical mass-superposed black hole.

"Mass was looked at specifically, as it is a defining feature of a black hole, and as it is plausible that quantum black holes would naturally have mass superposition.

"Research co-supervisor, Dr. Magdalena Zych, said that the research in fact reinforces conjectures raised by pioneers of quantum physics.

"'Our work shows that the very early theories of Jacob Bekenstein—an American and Israeli theoretical physicist who made fundamental contributions to the foundation of black hole thermodynamics—were on the money," she said.

"'He postulated that black holes can only have masses that are of certain values, that is, they must fall within certain bands or ratios—this is how energy levels of an atom works, for example.

"'Our modeling showed that these superposed masses were, in fact, in certain determined bands or ratios—as predicted by Bekenstein.

"'We didn't assume any such pattern going in, so the fact we found this evidence was quite surprising.

"'The universe is revealing to us that it's always more strange, mysterious and fascinating than most of us could have ever imagined.'"

Comment: that last statement is certainly true. I still wonder why God did it that way?

3481 views

Not by light:

https://www.sciencemagazinedigital.org/sciencemagazine/library/item/04_november_2022/40...

"After relying on nothing but light to study the cosmos for centuries, the development of multimessenger astronomy in the past decade has revolutionized the field. The successful detections of the additional messengers—i.e., information carriers other than light—are only possible because of state-of-the-art, large-scale instruments, such as the detectors at the IceCube Neutrino Observatory, which are located a kilometer deep inside the Antarctic ice. High-energy cosmic neutrinos have given rise to both surprises and mysteries since their detections were reported in 2013.

***

"In space, high-energy neutrinos are mainly produced by cosmic rays—i.e., protons and atomic nuclei that are traveling at nearly the speed of light—colliding with matter or radiation, which creates subsequent particles that later decay into neutrinos and gamma rays. Such collisions occur inside astrophysical objects, such as galaxies and black hole jets, or in intergalactic space between those objects and Earth. Revealing the origin of cosmic neutrinos and the relationship among neutrinos, gamma rays, and cosmic rays is crucial to deciphering the fundamental processes that occur throughout the Universe (1). Neutrinos are also special because they can travel through dense environments that are impassable for photons, which allow astronomers to “see” behind gas, dust, and radiation obstructions.

"Active galactic nuclei (AGNs), which exist at the centers of some galaxies, are energized by either the accretion of gas onto a supermassive black hole and/or the spin of the black hole at the center of the galaxies. They are among the most promising candidate sources of not only the highest-energy cosmic rays but also high-energy cosmic neutrinos observable from Earth.

***

"...searches relying on the population of gamma ray–detected blazars have suggested that this class of AGN alone would not explain the amount of all cosmic neutrinos (9) coming from every direction in the sky (not every detected neutrino has a well-defined source of origin). This has prompted ideas for other classes of neutrino sources besides blazars.

***

"The source of the detected neutrinos—NGC 1068—is among the brightest and closest AGNs from Earth. It is located in the constellation Cetus, at a distance of ∼46 million light-years away. Optical images of NGC 1068 show a rather normal barred spiral galaxy, with a bright starburst inner disk and star-forming regions in the outer arms. The galactic nucleus is classified as a type of AGN that is characterized by emission lines in the optical spectrum. It is also considered a radio-quiet AGN that does not have powerful jets, as seen in blazars. Its nucleus is luminous not only in the optical and infrared bands, but also in ultraviolet and x-ray bands, which are thought to largely come from the accretion disk and hot corona near the supermassive black hole at the galactic center. The black hole is estimated to be ∼15 million times as massive as the Sun and is considered to be one of the most obscured supermassive black holes known, being blanketed by thick gas and dust. X-ray observations from the Nuclear Spectroscopic Telescope Array indicate that the x-rays are largely intervened by the gas, and radio data from the Atacama Large Millimeter/submillimeter Array have suggested a compact gaseous structure with a radius of ∼10 light-years around the black hole (12). Once the x-ray emission is corrected by accounting for absorption by the gas, NGC 1068 has the brightest x-ray emission among radio-quiet AGNs in the sky region targeted by the IceCube Neutrino Observatory, which helps explain the neutrino excess."

Comment: it is obvious photon detection alone tells a tiny part of the story of how the universe works. We still have no answer for dhw who wonders why the universe is so big and so complex, if all God wanted was to create some humans on Earth. My simple answer is God knows what He is doing.

3399 views

Based on a recent exercise and not including the recent asteroid deflection:

https://www.scientificamerican.com/article/nasa-asteroid-threat-practice-drill-shows-we...

"The exercise was a simulation where academics, scientists and government officials gathered to practice how the United States would respond to a real planet-threatening asteroid. Held February 23–24, participants were both virtual and in-person, hailing from Washington D.C., the Johns Hopkins Applied Physics Lab (APL) campus in Laurel, Md., Raleigh and Winston-Salem, N.C. The exercise included more than 200 participants from 16 different federal, state and local organizations. On August 5, the final report came out, and the message was stark: humanity is not yet ready to meet this threat.

***

"All in all, the exercise demonstrated that the United States doesn’t have the capability to intercept small, fast-moving asteroids, and our ability to see them is limited. Even if we could intercept space rocks, we may not be able to deflect one away from Earth, and using a nuclear weapon to destroy one is risky and filled with international legal issues. The trial also showed that misinformation—lies and false rumors spreading among the public—could drastically hamper the official effort. “Misinformation is not going away,” says Angela Stickle, a senior research scientist at APL who helped design and facilitate the exercise. “We put it into the simulation because we wanted feedback on how to counteract it and take action if it was malicious.”

***

"Blasting an asteroid in space may result in a cluster of smaller but still-dangerous, fast-moving rocks. And an upper-atmosphere detonation of a nuclear weapon has unknown but most likely dangerous effects. The explosion may not fully disintegrate the rock, forcing portions of it down somewhere else. Radiation could persist in the upper atmosphere at levels making traveling through it on your way to space prohibitive.

"With no way to stop the asteroid from hitting Earth, the exercise was all about mitigation—what must be done leading up to the impact and in the immediate aftermath. Organizations at all levels needed to be in contact, emergency plans had to be developed and enacted, and the public informed."

Comment: even if the current abilities are nowhere near perfect, at least we recognize the deficiencies. The 10/14 entry about deflecting an asteroid was just a start.

3411 views

Further studies:

https://bigthink.com/starts-with-a-bang/earth-threatening-asteroid/?utm_source=mailchim...

"A ~kilometer-sized or greater object could wipe out every human on Earth.

***

"Three new major discoveries reveal how fundamentally unprepared we truly are

***

"These new near-Earth asteroids were all found in an uncommon place: between the orbits of Earth and Venus.

"Another, at 1.5 kilometers across, is the largest Earth-hazardous asteroid discovered in eight years.

"If a collision occurs, an extinction-level event is anticipated.

"Hazardous object surveys primarily focus on the asteroid belt: where most such objects are located.

"However, those don’t include the four major Earth-threatening classes:

Amors
Earth-approaching NEAs with orbits
exterior to Earth's but interior to Mars'
(named after asteroid (1221) Amor)

a > 1.0 AU
1.017 AU < q < 1.3 AU
a > 1.0 AU

Apollos
Earth-crossing NEAs with semi-major
axes larger than Earth's
(named after asteroid (1862) Apollo)

9 < 1.017 AU
a < 1.0 AU
2 > 0.983 AU

Atens
Earth-crossing NEAs with semi-major
axes smaller than Earth's
(named after asteroid (2062) Aten)

Atiras
NEAs whose orbits are contained
entirely within the orbit of the Earth
(named after asteroid (163693) Atira)

a < 1.0 AU
Q < 0.983 AU
= perihelion distance, Q = aphelion distance, a = semi-major axis

***

"Most such hazards remain unidentified, necessitating space-based missions, like NEO Surveyor."

Comment: See the article for diagrams and further explanations. I downloaded one text just above. If our God is a deist, we are on our own. If He is a theist He will help.

3435 views

The hunt goes on:

https://www.quantamagazine.org/alien-life-a-dream-of-discovery-finds-new-hope-20221103/

"Kaltenegger has since become perhaps the world’s leading computer modeler of potentially habitable worlds. In 2019, when another exoplanet-hunting NASA spacecraft called TESS found its own first rocky, temperate worlds, she was called on again to play the role of cosmic home inspector. Most recently, the Belgium-based SPECULOOS survey reached out for her help understanding a newfound Earth-size planet dubbed SPECULOOS-2c that’s precariously close to its star. She and her colleagues completed an analysis, uploaded as a preprint in September, showing that SPECULOOS-2c’s water could be in the process of steaming away like sauna vapor, as any seas of Venus did long ago and as Earth’s own oceans will begin to do in half a billion years. Telescope observations should be able to tell within a few years if that’s happening, which will help reveal our own planet’s future and further demarcate the knife’s-edge distinction between hostile and habitable worlds across the galaxy.

"In simulating ersatz Earths and more speculative visions of living planets, Kaltenegger leverages the bizarre life and geology found on Earth to develop a more systematic set of expectations about what might be possible elsewhere. “I’m trying to do the fundamentals,” she told me during a recent visit to Cornell University, where she leads an institute named for Carl Sagan,

***

"...most astronomers believe that our best near-term chance of encountering other life in the cosmos is to detect biosignature gases — gases that could only have come from life — floating in exoplanets’ atmospheres. The sort of remote measurement necessary to make that kind of detection has strained the capabilities of even humanity’s most advanced observatories. But with the James Webb Space Telescope (JWST) now in its first few months of observations, such a discovery has become possible.

***

"Without a good theoretical model for how Earth’s own spectrum has changed, Kaltenegger feared, the big planet-finding missions could easily miss a living world that didn’t match a narrow temporal template. She needed to envision Earth as an exoplanet evolving through time. To do this, she adapted one of the first global climate models, developed by the geoscientist James Kasting, which still includes references to the 1970s magnetic-tape era it originated in. Kaltenegger developed this code into a bespoke tool that can analyze not only Earth through time but also radically alien scenarios, and it remains her lab’s workhorse.

***

"The first biosignatures will be tiny, ambiguous signals subjected to warring interpretations. In fact, some claims have already emerged.

"The most pertinent case study rocked the astronomy world in the fall of 2020. A team including Seager announced that they had spotted an unusual compound called phosphine in the upper atmosphere of Venus, a sweltering, acid-washed planet typically dismissed as sterile. On Earth, phosphine is commonly produced by microbes. While some abiotic processes can also make the compound under certain conditions, the team’s analysis suggested those processes weren’t likely to occur on Venus. In their view, that left tiny floating Venusian organisms as a plausible explanation. “Life on Venus?” the New York Times headline wondered.

"Outside groups formed opposing camps. Some experts, including Victoria Meadows, an exoplanet atmosphere modeler at the University of Washington who uses a similar approach to Kaltenegger’s, reanalyzed the Venus data and concluded that the phosphine signal was just a mirage: The chemical isn’t even there. Others, including Lunine at Cornell, argued that even if phosphine is present, it could, in fact, come from geologic sources.

Comment: so, no evidence so far. We live in a very specialized place. If God wanted life in any form elsewhere, it will be there.

3424 views

Possibly explained:

https://www.newscientist.com/article/2346067-we-may-finally-know-how-impossible-stars-a...

"The centre of our galaxy is home to a strange cohort of stars that should never have existed, and we may now know how they formed. The gravity in this area, next to the supermassive black hole at the middle of the Milky Way, is so powerful that it should disrupt any clouds dense enough to begin turning into stars, but the shock wave from another star’s violent demise could have given those nascent stars a window of opportunity.

"Most ideas to explain the existence of more than 100 young stars within a few light years of the Milky Way’s centre involve the stars forming elsewhere and then migrating inwards. But if that were the case, we would expect the stars to orbit within the disc of the galaxy, not misaligned from it as they appear to be.

"Rosalba Perna at Stony Brook University in New York and Evgeni Grishin at Monash University in Australia have come up with a different idea for how these unexpected stars may have formed. When a star wanders too close to a black hole, that star is ripped apart in what’s called a tidal disruption event (TDE). These events cause huge explosions and sometimes enormous jets with shock waves that propagate through the surrounding dust and gas.

"When the researchers calculated how one of these shock waves would affect the clouds of gas near the galactic centre, they found that it would compress the gas enough for it to hold together in the region’s intense gravity. After the shock wave compressed the gas by a factor of tens or even hundreds of millions, it would only be a matter of time before those clumps started to become stars, says Perna.

“'We know that explosive events have a feedback effect on star formation in other contexts,” she says. “As we were looking into the details of it here, all the numbers in terms of rates, energetics, length scales, they all just fell into place.”

"The expected rate of TDEs with jets near the galactic centre – about one every few million years – is similar to the age of these stars. Plus, the shock waves would not necessarily be aligned with the disc of the galaxy, so it makes sense that the stars would form outside of the galactic disc. The expected masses of the stars formed via this mechanism line up with the measured masses of the stars in this region, as well. Detailed simulations should help researchers determine whether the strange stars at the centre of our galaxy really do come from the shredding of less lucky stars, Perna says."

Comment: looks ilke a good guess.

3450 views

The GWB should be there:

https://www.sciencemagazinedigital.org/sciencemagazine/library/item/11_november_2022/40...

"Gravitational waves are ripples in the fabric of spacetime that are caused by events such as the merging of black holes. In principle, many types of events occur that could create gravitational waves with frequencies ranging from as high as a few kilohertz to as low as a few nanohertz. Sources of gravitational waves in the nanohertz frequency range include cosmic strings, quantum fluctuations from the early Universe, and, notably, supermassive black hole binaries (SMBHBs). Some gravitational wave sources are so numerous that they are all expected to contribute to a gravitational wave background (GWB). This GWB has been the target of pulsar timing arrays (PTAs) for decades.

"Some gravitational wave sources are so numerous that they are all expected to contribute to a gravitational wave background (GWB). This GWB has been the target of pulsar timing arrays (PTAs) for decades.

"PTAs use the correlations between dozens of pulsar pairs to observe the GWB. Recently, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) (1), the European Pulsar Timing Array (EPTA) (2), the Parkes Pulsar Timing Array (PPTA) (3), and the International Pulsar Timing Array (IPTA) (4) have all detected a low-frequency noise in their pulsar data, which may be the first hint of the GWB

***

"The noise in each pulsar should be independent, whereas the GWB signal should be a common signal in each pulsar—hence, the more pulsar pairs that can be observed, the lower the noise and the larger the signal. The smoking gun of the GWB is the Hellings and Downs curve (5), for which we expect the recently detected red noise to eventually conform to a specific functional form (see the figure).

***

"Although the focus is on SMBHBs because of their expected presence in the PTA frequency range, other sources are possible. A network of cosmic strings, the existence of which has never been directly demonstrated, is another potential source of a GWB. A third source, a GWB of primordial origin, would provide evidence of an ekpyrotic Universe, where the Big Bang is eventually followed by a Big Crunch. It is not known for sure how long it will take to distinguish between different sources, but Pol et al. (8) showed that at the time of an initial detection of spatial correlations in pulsar pairs with a signal-to-noise ratio of three, current PTAs should have the capability to distinguish a SMBHB from at least some such exotic sources.

"Once the GWB is detected, the next task is to make maps of it, akin to the cosmic microwave background. For instance, individual nearby SMBHB systems and potentially large-scale structures could contribute to or trace the anisotropy in the GWB (12). Indeed, GWB anisotropy may enable us to constrain the cosmic population of SMBHBs. Moreover, it will be interesting to see where the anisotropic (excess) power on the sky originates and whether this can be associated with SMBHB activity. However, obtaining upperlimit maps of GWB anisotropy may be challenging because the distribution of pulsars in the sky is itself anisotropic, thwarting the use of the usual spherical harmonics (13).

***

"The detection of the GWB may be imminent, and as such, a new low-frequency era of GW astronomy is at hand. Assuming that the GWB is astrophysical, its detection will likely cast aside any remaining doubt that SMBHs do eventually merge. Moreover, it will yield insights into the expected number density of SMBHBs as a function of redshift, the volume enclosing the GWB, and the minimum mass of a SMBHB that contributes to the background (10). All these values are fundamental properties of SMBHBs on which there are extremely limited observational constraints (which also come from PTAs). At present, PTA datasets span about 15 years, and with 5 more years of data, it should be possible to measure a low-frequency turnover in the GWB strain spectrum due to the presence of, for example, gas and stars surrounding the cosmic population of SMBHBs (8). Underlying all of this exciting astrophysics will be IPTA datasets formed by combining data from all the major PTAs, substantially increasing detection prospects for all nanohertz gravitational wave sources."

Comment: the GWB background map will be a tremendous advance. It may settle the Hubble tension problem of theoretically two values that don't agree. It may settle the flatness issue of the shape of space time. To understand the technicalities at least look at the illustrations.

3403 views

Something is pulling the Milky Way in one direction:

https://www.universetoday.com/158434/chipping-away-at-the-great-attractor-mystery-anoth...

"Something huge lurks in the shadows of the Universe. Known as the Great Attractor, it is causing the Milky Way and all the surrounding galaxies to rush towards it. We would normally have a better understanding of this situation, except for the fact that the Great Attractor happens to lie in the direction behind the galactic bulge, which makes it difficult for us to observe. A team of astronomers have performed a new infrared survey of the region behind the bulge, and they have found yet another large galaxy cluster. Their work is helping to paint a more complete portrait of the environment of the Great Attractor.

"All galaxies in the Universe are in motion. At the very largest scales this motion is dominated by what astronomers call the Hubble flow, which is just the general expansion of the Universe. This causes most galaxies to recede away from each other. But at anything less than fully cosmological scales, there can be extra motion on top of that. For example, the Milky Way and the Andromeda galaxies are on a collision course, and they will merge together in about 5 billion years.

"In addition to that merger, our two galaxies, along with all the other galaxies in our local group, are rushing towards the Virgo cluster, which is the nearest cluster of galaxies to us.

"But it doesn’t stop there. The local group, the Virgo cluster, and all the other groups and clusters in the nearby region of space are headed in one direction together. Astronomers call the center point of this movement the Great Attractor, because it seems to be the largest source of gravity in our local cosmological environment.

"It just so happens by pure dumb luck that the Great Attractor sits in the direction of our sky behind the galactic bulge. This region of the sky is called the Zone of Avoidance, because it’s very difficult for optical telescopes to pierce the thick clouds of dust and gas in this region to develop a clear map of what’s behind it.

"Our only hope is to use other wavelengths of light that can penetrate gas and dust more easily. One of those wavelengths is infrared. But infrared surveys in this regime is a very difficult task, and so our maps in this region of the universe are incomplete.

"The team of astronomers have attempted a new survey of the region with the Gemini South Telescope, especially targeting a half dozen galaxies within the Zone of Avoidance. They found that the galaxies in their survey were likely to be associated with each other. It’s the first evidence we have that these galaxies might be a member of a much larger cluster of galaxies."

Comment: we are still learning a lot about our galactic neighborhood. Since I view the universe as God created, all of this has God's reasons behind it.

3410 views

Complete theory puts it at ten billion years:

https://www.sciencealert.com/scientists-figured-out-when-and-how-our-sun-will-die-and-i...

"How will our Sun look after it dies? Scientists have made predictions about what the final days of our Solar System will look like, and when it will happen. And we humans won't be around to see the Sun's curtain call.

"Previously, astronomers thought the Sun would turn into a planetary nebula – a luminous bubble of gas and cosmic dust – until evidence suggested it would have to be a smidge more massive.

"An international team of astronomers flipped it again in 2018 and found that a planetary nebula is indeed the most likely solar corpse.

"The Sun is about 4.6 billion years old – gauged on the age of other objects in the Solar System that formed around the same time. Based on observations of other stars, astronomers predict it will reach the end of its life in about another 10 billion years.

"There are other things that will happen along the way, of course. In about 5 billion years, the Sun is due to turn into a red giant. The core of the star will shrink, but its outer layers will expand out to the orbit of Mars, engulfing our planet in the process. If it's even still there.

"One thing is certain: By that time, we won't be around. In fact, humanity only has about 1 billion years left unless we find a way off this rock. That's because the Sun is increasing in brightness by about 10 percent every billion years.

That doesn't sound like much, but that increase in brightness will end life on Earth. Our oceans will evaporate, and the surface will become too hot for water to form. We'll be about as kaput as you can get.

"There are other things that will happen along the way, of course. In about 5 billion years, the Sun is due to turn into a red giant. The core of the star will shrink, but its outer layers will expand out to the orbit of Mars, engulfing our planet in the process. If it's even still there.

"One thing is certain: By that time, we won't be around. In fact, humanity only has about 1 billion years left unless we find a way off this rock. That's because the Sun is increasing in brightness by about 10 percent every billion years.

"That doesn't sound like much, but that increase in brightness will end life on Earth. Our oceans will evaporate, and the surface will become too hot for water to form. We'll be about as kaput as you can get.

"There are other things that will happen along the way, of course. In about 5 billion years, the Sun is due to turn into a red giant. The core of the star will shrink, but its outer layers will expand out to the orbit of Mars, engulfing our planet in the process. If it's even still there.

***

"The data model that the team created actually predicts the life cycle of different kinds of stars, to figure out the brightness of the planetary nebula associated with different star masses.

"Planetary nebulae are relatively common throughout the observable Universe, with famous ones including the Helix Nebula, the Cat's Eye Nebula, the Ring Nebula, and the Bubble Nebula.

***

"Almost 30 years ago, astronomers noticed something peculiar: The brightest planetary nebulae in other galaxies all have about the same level of brightness. This means that, theoretically at least, by looking at the planetary nebulae in other galaxies, astronomers can calculate how far away they are.

***

"'The data said you could get bright planetary nebulae from low mass stars like the Sun, the models said that was not possible, anything less than about twice the mass of the Sun would give a planetary nebula too faint to see."

"The 2018 models have solved this problem by showing that the Sun is about the lower limit of mass for a star that can produce a visible nebula.

***

"'This is a nice result," Zijlstra said. "Not only do we now have a way to measure the presence of stars of ages a few billion years in distant galaxies, which is a range that is remarkably difficult to measure, we even have found out what the Sun will do when it dies!'"

Comment we won't be here to see it. This fits Adler's thought that God really caring about us is only a 50/50 chance.

3418 views

In simple language:

https://www.quantamagazine.org/

"But this mismatch between intuition and theory makes the leap to a space-time perspective somewhat intimidating. What’s worse, presentations of relativity often take a bottom-up approach — they start with our everyday conceptions of space and time and alter them in the new context of relativity.

"We’re going to be a little different. Our route into special relativity might be thought of as top-down, taking the idea of a unified space-time seriously from the get-go and seeing what that implies. We’ll have to stretch our brains a bit, but the result will be a much deeper understanding of the relativistic perspective on our universe.

***

"Einstein’s theory came to be known as the special theory of relativity, or simply special relativity. In his foundational paper, “On the Electrodynamics of Moving Bodies,” he argued for new ways of thinking about length and duration. He explained the special role of the speed of light by positing that there is an absolute speed limit in the universe — a speed at which light just happens to travel when moving through empty space — and that everyone would measure that speed to be the same, no matter how they were moving. To make that work out, he had to alter our conventional notions of time and space.

"But he didn’t go quite so far as to advocate joining space and time into a single unified space-time. That step was left to his former university professor, Hermann Minkowski, in the early 20th century. The arena of special relativity is today known as Minkowski space-time.

"Once you have the idea of thinking of space-time as a unified four-dimensional continuum, you can start asking questions about its shape. Is space-time flat or curved, static or dynamic, finite or infinite? Minkowski space-time is flat, static and infinite.

"Einstein worked for a decade to understand how the force of gravity could be incorporated into his theory. His eventual breakthrough was to realize that space-time could be dynamic and curved, and that the effects of that curvature are what you and I experience as “gravity.” The fruits of this inspiration are what we now call general relativity.

"So special relativity is the theory of a fixed, flat space-time, without gravity; general relativity is the theory of dynamic space-time, in which curvature gives rise to gravity.

Comment: Sean Carroll then explains how to think about spacetime. Read it for clarity.

3390 views

Collapsed extremely dense stars:

https://www.sciencealert.com/wild-new-study-reveals-neutron-stars-are-actually-like-a-b...

"Life isn't really like a box of chocolates, but it seems that something out there is. Neutron stars – some of the densest objects in the Universe – can have structures very similar to chocolates, with either gooey or hard centers.

"What kinds of particle configurations those centers consist of is still unknown, but new theoretical work revealing this surprising result could put us a step closer to understanding the strange guts of these dead stars, and the wild extremes possible in our Universe.

"Neutron stars are pretty incredible. If we consider black holes to be objects of immense (if not infinite) concentrations of matter, neutron stars win second place in the Universe's Most Dense Award. Once a star with a mass of around 8 to 30 times that of the Sun's runs out of matter to fuse in its core, it's no longer supported by heat's outward pressure, allowing the core to collapse under gravity as its shell of surrounding gases drift off into space.

"The resulting neutron star has a reduced mass of up to around 2.3 times the mass of the Sun, but it's squeezed into a sphere around just 20 kilometers (12 miles) across. These things are capital-letters DENSE – and what exactly happens to matter under such mind-blowing pressures is something scientists are dying to know.

"Some studies propose that nuclei crowd together until they form shapes that resemble pasta. Others suggest even deeper inside the star, pressures become so extreme that atomic nuclei cease to exist altogether, condensing into a "soup" of quark matter.

"Now, theoretical physicists led by Luciano Rezzolla of Goethe University in Germany have discovered how neutron stars might be akin to chocolates with different fillings.

"When the team used their equations of state to study the speed of sound in neutron stars, their structures were not uniform across the board. Rather, the neutron stars on the lower end of the mass range, below 1.7 times the mass of the Sun, seemed to have a squishy mantle and harder core, while those above 1.7 solar masses had a hard mantle and a squishy core.

"'This result is very interesting because it gives us a direct measure of how compressible the center of neutron stars can be," Rezzolla says.

"'Neutron stars apparently behave a bit like chocolate pralines: light stars resemble those chocolates that have a hazelnut in their center surrounded by soft chocolate, whereas heavy stars can be considered more like those chocolates where a hard layer contains a soft filling."

"This seems to fit with both the nuclear pasta and quark soup interpretations of neutron star innards, but it also provides new information that could help model neutron stars across a range of masses in future work.

"This could also explain how, regardless of their masses, all neutron stars have roughly the same diameter of around 20-kilometers.

"'Our extensive numerical study not only allows us to make predictions for the radii and maximum masses of neutron stars, but also to set new limits on their deformability in binary systems, that is, how strongly they distort each other through their gravitational fields," says physicist Christian Ecker of the University of Goethe."

Comment: until we figure it out, it will be approached as weird. And I'd better repeat my view. If God did it, it had to be there for reasons God felt were reasonable.

3383 views

A current view of our neighbor:

https://phys.org/news/2022-11-dark-stream-life-galaxies.html

"An international team of scientists led by a University of Sydney astrophysicist has discovered evidence the Andromeda galaxy is a cannibal growing through colossal intermittent feasts.

"' few years ago, we discovered that in the far outskirts of Andromeda, there was a sign in the objects orbiting it that the galaxy hadn't been grazing, but it had eaten large quantities in two distinct epochs," said lead author Professor Geraint Lewis from the University of Sydney.

"'What this new result does is provide a clearer picture of how our local universe has come together—it is telling us that at least in one of the large galaxies, that there has been this sporadic feeding of small galaxies."

"The research findings are based on the discovery of a structure of stars, known as globular clusters, in Andromeda that originated outside the galaxy. Professor Lewis named this the Dulais Structure, drawn from the Welsh for black stream.

"The Dulais Structure represents the leftovers of a colossal feeding event in the "recent" past, a dark stream lit up by star clusters orbiting unlike any others in Andromeda. It provides evidence that galaxies grow by "eating" smaller systems, and the findings are at odds with a more sedate picture of galactic growth.

"'That then leads to the next question of, well, what was actually consumed? Because it doesn't look like it was just one thing, it looks like it's been a collection of things which are all being slowly torn apart," said Professor Lewis. "We've come to realize over the last few decades that galaxies grow by eating smaller systems—so little galaxies fall in, they get eaten—it's galactic cannibalism."

"Andromeda has the signatures of two major feeding events. Rough timescales indicate the "recent" feast took place sometime in the last 5 billion years, while the older feed was closer to 8–10 billion years ago. The universe itself is 13.8 billion years old, meaning the two separate events may have taken place while matter in the universe was in closer proximity and more densely concentrated.

***

"It is unclear how the Milky Way itself has fed, but a picture is emerging in Andromeda with a clear signature—large feasts and growth spurts. Given the Milky Way is a spiral galaxy of similar size, the research may be painting a picture of what our galaxy has done to reach its enormous size.

"'What we want to know is has the Milky Way done the same, or is it different? Both of those have interesting consequences for the overall picture of how galaxies form," Professor Lewis said. "We want to, at some level, come up with a more accurate clock to tell us when these events occurred because that's one thing we need to include in our models of how galaxies evolve."

"He and colleagues analyzed data covering the speeds and chemistry of the globular clusters forming the Dulais Structure, providing a two-dimensional view. The next step is to understand distances, which will allow researchers to construct the history in three dimensions.

"'That will then allow us to work out orbits, where things are going, and then we can start to run the clock backwards and see if we can get this coherent picture of when things fell in," he said.

"'We couldn't name it as an object like a galaxy, because we actually do not know if the signature we see is from one big object disrupting or seven smaller objects disrupting. That's why we sort of refer to it as a structure rather than it being a particular galaxy.'"

Comment: we have had much evidence of the Milk Way absorbing local small galaxies. Could we have gobbled up a big one? It seems big spiral galaxies are cannibalistic.

3400 views

New calculations:

https://www.quantamagazine.org/why-this-universe-new-calculation-suggests-our-cosmos-is...

"...two physicists have turned the conventional thinking about our vanilla universe on its head. Following a line of research started by Stephen Hawking and Gary Gibbons in 1977, the duo has published a new calculation suggesting that the plainness of the cosmos is expected, rather than rare. Our universe is the way it is, according to Neil Turok of the University of Edinburgh and Latham Boyle of the Perimeter Institute for Theoretical Physics in Waterloo, Canada, for the same reason that air spreads evenly throughout a room: Weirder options are conceivable, but exceedingly improbable.

***

"The provocative conclusion rests on a mathematical trick involving switching to a clock that ticks with imaginary numbers. Using the imaginary clock, as Hawking did in the ’70s, Turok and Boyle could calculate a quantity, known as entropy, that appears to correspond to our universe. But the imaginary time trick is a roundabout way of calculating entropy, and without a more rigorous method, the meaning of the quantity remains hotly debated. While physicists puzzle over the correct interpretation of the entropy calculation, many view it as a new guidepost on the road to the fundamental, quantum nature of space and time.

“'Somehow,” Gielen said, “it’s giving us a window into perhaps seeing the microstructure of space-time.”

***

"...they turned to a technique developed in the 1940s by the physicist Richard Feynman.

"Aiming to capture the probabilistic behavior of particles, Feynman imagined that a particle explores all possible routes linking start to finish: a straight line, a curve, a loop, ad infinitum. He devised a way to give each path a number related to its likelihood and add all the numbers up. This “path integral” technique became a powerful framework for predicting how any quantum system would most likely behave.

"As soon as Feynman started publicizing the path integral, physicists spotted a curious connection with thermodynamics, the venerable science of temperature and energy. It was this bridge between quantum theory and thermodynamics that enabled Turok and Boyle’s calculation.

***

"Entropy gives physicists a sharp way of comparing the odds of different outcomes: The higher the entropy of a macrostate, the more likely it is. There are vastly more ways for air molecules to arrange themselves throughout the whole room than if they’re bunched up in a corner, for instance. As a result, one expects air molecules to spread out (and stay spread out). The self-evident truth that probable outcomes are probable, couched in the language of physics, becomes the famous second law of thermodynamics: that the total entropy of a system tends to grow.

***

"By Wick-rotating the roller-coaster expansion history of a more realistic class of universes, they got a more versatile equation for cosmic entropy. For a wide range of cosmic macrostates defined by radiation, matter, curvature and a dark energy density (much as a range of temperatures and pressures define different possible environments of a room), the formula spits out the number of corresponding microstates. Turok and Boyle posted their results online in early October.

"Experts have praised the explicit, quantitative result. But from their entropy equation, Boyle and Turok have drawn an unconventional conclusion about the nature of our universe. “That’s where it becomes a little more interesting, and a little more controversial,” Hertog said.

Boyle and Turok believe the equation conducts a census of all conceivable cosmic histories. Just as a room’s entropy counts all the ways of arranging the air molecules for a given temperature, they suspect their entropy counts all the ways one might jumble up the atoms of space-time and still end up with a universe with a given overall history, curvature and dark energy density.

**

"Their census reveals that the overwhelming majority of the marbles [universes] have just one color — blue, say — corresponding to one type of universe: one broadly like our own, with no appreciable curvature and just a touch of dark energy. Weirder types of cosmos are vanishingly rare. In other words, the strangely vanilla features of our universe that have motivated decades of theorizing about cosmic inflation and the multiverse may not be strange at all.

***

“'What our calculation does is provide huge extra motivation for people who are trying to build microscopic theories of quantum gravity,” Turok said. “Because the prospect is that that theory will ultimately explain the large-scale geometry of the universe.'”

Comment: Only one possible universe? Which is fine-tuned for life. From one Big Bang. More evidence of a designer universe.

3388 views

The telescope is seeing the formation of early galaxies occurs at high speed:

https://phys.org/news/2022-11-webb-space-telescope-reveals-birth.html

"The earliest galaxies were cosmic fireballs converting gas into stars at breathtaking speeds across their full extent, reports a UCLA-led study to be published in a special issue of The Astrophysical Journal.

"The research, based on data from the James Webb Space Telescope, is the first study of the shape and structure of those galaxies. It shows that they were nothing like present-day galaxies in which star formation is confined to small regions, such as the constellation of Orion in our own Milky Way galaxy.

***

"'Webb's incredible resolution allows us to study these galaxies in unprecedented detail, and we see all of this star formation occurring within the regions of these galaxies."

***

"Webb is the largest near-infrared telescope in space, and its remarkable resolution offers an unparalleled view of objects so distant that their light takes billions of years to reach Earth. Although those objects have aged by now, light from only their earliest moments has had enough time to travel through the universe to end up on Webb's detectors. As a result, not only has the Webb functioned as a sort of time machine—taking scientists back to the period shortly after the Big Bang—but the images it's producing have become a family album, with snapshots of infant galaxies and stars.

***

"The project seeks to understand how and when light from the first galaxies burned through the hydrogen fog left over from the Big Bang—a phenomenon and time period called the Epoch of Reionization—and how gas and heavy elements are distributed within and around galaxies over cosmic time. Treu and Roberts-Borsani use three of the Webb's innovative near-infrared instruments to take detailed measurements of distant galaxies in the early universe.

"The Epoch of Reionization is a period that remains poorly understood by scientists. Until now, researchers have not had the extremely sensitive infrared instruments needed to observe galaxies that existed then. Prior to cosmic reionization, the early universe remained devoid of light because ultraviolet photons from early stars were absorbed by the hydrogen atoms that saturated space.

"Scientists think that sometime within the universe's first billion years radiation emitted by the first galaxies and possibly by the first black holes caused the hydrogen atoms to lose electrons, or ionize, preventing photons from "sticking" to them and clearing a pathway for the photons to travel across space. As galaxies began to ionize larger and larger bubbles, the universe became transparent and light traveled freely, as it does today, allowing us to view a brilliant canopy of stars and galaxies each night.

"Roberts-Borsani's finding that galaxies formed faster and earlier than previously thought could confirm that they were the culprits of cosmic reionization. The study also confirms the distances to two of the farthest galaxies known using a new technique that allows astronomers to probe the beginning of cosmic reionization.

Comment: this helps outline the evolution of the universe after the Big Bang, showing the 'how' but not the 'why' of the process.

3392 views

Radio astronomy finds them:

https://phys.org/news/2022-11-milky-mysterious-filaments-older-distant.html

"Northwestern University astrophysicist Farhad Zadeh has been fascinated and puzzled by a family of large-scale, highly organized magnetic filaments dangling in the center of the Milky Way ever since he first discovered them in the early 1980s.

Now, 40 years later, Zadeh remains just as fascinated—but perhaps slightly less puzzled.

"With a new discovery of similar filaments located in other galaxies, Zadeh and his collaborators have, for the first time, introduced two possible explanations for the filaments' unknown origins. In a new paper, published earlier this month in The Astrophysical Journal Letters, Zadeh and his co-authors propose the filaments might result from an interaction between large-scale wind and clouds or could arise from turbulence inside a weak magnetic field.

"'We know a lot about the filaments in our own Galactic Center, and now filaments in outside galaxies are beginning to show up as a new population of extragalactic filaments," Zadeh said. "The underlying physical mechanisms for both populations of filaments are similar despite the vastly different environments. The objects are part of the same family, but the filaments outside the Milky Way are older, distant cousins—and I mean very distant (in time and space) cousins."

"An expert in radio astronomy, Zadeh is a professor of physics and astronomy in Northwestern's Weinberg College of Arts and Sciences and a member of the Center for Interdisciplinary Exploration and Research in Astrophysics

"The first filaments that Zadeh discovered stretched up to 150 light years long, towering near the Milky Way's central supermassive black hole. Earlier this year, Zadeh added nearly 1,000 more filaments to his collection of observations. In that batch, the one-dimensional filaments appear in pairs and clusters, often stacked equally spaced, side by side like strings on a harp or spilling sideways like individual ripples in a waterfall.

"Using observations from radio telescopes, Zadeh discovered the mystifying filaments comprise cosmic ray electrons gyrating along a magnetic field at close to the speed of light. Although he is putting together the puzzle of what the filaments are made of, Zadeh still wondered where they came from. When astronomers discovered a new population outside our own galaxy, it offered new opportunities to investigate the physical processes in the space surrounding the filaments.

"The newly discovered filaments reside inside a galaxy cluster, a concentrated tangle of thousands of galaxies located one billion light-years from Earth. Some of the galaxies within the cluster are active radio galaxies, which appear to be breeding grounds for the for formation of large-scale magnetic filaments. When Zadeh saw these newly uncovered filaments for the first time, he was amazed.

"'After studying filaments in our own Galactic Center for all these years, I was extremely excited to see these tremendously beautiful structures," he said. "Because we found these filaments elsewhere in the universe, it hints that something universal is happening."

***

"In the new paper, Zadeh and his collaborators hypothesize that the filaments' origins could be a simple interaction between galactic wind and an obstacle, such as a cloud. As the wind wraps around the obstacle, it creates a comet-like tail behind it.

""Wind comes from the motion of the galaxy itself as it rotates," Zadeh explained. "It's like when you stick your hand out of a window from a moving car. There's no wind outside, but you feel the air moving. When the galaxy moves, it creates wind that could be pushing through places where the cosmic ray particles are fairly loose. It sweeps the material and creates a filamentary structure. "

***

"'All of these filaments outside our galaxy are very old," he said. "They are almost from a different era of our universe and yet signaling the Milky Way inhabitants that a common origin exists for the formation of the filaments. I think this is remarkable.'"

***

Comment: a striking discovery. See the photos to appreciate. This is a side-effect from other processes according to his discussion.

3482 views

A thorough explanation of the estimated age:

https://bigthink.com/starts-with-a-bang/universe-13-8-billion-years-302173/?utm_source=...

"We now state, with confidence, that the Universe is 13.8 billion years old. But how confident can we really be in that answer?

***

"The simplest and most straightforward way to measure the age of the Universe is simply to look at the objects that are in it: stars, for instance. We have hundreds of billions of stars in the Milky Way galaxy alone, and the overwhelming majority of the ancient history of astronomy was devoted to studying and characterizing stars. It remains an active field of research today, as astronomers have uncovered the relationship between observed properties of stellar populations and how old they are.

***

"...when we look at a population of stars, we can tell how old it is by looking at what types stars still remain, and what classes of stars are completely gone.

***

"Today, we can reliably conclude there’s a lower limit to the age of the Universe of around 12.5-to-13 billion years from the stars we measure, but that doesn’t pin down the age precisely. It’s a good constraint to have, but to arrive at an actual figure, we’d like a better method.

***

"Observations ranging from the abundances of the light elements to the clustering of galaxies to how galaxy clusters collide to distant supernovae to the fluctuations in the cosmic microwave background all point toward the same Universe. In particular, it’s made up of:

"68% dark energy,
27% dark matter,
4.9% normal matter (protons, neutrons, and electrons),
0.1% neutrinos,
0.01% photons (particles of light, or radiation),
and less than 0.4% of everything else, including spatial curvature, cosmic strings, domain walls, and other fanciful, exotic components.

***

"Beginning the early 2000s, and ever since, the best data we have comes from the Cosmic Microwave Background: first from WMAP, then from Planck, and, as of July 14, 2020, from the Atacama Cosmology Telescope as well.

"Those values have all converged on the same expansion rate: 68 km/s/Mpc, with an uncertainty of just 1–2%. When you calculate what that means for the age of the Universe, you get a very robust 13.8 billion years, completely consistent with everything we know about stars.

***

"What’s fascinating about this, however, is that the derived age barely changes at all; if you explore the full range of what is and isn’t allowed, that 13.8 billion year old figure only comes along with an uncertainty of about 1%: between 13.67 and 13.95 billion years.

***

"...the data we have is all consistent with one particular age of the Universe: 13.8 billion years, with an uncertainty of only 1% on that value. It cannot be a billion years older or younger than this figure, not unless a whole host of things that we’ve measured have driven us to wildly incorrect conclusions. Unless the cosmos is lying to us, or we’re unwittingly fooling ourselves, what we know of as the hot Big Bang occurred between 13.67 and 13.95 billion years ago: no less and no more. Don’t believe any claims to the contrary without comparing them to the full suite of data!"

Comment: very thorough article. I've had to skip over man examples of measurements. Does not answer the question of the cause of the origin of the universe. And the universe evolved until now. It in one of the several evolutions God managed/created

3402 views

There have been bad ones:

https://bigthink.com/starts-with-a-bang/vulnerable-solar-flare/?utm_source=mailchimp&am...

"In 1859, the most powerful geomagnetic storm ever recorded occurred on Earth: triggered by a powerful solar flare that occurred ~17 hours prior. Although no biological creatures were directly harmed, all sorts of electrified devices, including power lines and telegraph wires, experienced surges and caught fire. A similar flare, today, would be a multi-trillion dollar disaster, and could lead to millions of deaths due to lack of heat, power, and food/water. But that's not even the worst-case scenario.

***

“'How concerned should I be for another Carrington-magnitude event?”

"On a daily basis, there are worse things to worry about. But over the coming years and decades, not only is a direct hit from a catastrophic space weather event inevitable, but a Carrington-like event isn’t even the worst case scenario. Here’s what everyone should know.

***

"Solar flares and coronal mass ejections consist of fast-moving charged particles from the sun: largely protons and other atomic nuclei. Normally, the sun emits a constant stream of these particles, known as the solar wind. However, these space weather events — in the form of solar flares and coronal mass ejections — can not only greatly enhance the density of charged particles that get sent out from the Sun, but their speed and energy as well. They typically occur close to equatorial latitudes, which means they’re at risk of intercepting the Earth. The Sun makes a full rotation every 25 days at its equator, while Earth orbits the Sun every ~365 days. When a flare or ejection is aligned with Earth, our planet is at risk.

"Given that we now have Sun-monitoring satellites and observatories, they’re our first line of defense: to alert us when a space weather event is potentially threatening to us. That occurs when a flare points directly at us, or when a coronal mass ejection appears “annular,” meaning that we only see a spherical halo of an event that’s potentially directed right at us.

***

"In fact, we’re only in trouble if three things all occur at once:

"The space weather events that occur need to have the proper magnetic alignment with respect to our own planet to penetrate our magnetosphere. If the alignment is off, Earth’s magnetic field will harmlessly deflect the majority of particles away, leaving the remainder to do nothing more than create a mostly harmless auroral display. This alignment occurs rarely, and can now be measured with the NSF’s Daniel K. Inouye Solar Telescope.

"Typical solar flares occur only at the Sun’s photosphere, but ones that interact with the solar corona — often connected by a solar prominence — can cause a coronal mass ejection. If a coronal mass ejection is directed right at Earth, and the particles are moving rapidly, that’s what puts Earth in the greatest amount of peril.

"There needs to be a large amount of electrical infrastructure in place, particularly large-area loops and coils of wire. Back in 1859, electricity was still relatively novel and rare; today, it’s a ubiquitous part of our global infrastructure. As our power grids become more interconnected and far-reaching, our infrastructure faces greater and greater threats from these space weather events.

***

"But today, with the massive amounts of electricity-based infrastructure that now covers our planet, the danger is very, very real.

"The problem comes from having long wires, loops and coils of wires, transformers, and similar electric/electronic infrastructure that current flows through. Whenever current flows, it creates a magnetic field; whenever the magnetic field through a loop or coil (or around a wire) changes, it can similarly induce an electric current. That’s where the danger comes in: the space weather events strike Earth, impact and alter our planet’s magnetic field at its surface, which causes the magnetic field to change in this electric/electronic infrastructure, causing charge to flow and inducing an electric current. Importantly, this occurs even if: there’s no battery, no voltage source, and even if the electronic devices are unplugged entirely.

"That’s what makes space weather so dangerous to us here on Earth: not that it poses a direct threat to humans, but that it can cause enormous amounts of electrical current to flow through the wires connecting our infrastructure. This can lead to:

" electrical shorts, fires, explosions, blackouts and power outages, a loss of communications infrastructure, and many other damages that will result as downstream consequences of this disruption. Consumer electronics aren’t a major problem; if you knew a solar storm was coming and you unplugged everything in your home, most of your devices would be safe. The major issue is with the infrastructure set up for large-scale production and transmission of power; there will be uncontrollable surges that will knock out power stations and substations and pump far too much current into cities and buildings."

Comment: you can imagine the damage he describes. The Carrington was over 156 years ago. dhw who will comment, about a 'bad' God who designed and allowed this problem. My response is easy. There is life here, and probably nowhere else. What is here and now was required to be here to allow life to arrive.

3372 views

How contrary:

https://www.newscientist.com/article/2349359-why-the-laws-of-physics-dont-actually-exist/

"First things first. What we often call laws of physics are really just consistent mathematical theories that seem to match some parts of nature. This is as true for Newton’s laws of motion as it is for Einstein’s theories of relativity, Schrödinger’s and Dirac’s equations in quantum physics or even string theory. So these aren’t really laws as such, but instead precise and consistent ways of describing the reality we see. This should be obvious from the fact that these laws are not static; they evolve as our empirical knowledge of the universe improves.

***

"There are around 86 billion neurons in the human brain. This is less than the number of stars in the Milky Way which is just a miniscule part of the known universe. The universe seems almost infinite in comparison to the finite capacity of the human brain, leaving us perhaps little chance of figuring out ultimate laws. What is amazing is that we can make sense of some aspects of the universe through the laws of physics. It may have been Richard Feynman who first said that the issue is not how clever we humans are in figuring out how nature works, it is how clever nature is in following our laws!

***

"Take string theory as an example. It is a theory that is very mathematically tight and rather magical in the way that it treats gravity and quantum mechanics equivalently, matching many of our observations of the universe. It holds a lot of promise, but so far has struggled to provide any testable concrete predictions beyond our current understanding.

"It also has a rather thorny stumbling block known as the landscape problem, where literally zillions of universes (around 10500, the number is so large that it seems obscene) are acceptable solutions of the theory. If string theory is correct one can declare victory as one of those zillions of universes must be our universe, and all one needs to do is to somehow find that particular solution to figure out what the laws of physics are for us. Of course, this is an impossible task because of the exceptionally large number of possible universes existing in the landscape, and all with their own distinct laws.

"This scenario is often called the multiverse. All possible laws, conceivable and inconceivable, are allowed in some possible universe, and laws of physics are no longer meaningful or unique from a fundamental sense, since they depend entirely on where in the multiverse landscape one is looking. It is ironic that the theory of everything turned out to imply an everything which is exponentially larger than any everything anybody could have imagined before.

***

"As a theoretical condensed matter physicist I do not find this scenario discouraging at all – quite the opposite. The fact that there is an essentially infinite number of possible laws only makes doing science more exhilarating because exploring the landscape will remain an active and creative activity forever. Theoretical physics can never end because the landscape is simply too vast.

"I know from my 40 years of experience in working on real-life physical phenomena that the whole idea of an ultimate law based on an equation using just the building blocks and fundamental forces is unworkable and essentially a fantasy. We never know precisely which equation describes a particular laboratory situation. Instead, we always have to build models and approximations to describe each phenomenon even when we know that the equation controlling it is ultimately some form of the Schrödinger equation!

***

"For example, the standard model of particle physics, the theory of superconductivity and the theory of atomic spectra are all built using the rules of quantum mechanics, but they have little to do with each other. In addition, space and time are variables that have to be put in by hand into the theory, when space and time should come out naturally from any ultimate law of physics. This has remained perhaps the greatest mystery in fundamental physics with no solution in sight.

***

"Newton’s laws were extraordinarily successful for 300 years, but we had to go beyond them as we learned more about the universe, and the same should happen with quantum laws some day in the future.

"Any such unknown new theory of the future must build on and incorporate the physics of quantum mechanics, just as quantum mechanics built on and incorporated classical mechanics. Our understanding of the physical world must continue indefinitely, unimpeded by the search for ultimate laws. Laws of physics continuously evolve – they will never be ultimate."

Comment: the thermodynamic law of entropy is so general it will always survive. On the other hand, he is right. Most other equations are simply descriptive of or current knowledge. Interesting to note, he is down the rabbit hole of string theory, because of its math beauty, which runs into the mess of multiverse requirements. Never to be solved.

3355 views

The tension is from two differing results of estimates of universal expansion:

https://www.universetoday.com/158738/early-dark-energy-could-explain-the-crisis-in-cosm...

"Since then, astronomers have looked farther into space (and hence, back in time) to measure how fast the Universe is expanding – aka. the Hubble Constant. These measurements have become increasingly accurate thanks to the discovery of the Cosmic Microwave Background (CMB) and observatories like the Hubble Space Telescope.

"Astronomers have traditionally done this in two ways: directly measuring it locally (using variable stars and supernovae) and indirectly based on redshift measurements of the CMB and cosmological models. Unfortunately, these two methods have produced different values over the past decade. As a result, astronomers have been looking for a possible solution to this problem, known as the “Hubble Tension.” According to a new paper by a team of astrophysicists, the existence of “Early Dark Energy” may be the solution cosmologists have been looking for.

***

"The direct method involves using supernovae as “standard candles” (distance markers) to conduct measurements on the local scale. The indirect method involves comparing measurements of the CMB with cosmological models – like the Lambda Cold Dark Matter (LCMD) model, which includes the presence of Dark Matter and Dark Energy. Unfortunately, these two methods produce different results, the former yielding a value of ~73 km/s per megaparsec (Mpc) and the latter yielding ~67 km/s Mpc. As Dr. Reiss broke it down to Universe Today via email:

“'The Hubble constant is the present rate at which the Universe expands. The Hubble tension is a discrepancy in the value you find for the Hubble constant when you either measure the expansion rate as best you can at present or you predict the value it should have based on the way the Universe looked after the Big Bang coupled with a model of how the Universe should evolve. Its a problem because if these two ways do not agree, it makes us think we are misunderstanding something about the Universe.”

"But as Reiss adds, the mystery of the Hubble Tension is not as much of a problem as it is an opportunity for new discovery. So far, many candidates have been offered to explain the discrepancy, ranging from the existence of extra radiation, modified General Relativity (GR), Modified Newtonian Dynamics (MOND), primordial magnetic fields, or the existence of Dark Matter and Dark Energy during the early Universe that behaved in different ways. These can generally be divided into two categories: early-time (shortly after the Big Bang) and late-time solutions (more recently in cosmic history).

"Late-time solutions postulate that the energy density in the post-recombination Universe – when the ionized plasma of the early Universe gave rise to neutral atoms (ca. 300 000 years after the Big Bang) – is smaller than in the standard LCMB model. Early-time solutions, meanwhile, postulate that the energy density was somehow increased before recombination occurred so that the “sound horizon” (the comoving distance a sound wave could travel) is decreased. For the sake of their study, Kamionkowski and Kenan considered Early Dark Energy (EDE) as a potential candidate.

"As Reiss explained, the presence of EDE would have contributed about 10% of the total energy density of the Universe before recombination occurred. After recombination, the energy density would have decayed faster than other forms of radiation, thus leaving the late evolution of the Universe unchanged. “It would produce a burst of extra, unexpected expansion in the young Universe that, if we didn’t know about it, would cause the predicted value to underestimate the true value,” said Reiss.

"What makes EDE preferable to late-time solutions is how the latter implies the existence of a fluid that effectively creates energy out of nothing – which violates the strong energy condition predicted by GR. What’s more, such models are difficult to reconcile with the Cosmic Distance Ladder measurements of Cepheid variables and Type Ia supernovae in nearby galaxies (low-redshift targets) and Type Ia supernovae in distant galaxies (high-redshift). In short, solutions that involve modifications to early-Universe dynamics appear to be most consistent with established cosmological constraints.

"As they note, while there is a growing body of evidence that hints at the existence of EDE, our current measurements on the CMB are not precise and robust enough yet to distinguish EDE models from the standard LCDM model. What is needed, moving forward, are improved local measurements that will help refine the Hubble Constant and remove any systematic errors. Second, more precise measurements of CMB polarization on smaller angular scales are needed to test EDE and other new physics models."

Comment: These are interesting attempts to solve the problem by going back to early times and possibly correcting errors in interpenetrations of the CMB.

3393 views

A puzzle no more. Its plan is explained:

https://phys.org/news/2022-12-cosmological-enigma-milky-satellite-galaxies.html

"Astronomers say they have solved an outstanding problem that challenged our understanding of how the universe evolved—the spatial distribution of faint satellite galaxies orbiting the Milky Way.

"These satellite galaxies exhibit a bizarre alignment—they seem to lie on an enormous thin rotating plane—called the "plane of satellites."

"This seemingly unlikely arrangement had puzzled astronomers for over 50 years, leading many to question the validity of the standard cosmological model that seeks to explain how the universe came to look as it does today.

"Now, new research jointly led by the Universities of Durham, U.K., and Helsinki, Finland, has found that the plane of satellites is a cosmological quirk which will dissolve over time in the same way that star constellations also change.

***

"The Milky Way's satellites seem to be arranged in an implausibly thin plane piercing through the galaxy and, oddly, they are also circling in a coherent and long-lived disk.

"There is no known physical mechanism that would make satellites planes. Instead, it was thought that satellite galaxies should be arranged in a roughly round configuration tracing the dark matter.

"Since the plane of satellites was discovered in the 1970s, astronomers have tried without success to find similar structures in realistic supercomputer simulations that track the evolution of the universe from the Big Bang to the present day.

***

"However, this latest research saw astronomers use new data from the European Space Agency's Gaia space observatory. Gaia is charting a six-dimensional map of the Milky Way, providing precise positions and motion measurements for about one billion stars in our galaxy (about 1% of the total), and its companion systems.

"These data allowed scientists to project the orbits of the satellite galaxies into the past and future and see the plane form and dissolve in a few hundred million years—a mere blink of an eye in cosmic time.

***

"They realized that previous studies based on simulations had been misled by failing to consider the distances of satellites from the center of the Galaxy, which made the virtual satellite systems appear much rounder than the real one.

"Taking this into account, they found several virtual Milky Ways which boast a plane of satellite galaxies very similar to the one seen through telescopes.

"The researchers say this removes one of the main objections to the validity of the standard model of cosmology and means that the concept of dark matter remains the cornerstone of our understanding of the universe.

***

"'But thanks to the amazing data from the Gaia satellite and the laws of physics, we now know that the plane is just a chance alignment, a matter of being in the right place at the right time, just as the constellations of stars in the sky.

"'Come back in a billion years, and the plane will have disintegrated, as will today's constellations.

"'We have been able to remove one of the main outstanding challenges to the cold dark matter theory. It continues to provide a remarkably faithful description of the evolution of our universe.'"

Comment: the faint galaxy satellite group feeds the Milky Way and makes it grow as our galaxy's gravity pulls them in.

3438 views

From yesterday's discussion:

"dhw: I can’t find the quote, but it makes no sense anyway...And why were the galaxies that had already disappeared during the 9 billion years that preceded our own all necessary for us to keep our feet on the ground? Perhaps you will now answer my bolded question.

"From the bold, how do you know galaxies disappear? The Milk Way is estimated as appearing in less than a billion years after the Big Bang, still here and active. The universe is in the business of creating stars which coalesce into galaxies.

Now:

https://www.universetoday.com/159329/webb-stares-deeply-into-the-universe-showing-how-g...

"True to its main science objectives, the JWST has peered back in time to the Universe’s earliest galaxies looking for clues to how they assemble and evolve.

"There’s only one way to understand the Universe and what led up to us, and everything else we can observe in the Universe. We have to somehow wind the clock back to long before the Earth, the Sun, our Solar System, or even the Milky Way existed in its present form. Fortunately, the Universe hasn’t expanded so much yet that all the other galaxies have disappeared over the observational horizon.

***

"The images show how the gravitational lensing from galaxy clusters in the foreground brings more distant objects into view. Some of the distant objects are ancient galaxies interacting with each other. Some of them are Active Galactic Nuclei, extremely luminous regions at the center of galaxies, where black holes superheat material that falls toward them. The AGN images should provide clues to how supermassive black holes (SMBHs) grow so large, an extremely active area of research.

***

"Research Scientist Rolf Jansen is one of the paper’s co-authors. He studies how the earliest galaxies formed and how they evolved into the forms they take today. “I was blown away by the first PEARLS images,” Jansen said. “Little did I know, when I selected this field near the North Ecliptic Pole, that it would yield such a treasure trove of distant galaxies and that we would get direct clues about the processes by which galaxies assemble and grow — I can see streams, tails, shells and halos of stars in their outskirts, the leftovers of their building blocks.”

***

“'With the enormous new range in both flux and wavelength that the JWST images provide, the community will now have the resources to expand and deepen the study of the morphology, SED (spectral energy distribution), star formation rates, masses, dust content, and extinction at redshifts extending to the epoch of first light, as well as better constrain how much diffuse light may be present in the infrared.”

"Young scientists just beginning their careers as the JWST begins its mission aren’t the only fortunate ones. For those of us who grew up on Hubble images, the James Webb is also a source of excitement and discovery. It’ll be fun watching as researchers working with Webb continue to make progress on some long-standing questions."

Comment: I've presented the true universe. After the Big Bang, it was about 300 million years until the first galaxies formed. It has been formation ever since. Galaxies don't just die. They can bump into each other and become absorbed. Yes, stars die, not galaxies. I have never found a description of a dying galaxy. The universe is alive in its own way, but gala xy death is not required. Look at the website, the images are mind-blowing.

3311 views

Ethan Siegel offers definitions:

https://bigthink.com/starts-with-a-bang/4-meanings-nothing/?utm_source=mailchimp&ut...

"All of the things that we see and experience in the Universe today have only been around for a finite amount of time. The Universe didn’t always have galaxies, stars, or atoms, and so they must have arisen at some point. But what did they come from? While the obvious answer might seem to be “something,” that’s not necessarily true; they may have arisen from nothing. What does “nothing” mean to a scientist in that context? Depending on who you ask, you might get one of four different answers. Here’s what they all mean.

"1.) A condition where the raw ingredients to create your “something” didn’t exist...how did we wind up with a matter-filled Universe, instead of one with equal amounts of matter and antimatter? That’s the first scientific meaning of getting something from nothing.

"2.) Nothingness is the void of empty space. Perhaps you prefer a definition of nothing that contains literally “no things” in it at all. If you follow that line of thinking, then the first definition is inadequate: it clearly contains “something.” In order to achieve nothingness, you’ll have to get rid of every fundamental constituent of matter. Every quantum of radiation has to go. Every particle and antiparticle, from the ghostly neutrino to whatever dark matter is, must be removed.

***

"If you could somehow remove them all — each and every one — you could ensure that the only thing that was left behind was empty space itself. With no particles or antiparticles, no matter or radiation, no identifiable quanta of any type in your Universe, all you’d have left is the void of empty space itself. To some, that’s the true scientific definition of “nothingness.”

***

"But certain physical entities still remain, even under that highly restrictive and imaginative scenario. The laws of physics are still there, which means that quantum fields still permeate the Universe. That includes the electromagnetic field, the gravitational field, the Higgs field, and the fields arising from the nuclear forces. Spacetime is still there, governed by General Relativity. The fundamental constants are all still in place, all with the same values we observe them to have.

***

"3.) Nothingness as the ideal lowest-energy state possible for spacetime. Right now, our Universe has a zero-point energy, or an energy inherent to space itself, that’s at a positive, non-zero value. We do not know whether this is the true “ground state” of the Universe, i.e., the lowest energy state possible, or whether we can still go lower. It’s possible that we’re in a false vacuum state, and that the true vacuum, or the true lowest-energy state, will either be closer to zero or may actually go all the way to zero.

***

"4.) Nothingness only occurs when you remove the entire Universe and the laws that govern it. This is the most extreme case of all: a case that steps out of reality — out of space, time, and physics itself — to imagine a Platonic ideal of nothingness. We can conceive of removing everything we can imagine: space, time, and the governing rules of reality. Physicists have no definition for anything here; this is pure philosophical nothingness.

"In the context of physics, this creates a problem: we cannot make any sense of this sort of nothingness. We’d be compelled to assume that there is such a thing as a state that can exist outside of space and time, and that spacetime itself, as well as the rules that govern all of the physical entities we know of, can then emerge from this hypothesized, idealized state.

***

"This final definition of nothing, while it certainly feels the most philosophically satisfying, may not have a meaning at all. It could just be a logical construct borne out of our inadequate human intuition.

***

"Each of the four definitions is correct in its own way, but what’s most important is understanding what the speaker means when they’re talking about their particular form of nothingness. Each definition has its own scope and range of validity, with applications to a wide range of particular physical problems, from the origin of matter to dark energy to cosmic inflation to the zero-point energy of space itself. But these concepts have a drawback as well: they’re all constructs of our own minds. Everything we know of certainly came from nothing. The key is to understand how."

Comment: As a pure scientist he is not allowed to jump to the obvious: God made it all from No. 4, pure nothingness. Of course, it "steps out of reality".

3359 views

In early period after the Big Bang collapse was possible, but Higgs may have prevented it:

https://www.newscientist.com/article/2183760-the-higgs-boson-may-have-stopped-the-early...

"The Higgs boson may be key to understanding the first moments of the universe. If the early universe was too disordered, everything would have collapsed into black holes moments after the big bang. Luckily, this didn’t happen, and some new calculations suggest the Higgs boson could be the reason why.

"Near the start of the beginning of the universe, everything was compressed into a very small space. Then, a process called inflation took over, rapidly expanding space to astronomical proportions.

"Most cosmologists agree that inflation happened, but it’s much less clear how. David Sloan at the University of Oxford, UK, and George Ellis at the University of Cape Town in South Africa have calculated that the Higgs boson may be the missing piece of the puzzle.

"Inflation requires a particular kind of particle that permeates every point in space, and the only such particle we’ve seen is the Higgs boson. According to Sloan and Ellis’s calculations, if the Higgs boson really is responsible, it would solve an important sticking point in our understanding of inflation – what the universe was like before it happened.

***

"We still don’t fully understand the Higgs boson, but one idea is that the its associated field is inversely correlated to gravity. In other words, as the strength of the Higgs field increases the strength of gravity decreases.

"Sloan and Ellis’s calculations show this would mean the black hole problem could be avoided entirely. As the Higgs field would have been stronger shortly after the big bang, gravity would have been much weaker, keeping matter from being crushed into black holes before inflation began to spread everything out.

"This is a big step beyond the standard model, but it’s plausible because of the ways we think gravity and the Higgs field interact now, says David Wands at the University of Portsmouth, UK.

"However, one downside of the idea is that we may never be able to test it. “Inflation is so extravagant in the amount of space that it produces that we only get to see a tiny portion of the whole universe as inflated,” says Wands. “It is hard to test these ideas about what happens before inflation in the patch of the universe that we see.”

"Sloan believes we shouldn’t write off testing the idea yet though as we may be able to see its effects in the areas of the current cosmos that are most like the super-dense pre-inflation universe, such as right outside of black holes, says Sloan.

Comment: the Higgs discovery is too recent to fully understand Higgs. Inflation is not proven, but it explains our current universe so well mostly all the cosmologists accept it.

3310 views

Thirty years of seeing other planetary models, none are like us:

https://www.sciencealert.com/weve-never-found-anything-like-the-solar-system-is-it-a-fr...

We've learnt many things from this vast catalogue of alien worlds orbiting alien stars. But one small detail stands out like a sore thumb. We've found nothing else out there like our own Solar System.

This has led some to conclude that our home star and its brood could be outliers in some way – perhaps the only planetary system of its kind.

"By extension, this could mean life itself is an outlier; that the conditions that formed Earth and its veneer of self-replicating chemistry are difficult to replicate.

***

"Most exoplanets we've seen so far orbit their stars very closely, practically hugging them; so close that their sizzling temperatures would be much higher than the known habitability range.

***

"Exoplanet science is limited by the capabilities of our technology. More than that, our impression of the true variety of alien worlds risks being limited by our own imagination.

"What's really out there in the Milky Way galaxy, and beyond, may be very different from what we actually see.

***

"By far, the most numerous group of exoplanets is a class that isn't even represented in the Solar System. That's the mini-Neptune – gas-enveloped exoplanets that are smaller than Neptune and larger than Earth in size.

"Most of the confirmed exoplanets are on much shorter orbits than Earth; in fact, more than half have orbits of less than 20 days.

"Most of the exoplanets we've found orbit solitary stars, much like our Sun. Fewer than 10 percent are in multi-star systems. Yet most of the stars in the Milky Way are members of a multi-star systems, with estimates as high as 80 percent seen in a partnership orbiting at least one other star.

"Think about that for a moment, though. Does that mean that exoplanets are more common around single stars – or that exoplanets are harder to detect around multiple stars? The presence of more than one source of light can distort or obscure the very similar (but much smaller) signals we're trying to detect from exoplanets, but it might also be reasoned that multi-star systems complicate planet formation in some way.

"And this brings us back home again, back to our Solar System. As odd as home seems in the context of everything we've found, it might not be uncommon at all."

Comment: it is just too soon to reach any conclusion. The technology needs further development.

3304 views

Follow up on DART:

https://www.sciencealert.com/nasa-slammed-a-spacecraft-into-an-asteroid-and-it-didnt-go...

"A series of five papers describing this course deflection, and the mechanisms behind it, have been published in Nature.

***

"One way we might deflect any large asteroids coming our way is by smashing into approaching rocks with a speeding spacecraft. The transfer of momentum from the spacecraft to the asteroid could alter its trajectory through space just enough to steer it away from its destiny with Earth's surface.

"The Double Asteroid Redirection Test (DART) was an attempt to see if this was feasible. The target was carefully chosen: Dimorphos, a moonlet orbiting a larger asteroid called Didymos. Because the orbital period of the two objects has been well characterized, any change in Dimorphos' trajectory would be detectable as a change in its orbital period.

***

"'DART's impact," they write, "demonstrates that the momentum transfer to a target asteroid can significantly exceed the incident momentum of the kinetic impactor, validating the effectiveness of kinetic impact for preventing future asteroid strikes on the Earth."

"Finally, a team led by planetary scientist Terik Daly of Johns Hopkins University Applied Physics Laboratory reconstructed the impact event from the collected data, including the timeline leading up to the impact, a detailed characterization of the impact site, and the size and shape of Dimorphos.

"Their findings are promising. Humanity can successfully deflect an asteroid from its course with limited knowledge of its composition and surface conditions, without conducting an expensive and lengthy reconnaissance mission first.

"An asteroid deflection mission, ideally, would be conducted decades in advance of the projected impact. Fortunately, time is a resource we have plenty of right now: no asteroids that we know of will threaten Earth for at least 100 years. This gives us time for a number of reconnaissance missions to any peripheral threats, which would improve the chances of successful deflection should anything change in the far future.

"In light of that, the information we have from DART is invaluable. It will contribute towards modeling and planning future asteroid deflections, if we need them, for better predictions of the outcomes of exploding spaceships into space rocks.

""The successful impact of the DART spacecraft with Dimorphos and the resulting change in Dimorphos's orbit," Daly and his team write, "demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary.'"

Comment: I assume God set up the universe the way it had to be as it evolved to allow the Earth to appear. Note how advanced humans have become to defend us from asteroids. And dhw doesn't think we are God's main purpose as we are here to defend everything God created on Earth. I can't change dhw's rigidity.

2369 views

Better definition of material parts:

https://www.quantamagazine.org/shadows-in-the-big-bang-afterglow-reveal-invisible-cosmi...

"The team carried out a series of analyses ranging from rock chemistry to microscopic bone structure. “The vertebrae turned out to be from a highly advanced, fast-growing, probably warm-blooded and fully oceanic ichthyosaur,” says [Benjamin] Kear [at Uppsala University].

Now they’re repurposing CMB data to catalog the large-scale structures that developed over "billions of years as the universe matured.

“'That light experienced a bulk of the history of the universe, and by seeing how it’s changed, we can learn about different epochs,” said Kimmy Wu, a cosmologist at SLAC National Accelerator Laboratory.

"Over the course of its nearly 14-billion-year journey, the light from the CMB has been stretched, squeezed and warped by all the matter in its way. Cosmologists are beginning to look beyond the primary fluctuations in the CMB light to the secondary imprints left by interactions with galaxies and other cosmic structures. From these signals, they’re gaining a crisper view of the distribution of both ordinary matter — everything that’s composed of atomic parts — and the mysterious dark matter.

***

"Standard optical surveys, which track the light emitted by stars, overlook most of the galaxies’ underlying mass. That’s because the vast majority of the universe’s total matter content is invisible to telescopes — tucked out of sight either as clumps of dark matter or as the diffuse ionized gas that bridges galaxies. But both the dark matter and the strewn gas leave detectable imprints on the magnification and color of the incoming CMB light.

“"The universe is really a shadow theater in which the galaxies are the protagonists, and the CMB is the backlight,” Schaan said.

***

"When light particles, or photons, from the CMB scatter off electrons in the gas between galaxies, they get bumped to higher energies. In addition, if those galaxies are in motion with respect to the expanding universe, the CMB photons get a second energy shift, either up or down depending on the relative motion of the cluster.

"This pair of effects, known respectively as the thermal and kinematic Sunyaev-Zel’dovich (SZ) effects, were first theorized in the late 1960s and have been detected with increasing precision in the past decade. Together, the SZ effects leave a characteristic signature that can be teased out of CMB images, allowing scientists to map the location and temperature of all the ordinary matter in the universe.

"Finally, a third effect known as weak gravitational lensing warps the path of CMB light as it travels near massive objects, distorting the CMB as though it were viewed through the base of a wineglass. Unlike the SZ effects, lensing is sensitive to all matter — dark or otherwise.

"Taken together, these effects allow cosmologists to separate the ordinary matter from the dark matter. Then scientists can overlay these maps with images from galaxy surveys to gauge cosmic distances and even trace star formation.

***

"The analysis showed that the region’s gas didn’t hug its supporting dark matter network as tightly as many models predicted. Instead, it suggests that blasts from supernovas and accreting supermassive black holes forced the gas away from its dark matter nodes, spreading it out so that it was too thin and cold for conventional telescopes to detect.

***

"..as theorized three decades ago by Sean Carroll and colleagues, that polarization could be rotated by a field of dark matter, dark energy, or some totally new particle. Such a field would cause photons of different polarizations to travel at different speeds and rotate the net polarization of the light, a property known as “birefringence” that’s shared by certain crystals, such as the ones that enable LCD screens. In 2020, Komatsu’s team reported finding a tiny rotation in the CMB’s polarization — about 0.35 degrees. A follow-up study published last year strengthened that earlier result.
***

"If the polarization study or another result related to the distribution of galaxies is confirmed, it would imply that the universe does not look the same in all directions to all observers. For Hill and many others, both results are tantalizing but not yet definitive. Follow-up studies are underway to investigate these hints and rule out potential confounding effects. Some have even proposed a dedicated “backlight astronomy” spacecraft that would further inspect the various shadows.
"
Comment: the CMB is a treasure which is still spilling its treasure.

2125 views

Smashing neutron stars:

https://www.scientificamerican.com/video/all-the-gold-in-the-universe-was-likely-create...

"Scientists have been combing the galaxy to figure out where these so-called “heavy elements” come from.

***

"For decades scientists theorized where these “heavy metals” came from and how they arrived on Earth. The leading idea was an extremely violent cosmic event—a collision between two neutron stars.

"Until recently this was just a theory—but that changed a few years ago, when scientists detected gravitational waves from such a crash—and saw light at the same time.

"This light held the chemical signatures of these heavy elements—offering the first evidence supporting the theory of where they came from. It also helped scientists fill in some of the details of how this process might work.

"Neutron stars are the densest things in the universe except for black holes. They are born when heavy stars die and their cores collapse. The incredible gravitational pressure squishes the atoms together, protons and electrons smush, all leaving a star almost entirely made of neutrons.

"In the rare case when two neutron stars slam together—the explosion creates mind-blowing temperatures and pressures.

"It also pumps out a lot of free neutrons—up to a gram of neutrons spills into every cubic centimeter of space.

"These rare conditions ignite what’s called the rapid neutron-capture process, otherwise known as “R-process” for short.

"It all starts with a seed nucleus, such as iron. The iron nucleus starts out with 26 protons and around 30 neutrons.

"But during the R-process, it will quickly capture many more neutrons in a matter of milliseconds. The new nucleus is highly unstable because of its lopsided quantity of neutrons, so some of the neutrons will decay into protons.

"The result of this extremely fast, complex process is a new form of matter."

Comment: bit by bit the universe is revealing its secrets.

3291 views

Many differences:

https://bigthink.com/starts-with-a-bang/sun-typical-star/?utm_campaign=weeklynewsletter...

"Stars come with a variety of properties: mass, color, temperature, ionization, metallicity, age, etc.

***

Most stars that exist today formed long ago: ~11 billion years in the past.

"Our Sun, born 4.6 billion years ago, is younger than 85% of all stars.

"Since time immemorial, we’ve wondered, “Is the Sun just a typical star?”

"Our Sun, a G-class star, is more massive than 95% of stars.

"Most stars are lower than ours in metallicity: the fraction of heavy elements present.

"Our Sun has greater enrichment than ~93% of all stars.

"Only half of all stars are “singlets” like our Sun; the other half exist within multi-star systems.

"We’re not typically luminous, either.

"The overall luminosity-to-mass ratio of stars is three times our own.

"Normal, apparently, encompasses an enormous range.

Comment: the age and properties of our sun offer more fine-tuning reasons for the Earth to allow life to appear. The sun and Earth are not near the averages for all other star system. It is obvious we are special

3208 views

Giant spirals galaxies appeared early after the Big Bang:

https://www.universetoday.com/159515/new-jwst-image-shows-that-grand-spiral-galaxies-ha...

For the first time this week, photos from the James Webb Space Telescope (JWST) revealed that stellar bars were present in some galaxies as far back as 11 billion years ago. Stellar bars are a defining feature of about two-thirds of all spiral galaxies in the Universe, including our own Milky Way. The discovery has implications for astronomers’ understanding of galactic evolution, indicating that bars form very quickly and may persist for much of a galaxy’s lifespan, influencing its shape and structure.

Stellar bars are regions of intense star formations that radiate out from a galaxy’s core. Through the motion of inner orbiting stars, dust, and gas clouds, they build up as a wave of dense material that perpetuates itself and spreads slowly outward while pulling raw material inwards. These regions become stellar nurseries that churn out new stars at a rapid pace.

The new JWST images, presented by The University of Texas at Austin on January 5th, show six barred spiral galaxies over 8.4 million years old, two of which are older than 11 billion years (the oldest galaxy ever seen is around 13.4 billion years old).

***

JWST has an advantage over Hubble in observing extremely old and distant galaxies, partly because its larger mirror can collect more light from distant, dim objects. But it also has an advantage due to its use of infrared rather than optical wavelengths. Light from older and more distant objects is ‘red-shifted’ along the electromagnetic spectrum, meaning that JWST’s detectors can pick them up better than Hubble can.

“Bars solve the supply chain problem in galaxies,” Jogee says. “Just like we need to bring raw material from the harbor to inland factories that make new products, a bar powerfully transports gas into the central region where the gas is rapidly converted into new stars at a rate typically 10 to 100 times faster than in the rest of the galaxy…This discovery of early bars means galaxy evolution models now have a new pathway via bars to accelerate the production of new stars at early epochs.”

Comment: this shows how the universe evolved in early time after the Big Bang. Be sure to go to the site to see the images.

3256 views

Unusual compared to other similar galaxies:

https://www.sciencealert.com/astronomers-just-realized-the-milky-way-is-too-big-for-its...

"...astronomers have just identified a quirk never before seen in any galaxy studied to date: the Milky Way is too big for its surroundings.

"Specifically, it appears to be too large for the neighborhood it sits within known as the Local Sheet. This flattened arrangement of galaxies share similar velocities, bounded by relatively empty space called voids on either side.

"Our Local Sheet, as an example of a 'cosmological wall', separates the Local Void in one direction from the Southern Void in the other.

"The relationship between the galaxies in the Local Sheet seems to exert a strong influence over their behavior; for example, their similar velocities relative to the expansion of the Universe. Outside of the cosmological wall environment, these velocities would have a much wider range.

"To determine the effect the environment has on the galaxies around us, a team of astronomers led by Miguel Aragón of the National Autonomous University of Mexico conducted an analysis using simulations from a project called IllustrisTNG, which models the physical Universe.

***

"...when they simulated a volume of space about a billion light-years across containing millions of galaxies, a different picture emerged: just a scant handful of galaxies as massive as the Milky Way could be located within a cosmological wall structure.

""The Milky Way doesn't have a particularly special mass, or type. There are lots of spiral galaxies that look roughly like it," says astronomer Joe Silk of Sorbonne University's Institut d'Astrophysique de Paris in France.

"'But it is rare if you take into account its surroundings. If you could see the nearest dozen or so large galaxies easily in the sky, you would see that they all nearly lie on a ring, embedded in the Local Sheet. That's a little bit special in itself. What we newly found is that other walls of galaxies in the Universe like the Local Sheet very seldom seem to have a galaxy inside them that's as massive as the Milky Way."

"The team's analysis didn't take into account Andromeda, the Milky Way's largest galactic neighbor. Also a feature of the Local Sheet – and therefore a part of the same cosmological wall – it's a galaxy of a similar size to the Milky Way. Since having two heavyweights in a cosmological wall would be even rarer still, their conclusions still apply.

"However, the research does highlight that we might need to consider our local environment when studying the Milky Way, rather than assuming that our home hangs out in an average way in an average spot in the Universe.

"Because the team's simulations only considered the Milky Way's context within a cosmological wall, perhaps future work could account for more galaxies within the Local Group. The researchers also note that the environmental context could help explain some previously unexplained phenomena, such as the unusual arrangement of satellite galaxies around Andromeda, and the peculiar lack of them around the Milky Way.

""You do have to be careful … choosing properties that qualify as 'special'," says astronomer Mark Neyrinck of the Basque Foundation for Science in Spain.

""If we added a ridiculously restrictive condition on a galaxy, such as that it must contain the paper we wrote about this, we would certainly be the only galaxy in the observable Universe like that. But we think this 'too big for its wall' property is physically meaningful and observationally relevant enough to call out as really being special."

Comment: as usual, everything related to us is unusual. I appreciate the writers caution in looking for special attributes. But we find them every time we look, which allows a believer to see God's handiwork.

3198 views

The local sheet makes us special:

https://www.universetoday.com/159754/according-to-simulations-the-milky-way-is-one-in-a...

"...the Illustris TNG simulation shows that the Milky Way is special.

"Illustris TNG is an ongoing series of large-scale simulations. The goal is to understand the mechanisms behind galaxy formation and evolution. The effort is a “series of large, cosmological magnetohydrodynamical simulations,” according to the Illustris TNG website. So far, the project has produced three primary runs, each one larger and higher resolution than the previous one: TNG 50, TNG 100, and TNG 300. Each run also focuses on various aspects of galaxy formation. TNG 300 is the largest, simulating a region of almost 300 million megaparsecs, over a billion light-years across, and containing millions of galaxies.

***

"New research based on Illustris TNG shows that the Milky Way is special. But it’s not special purely for its intrinsic qualities. It’s special in relation to its surroundings.

"The findings are in a new paper based on Illustris TNG 300 published in the Monthly Notices of the Royal Astronomical Society. The title is “The unusual Milky Way-local sheet system: implications for spin strength and alignment.” The lead researcher is Miguel Aragón, a computational cosmologist and assistant professor at the National Astronomical Observatory, Universidad Nacional Autonoma de Mexico.

***
"Cosmological walls are made up of galaxies. They’re a subtype of filaments, but they’re flattened and have voids on either side. The voids seem to squash the walls into their flattened shape. The cosmological wall nearest the Milky Way is called the Local Wall or Local Sheet.

"The Local Sheet influences how the Milky Way and other nearby galaxies rotate on their axes. The Milky Way takes about 250,000,000 years to rotate, and the study shows that the rotation is more organized than if the galaxy wasn’t near the Local Sheet.

"The study also shows that the Milky Way is special. While typical galaxies tend to be much smaller in relation to walls, the Milky Way is surprisingly massive in relation to the Local Wall. According to the research, this is a rare cosmic occurrence.

***

"Specifically, the Local Sheet affects the spin of the Milky Way. “… there are particularly strong alignments between the sheet and galaxy spins,” they explain, adding that in the simulation, the galaxies near walls have low spin parameters.

"This all affects how galaxies grow and merge over time, they think. It leads to lower-mass galaxies in these types of cosmic neighbourhoods. That’s why the Milky Way, with its high mass, is so unusual and why the simulation found only one like it in up to 200 cubic megaparsecs of space.

***

“'The Milky Way doesn’t have a particularly special mass or type. There are lots of spiral galaxies that look roughly like it,” Joe Silk, another of the researchers, said. “But it is rare if you take into account its surroundings. If you could see the nearest dozen or so large galaxies easily in the sky, you would see that they all nearly lie on a ring embedded in the Local Sheet. That’s a little bit special in itself. What we newly found is that other walls of galaxies in the Universe like the Local Sheet very seldom seem to have a galaxy inside them that’s as massive as the Milky Way.”

***

“"You do have to be careful, though, choosing properties that qualify as ‘special,’” Dr. Mark Neyrinck, another member of the team, said. “If we added a ridiculously restrictive condition on a galaxy, such as that it must contain the paper we wrote about this, we would certainly be the only galaxy in the observable Universe like that. But we think this ‘too big for its wall’ property is physically meaningful and observationally relevant enough to call out as really being special.'”

Comment: life appeared after many astronomical contingencies which created our special neighborhood and the Milky Way specialness. Luck or design? Take your preference, you know
mine.

3185 views

New Webb telescope sightings and theories:

https://www.quantamagazine.org/astronomers-say-they-have-spotted-the-universes-first-st...

"Agroup of astronomers poring over data from the James Webb Space Telescope (JWST) has glimpsed light from a rare isotope of helium in a distant galaxy, which could indicate the presence of the universe’s very first generation of stars.

"These long-sought, inaptly named “Population III” stars would have been ginormous balls of hydrogen and helium sculpted from the universe’s primordial gas. Theorists started imagining these first fireballs in the 1970s, hypothesizing that, after short lifetimes, they exploded as supernovas, forging heavier elements and spewing them into the cosmos. That star stuff later gave rise to Population II stars more abundant in heavy elements, then even richer Population I stars like our sun, as well as planets, asteroids, comets and eventually life itself.

***

"About 400,000 years after the Big Bang, electrons, protons and neutrons settled down enough to combine into hydrogen and helium atoms. As the temperature kept dropping, dark matter gradually clumped up, pulling the atoms with it. Inside the clumps, hydrogen and helium were squashed by gravity, condensing into enormous balls of gas until, once the balls were dense enough, nuclear fusion suddenly ignited in their centers. The first stars were born.

"The German astronomer Walter Baade categorized the stars in our galaxy into types I and II in 1944. The former includes our sun and other metal-rich stars; the latter contains older stars made of lighter elements. The idea of Population III stars entered the literature decades later. In a 1984 paper that raised their profile, the British astrophysicist Bernard Carr described the vital role this original breed of star may have played in the early universe. “Their heat or explosions could have reionized the universe,” Carr and his colleagues wrote, “… and their heavy-element yield could have produced a burst of pregalactic enrichment,” giving rise to later stars richer in heavier elements.

"Carr and his co-authors estimated that the stars could have grown to immense sizes, measuring anywhere between a few hundred and 100,000 times more massive than our sun, because of the large volume of hydrogen and helium gas available in the early universe.

***

"Windhorst leads a JWST program that is attempting the technique. “I’m pretty confident that in a year or two we will have seen some,” he said. “We already have some candidates.” Similarly, Eros Vanzella, an astronomer at the National Institute for Astrophysics in Italy, is leading a program that’s studying a clump of 10 or 20 candidate Population III stars using gravitational lensing. “We are just playing with the data now,” he said.

"And there remains the tantalizing possibility that some of the unexpectedly bright galaxies already seen by JWST in the early universe could owe their brightness to massive Population III stars. “These are exactly the epochs where we expect the first stars are forming,” Vanzella said. “I hope … that in the next weeks or months, the first stars will be detected.”

"Those at the heavier end of the range, so-called supermassive stars, would have been relatively cool, red and bloated, with sizes that could encompass almost our entire solar system. Denser, more modestly sized variants of Population III stars would have shone blue hot, with surface temperatures of some 50,000 degrees Celsius, compared to just 5,500 degrees for our sun.

***

"Their immense proportions meant the stars were short-lived, lasting a few million years at most. (More massive stars burn through their available fuel more quickly.) As such, Population III stars wouldn’t have lasted long in the history of the universe — perhaps a few hundred million years as the last pockets of primordial gas dissipated.

"There are many uncertainties. How massive did these stars really become? How late into the universe did they exist? And how abundant were they in the early universe? “They’re completely different stars to the stars in our own galaxy,” Bowler said. “They’re just such interesting objects.”

***

"...in 1999, astronomers at the University of Colorado, Boulder predicted that the stars should produce a telltale signature: a specific frequency of light from helium-2."

***

"Windhorst leads a JWST program that is attempting the technique. “I’m pretty confident that in a year or two we will have seen some,” he said. “We already have some candidates.” Similarly, Eros Vanzella, an astronomer at the National Institute for Astrophysics in Italy, is leading a program that’s studying a clump of 10 or 20 candidate Population III stars using gravitational lensing. “We are just playing with the data now,” he said.

"And there remains the tantalizing possibility that some of the unexpectedly bright galaxies already seen by JWST in the early universe could owe their brightness to massive Population III stars. “These are exactly the epochs where we expect the first stars are forming,” Vanzella said. “I hope … that in the next weeks or months, the first stars will be detected.'”

Comment: in a matter time those theoretical stars will be seen

3176 views

Another view:

https://www.nationalgeographic.com/magazine/article/nasa-jwst-most-ancient-galaxies-in-...

“'JWST has absolutely changed our definition of high-z,” writes Guido Roberts-Borsani of the University of California, Los Angeles, in an email. In 2015, he says, the most distant galaxies known had redshift values of 8 or 9. But then the Hubble Space Telescope spotted a galaxy later named GN-z11 around redshift 11 and pushed the first galaxies even further back in time.

“'Now JWST has eclipsed that,” Roberts-Borsani says, and the redshift frontier has been moved to values of 12 or 13, equating to about 13.3 or 13.4 billion years ago.

***

“'We’ve shifted into a completely new regime—this is the first time we’ve got confirmation of anything further away than Hubble could see, and this is just the beginning,” Curtis-Lake, a member of the JWST Advanced Deep Extragalactic Survey (JADES) collaboration, told National Geographic.

***

"Curtis-Lake, Robertson, and their colleagues confirmed the distances to four galaxies that populated the primordial cosmos when it was only about 300 or 400 million years old. Two of them, though they are wicked far away, had also been spied by Hubble. The other two are farther away than anything Hubble could see, with redshifts of 12.6 and 13.2. These galaxies are largely made of lighter elements such as hydrogen and helium because they existed before large amounts of heavier elements had time to form.

“'They’re sort of like little baby toddlers in a universe that hasn’t really got going yet,” Curtis-Lake says.

***

"At first glance, it appears as though the early universe was more prodigious at cooking up stars and galaxies than scientists anticipated.

“'The galaxies we’re finding at those redshifts are more numerous than we expected based on previous observations, and they are also brighter than we expected at those redshifts,” Roberts-Borsani writes. “To fit this ‘new’ picture, galaxies had to start forming earlier and faster than previously thought.”

"Roberts-Borsani is a member of the GLASS-JWST collaboration, which is also searching for high-redshift galaxies and studying them to understand cosmic evolution. The GLASS collaboration studied a patch of sky that lies behind a massive cluster of galaxies, and the team has already uncovered a handful of apparently primordial galaxies—more than simulations had predicted. “Something’s a little bit weird over there,” Roberts-Borsani told astronomers in Baltimore.

"But, he says, there are ways to explain the apparent overabundance without breaking the currently established laws of the universe. Telescopes like JWST can only image small areas of the sky at one time, so by chance, teams could be studying portions of the sky that are unusually stuffed with galaxies. Another possibility is that these early galaxies are simply brighter than expected, perhaps because star formation worked differently than thought. A third explanation is that estimates based on Hubble observations are incomplete because of Hubble’s limited observing capabilities, and maybe, for still unexplained reasons, the early universe was more efficient at turning the lights on than anticipated."

Comment: time will answer the current issues. What appears to be true is the initial conditions baked into the origin of the universe dictated lots of galaxies. Looks like design to me.

3302 views

From an interview:

https://arxiv.org/pdf/2301.07198.pdf

"Georges Lemaˆıtre (1894-1966) was a Professor of Physics
at the Catholic University of Leuven and a Roman Catholic priest. He is widely known as being among the firsts to formulate a theory of the Big Bang. He has also independently attributed the observed recession of nearby galaxies to an expanding Universe. Georges Lemaˆıtre is undeniably one of the key physicist of the XXth century and an important figure of the history of astronomy (Lemaˆıtre 1927; Lemaˆıtre & Eddington 1931; Lemaˆıtre 1931). A video interview of Georges Lemaˆıtre talking about his work is a historical gem. As such, we aim to make this recording as accessible as possible for the astronomy community, and the general public at large.

***

"It is that Fred Hoyle, in presenting his Steady State theory, implies that the whole universe satisfies a group, a particular group, which satisfies space as a whole. Maybe it could be explained more clearly. It could be explained more clearly by saying this: a very long time ago, before the theory of the expansion of the universe (some 40 years ago), we expected the universe to be static. We expected that nothing would change. It was an a priori idea that applied to the whole universe...

***

"GLM: You remember, he said that when he started this theory, he thought he had to reject it. The expression he wrote down: ”well nothing much happens, nothing much happens” [...] because, he said, there should be creation. What does this mean... creation ? This word, creation, brings with it a whole philosophical or religious resonance that has nothing to do with the question. Behind this word, creation, what is there? There is simply that the apparition of hydrogen, as Hoyle supposes, is something quite fantastic and unexpected. That’s why he used the word creation. It is absolutely unexpected. And if I had to use another imagery to express the same thing, I would say that this hydrogen appears in a totally unexpected way like a ghost [dramatic emphasis on the word "ghost"].

***

"In fact, Hoyle recognizes that there are many theories that he calls ”Big Bang theory”, right. I don’t know to what extent the arrows he shoots against these theories are actually hitting the mark. But as far as the oldest of these theories is concerned, the one I proposed in 1931 under the name of the hypothesis of the primeval atom. I have the impression that his arrows do not reach me at all. I am even a little surprised that he doesn’t realize this,
because we have so often had the opportunity to talk, Hoyle and me, in the most friendly way. If you like, I have the impression that he was mostly concerned with what he imagined the theory to be rather than what it is. Especially the aspect of it that I have developed. So I think that this theory escapes.... ”And quite early on in the game, all the galaxies are supposed to have formed and then should therefore be..” and so on . This is not at all how I have ever considered the theory of the primeval atom. There is a beginning... we may touch on other aspects at some point... there is a beginning very different from the present state of the world, a beginning in multiplicity which can be described in that it can be described in the form of the disintegration of all existing matter into an atom. What will be the first result of this disintegration, as far as we can follow the theory, is in fact to have a universe, an expanding space filled by a plasma, by very energetic rays going in all directions.... Then by a process that we can vaguely imagine, unfortunately we cannot follow that in very many details, gases had to form locally; gas clouds moving with great speeds...

***

"JV: Monsignor, does the fact that the universe, according to your theory, has a beginning (at least one beginning)...does it have a religious meaning for you, a religious significance?

"GLM: Well, of course it must be explained... It is quite clear that in these interviews, the use of the word creation has provoked a rather particular turn in these interviews. Each one of them freely, and legitimately, exposed their views... These views were presented rather from the agnostic, materialist, or rather pantheist point of view. I don’t think there would be any interest... any advantage in me opposing these positions that everybody are aware
of... to make a confession of my religious convictions. It wouldn’t make much sense. The point is, to answer your question by dismissing precisely what many people expect, [the point] is that I am not defending the primeval natom for the sake of whatever religious ulterior motive. Ofn course, nobody knows exactly what one’s psychology is, really. But, not only consciously I don’t have this idea at all,n I think that the impact of this theory in the philosophical, philosophicoreligious problem is essentially different. It is a point obviously a little delicate. I am a bit afraid to elaborate on it in a few words now. I elaborated on it extensively in a conference that I gave a few months ago in Namur and that was on your airwaves, but on the French airwaves|| and it is precisely that if my theory is correct, it makes the philosophical problem of creation disappear, in a way."

Comment: offered as an historical, philosophical background perspective from the past.

3023 views

From Jan31st miscellany: "dhw: [/b]Billions and billions of stars that come and go, and they all look like design to you. So what do you reckon: another 99% failure rate?"

They are not failures but contribute to the next generation of stars:

https://mail.google.com/mail/u/0/#inbox/FMfcgzGrcPQQfdcQQhzMnfbGkCwDTwxC

"The Sun is a third-generation star, containing the heavier elements from previous generations of stars that lived and died. But first-generation stars must have formed from the primordial hydrogen and helium left over from the Big Bang. Astronomers haven't been able to detect them yet, but a new simulation predicts that they might be extremely massive, with some reaching 100,000 times the mass of the Sun." (my bold)

https://www.universetoday.com/159800/the-first-stars-may-have-weighed-more-than-100000-...

"The universe was simply different when it was younger. Recently astronomers have discovered that complex physics in the young cosmos may have led to the development of supermassive stars, each one weighing up to 100,000 times the mass of the Sun.

"We currently have no observations of the formation of the first stars in the universe, which is thought to have taken place when our cosmos was only a few hundred million years old. To understand this important epoch, astronomers turn to sophisticated computer simulations to test out models of how the first stars formed.

"Over the years astronomers have wrestled with the key question of what is the typical size of the first stars. Some early estimates predicted that the first stars could be hundreds of times more massive than the Sun, while later simulation suggested that they would be more normally sized.

"Recently a team of researchers have put together a new round of simulations and come to a very surprising conclusion. Their simulations specifically looked at a phenomenon known as cold accretion. To build large stars you have to pull a lot of material into a very small volume very quickly. And you have to do it without raising the temperature of the material, because warmer material will prevent itself from collapsing. So you need some method of removing heat from material as it collapses very quickly.

"Earlier simulations had found the appearance of dense pockets within early galaxies that cool off rapidly from emitting radiation, but did not have the resolution needed to follow their further evolution. The new research takes it a step further by examining how the cold dense pockets that initially form in the early universe behave.

"This simulations revealed that large flows of cold, dense matter can strike an accretion disk at the center of giant clumps of matter. When that happens a shockwave forms. That shockwave rapidly destabilizes the gas and triggers the instant collapse of large pockets of matter.

"Those large pockets can be tens of thousands times more massive than the Sun, and in some cases even 100,000 times more massive than the Sun. With nothing to stop their collapse, they immediately form gigantic stars, known as supermassive stars.

"The astronomers do not yet know if supermassive stars formed in the early universe. They hope that future observations with the James Webb Space Telescope will reveal clues as to the formation of the first stars and galaxies and determine if these monsters appeared in the infant universe."

Comment: dhw raises negative opinions, as in the quote above, while admitting his science education is small. My role is to look for answers. The answer here is obvious. Stars go through generations of types as the early universe evolves into the present form. Our sun is third generation from about five billion years ago. It is a 'metallic' star containing the important metals we use today on Earth. We can say a very special Earth comes from a very special sun. I'll now repeat. Looks designed to me.

2977 views

From Jan 31st miscellany: "dhw: Billions and billions of stars that come and go, and they all look like design to you. So what do you reckon: another 99% failure rate?"

DAVID: They are not failures but contribute to the next generation of stars:

https://mail.google.com/mail/u/0/#inbox/FMfcgzGrcPQQfdcQQhzMnfbGkCwDTwxC

QUOTE: "The Sun is a third-generation star, containing the heavier elements from previous generations of stars that lived and died. But first-generation stars must have formed from the primordial hydrogen and helium left over from the Big Bang. Astronomers haven't been able to detect them yet, but a new simulation predicts that they might be extremely massive, with some reaching 100,000 times the mass of the Sun." (David’s bold)

DAVID: dhw raises negative opinions, as in the quote above, while admitting his science education is small. My role is to look for answers. The answer here is obvious. Stars go through generations of types as the early universe evolves into the present form. Our sun is third generation from about five billion years ago. It is a 'metallic' star containing the important metals we use today on Earth. We can say a very special Earth comes from a very special sun. I'll now repeat. Looks designed to me.

You are lumbering yourself with exactly the same problem as you have with the evolution of life. I have never questioned the fact that we and the rest of the universe have evolved. If God exists, he is responsible for the evolution of us and the rest of the universe. However, you now theorize that your God’s evolution of life entailed designing 99% of life forms that you regard as mistakes/failed experiments/a mess because they did not lead to us and our food. Here you theorize that your God’s evolution of the universe entailed designing billions of trillions of stars in order to produce one star and one planet in one galaxy. I can’t see any reason why an all-powerful God needed to do this, so I ask you: why do you believe that it was necessary for your God to design all the billions of trillions of stars, including all those which have disappeared, for the sole purpose of producing our special sun and our special Earth? Is this another example of what you believe to be your God’s 99% failure rate and 1% success?

3651 views

From Jan 31st miscellany: "dhw: Billions and billions of stars that come and go, and they all look like design to you. So what do you reckon: another 99% failure rate?"

DAVID: They are not failures but contribute to the next generation of stars:

https://mail.google.com/mail/u/0/#inbox/FMfcgzGrcPQQfdcQQhzMnfbGkCwDTwxC

QUOTE: "The Sun is a third-generation star, containing the heavier elements from previous generations of stars that lived and died. But first-generation stars must have formed from the primordial hydrogen and helium left over from the Big Bang. Astronomers haven't been able to detect them yet, but a new simulation predicts that they might be extremely massive, with some reaching 100,000 times the mass of the Sun." (David’s bold)

DAVID: dhw raises negative opinions, as in the quote above, while admitting his science education is small. My role is to look for answers. The answer here is obvious. Stars go through generations of types as the early universe evolves into the present form. Our sun is third generation from about five billion years ago. It is a 'metallic' star containing the important metals we use today on Earth. We can say a very special Earth comes from a very special sun. I'll now repeat. Looks designed to me.

dhw: You are lumbering yourself with exactly the same problem as you have with the evolution of life. I have never questioned the fact that we and the rest of the universe have evolved. If God exists, he is responsible for the evolution of us and the rest of the universe. However, you now theorize that your God’s evolution of life entailed designing 99% of life forms that you regard as mistakes/failed experiments/a mess because they did not lead to us and our food. Here you theorize that your God’s evolution of the universe entailed designing billions of trillions of stars in order to produce one star and one planet in one galaxy. I can’t see any reason why an all-powerful God needed to do this, so I ask you: why do you believe that it was necessary for your God to design all the billions of trillions of stars, including all those which have disappeared, for the sole purpose of producing our special sun and our special Earth? Is this another example of what you believe to be your God’s 99% failure rate and 1% success?

Exactly. Why do you keep ignoring my major point that God always evolves every aspect of His intentions. Our Milky Way and our Earth were carefully evolved to take advantage of all 92 initial elements we have that were also evolved in stars that have died. Evolution has successes and failures as natural components of such a system. Evolution always is a prolonged process of 99% failure and one percent success, It continues on the successes. I am one of God's successes and so are you. You have again twisted this reality into an attack on my reasoning capacity as if I don't realize how wrong I am. Remember you are balancing on your picket fence never allowing coming down on either side.

3045 views

dhw appears to have little recognition God evolves everything; here is how the universe it was done:

https://bigthink.com/starts-with-a-bang/quantum-reason-neutral-atoms/?utm_campaign=swab...

"In order for you to exist, a lot of things had to happen beforehand. Planet Earth needed to come into existence, complete with the organic ingredients from which life could arise. In order to have those ingredients, we need for many previous generations of stars to have lived-and-died, recycling the elements formed within them back into the interstellar medium. For those stars to live, large quantities of neutral, molecular gas had to collect in one place, collapsing under its own gravity to fragment and form stars in the first place. But in order to make those stars — even the very first stars — we first need the Universe to create stable, neutral atoms.

"In a Universe that begins with a hot Big Bang, this isn’t necessarily so easy! A few minutes after the hot Big Bang, our Universe was filled with protons and a small but important population of more complex light atomic nuclei, an equal number of electrons to the total number of protons, a large number of neutrinos that don’t interact with any of them, and about 1.4 billion photons for every proton-or-neutron present. (There’s also dark matter and dark energy, but like neutrinos, they’re not important to this part of the story.)

"So how long does it take these protons and other nuclei to combine with electrons, stably forming neutral atoms? A whopping 380,000 years. But that’s only because of a very special quantum reason. Without it, things would have taken much longer. Here’s the science behind it.

"In the early stages of the Universe, things were very dense, very uniform, and very hot. That last part — very hot — has two important consequences that we cannot ignore.

"Particles with non-zero rest masses move very quickly, even close to the speed of light, and when they collide with one another, those are high-energy collisions, capable of breaking apart anything that isn’t bound together tightly enough.

"Particles that are massless, like photons, although they always move at the speed of light, possess very large amounts of kinetic energy as well, which means they have very short wavelengths and also initiate high-energy collisions that are capable of breaking apart any bound structures they run into.

***

"In the hot, early Universe, once atomic nuclei have been created, making a neutral atom is easy, but destroying that neutral atom and converting it back into a bare nucleus and free electrons is both inevitable and fast. Neutral atoms are formed, but they aren’t stable in this environment.

***

"As the Universe continues to age, it also expands, which stretches the wavelength of every photon traveling through it. If we want to ask how old the Universe is when only 1-in-1.4 billion photons reaches or exceeds 13.6 eV in energy, that threshold is crossed when the Universe is only a little more than 100,000 years old. But still, when we examine the Universe at that time, the neutral atoms that are formed aren’t stable, but rather get blasted apart again in short order.

***

"...even once the Universe cools sufficiently so that the background photons left over from the Big Bang won’t ionize a hydrogen atom, the newly-formed hydrogen atoms are vulnerable to photons produced by the act of other hydrogen atoms becoming neutral. The key isn’t just to form neutral hydrogen; the key is to form neutral hydrogen that’s stable: that won’t be reionized in short order from the surrounding radiation, even radiation that comes from the production of other neutral hydrogen atoms.

***

"The Universe, as observed by many ground-based instruments, telescopes, receivers, and space-based satellites, became neutral back when the Universe was only ~380,000 years old and was more like ~3000 K in temperature. It’s a gradual process, taking more than 100,000 years to complete, but it happens much more rapidly than simply folding in cosmic expansion and atomic physics would lead you to believe.

***

"If there were no atoms at all, it would take over a billion years to have the Universe become transparent to light. If it weren’t for the quantum mechanical possibility of having a two-photon transition, it would have taken nearly a million years for the Universe to become transparent to form neutral atoms and become transparent to light. But with the actual laws of quantum mechanics and a Universe that expanded and cooled since the hot Big Bang, it’s only a mere 380,000 years until practically all of the atoms within it are neutral and stable, and the (now-infrared) light present within it can simply stream freely through space. It sets the stage for the formation of the first stars, and once gravitation, nuclear fusion, and time all do their things, planets, life, and complex organisms can arise, reconstructing what happened all those billions of years before!"

Comment: ALL OF IT IS EVOLUTION!!! GOD EVOLVES EVERYTHING. It is ALWAYS His pattern of creation. dhw take notice!! Complex quantum rules are skipped so dhw is comfortble.

2753 views

dhw appears to have little recognition God evolves everything; here is how the universe it was done:

https://bigthink.com/starts-with-a-bang/quantum-reason-neutral-atoms/?utm_campaign=swab...

DAVID: ALL OF IT IS EVOLUTION!!! GOD EVOLVES EVERYTHING. It is ALWAYS His pattern of creation. dhw take notice!! Complex quantum rules are skipped so dhw is comfortable.

I have replied to this on the "David's theory" thread, since it is yet another complete distortion of my arguments against that theory.

2748 views

dhw appears to have little recognition God evolves everything; here is how the universe it was done:

https://bigthink.com/starts-with-a-bang/quantum-reason-neutral-atoms/?utm_campaign=swab...

DAVID: ALL OF IT IS EVOLUTION!!! GOD EVOLVES EVERYTHING. It is ALWAYS His pattern of creation. dhw take notice!! Complex quantum rules are skipped so dhw is comfortable.

dhw: I have replied to this on the "David's theory" thread, since it is yet another complete distortion of my arguments against that theory.

I'll hop over

2739 views

We are moving from one region to another in the universe:

https://www.newscientist.com/article/2359129-were-hurtling-into-a-new-region-of-interst...

"Over the past decade or so, researchers like Bania have been showing that interstellar space is deeply fascinating. This so-called nothingness is brimming with exotic molecules, pulsating with radio waves and divided into gigantic bubbles, each with their own character. Now, as we are beginning to map out our place within the void more keenly, we are coming to see that this variety matters immensely – and that as the solar system heads towards a new region of interstellar space, there could be important ramifications for life on Earth.

"We are used to living in a thick soup of atmosphere. In a cubic centimetre of air, a volume the size of a six-sided dice, there are trillions of atoms. Gas, dust, water vapour, viruses, pollen and more all waft around. Just beyond our atmosphere, however, in interplanetary space, the conditions are close to a perfect vacuum. “Space is huge, and it’s mostly empty,” says Seth Redfield at Wesleyan University in Connecticut. Out there, the same volume contains, on average, just five atoms.

"This matter mostly consists of charged particles streaming out from the sun as the solar wind. We have known for decades about this flow of material and how it creates a protective zone around the solar system called the heliosphere. It cocoons us from high‑energy cosmic rays shooting at us from deep space – and a good thing too, because those rays can damage the cells and DNA in living things. Radiation levels are eight to 10 times higher outside this zone. “Without our heliosphere, would life even exist?” asks Jamie Rankin at Princeton University.

***

"The discovery kick-started a new field, the study of molecules drifting in the interstellar medium. Bania is one of those who led the charge. “The big breakthrough in my lifetime was the whole discovery of molecules in interstellar space,” he says. As of 2022, some 256 types had been found, mostly identified from the way they absorb specific wavelengths of passing radio waves. “We found this rich molecular chemistry in space,” says Bania.

***

"On a grander scale, our 10-light-year-wide Local Interstellar Cloud resides in a much larger, irregularly shaped structure called the Local Bubble, which is 1000 light years across. This is a giant shell of expanding gas formed by more than a dozen stars exploding as supernovae, with a density around a tenth that of the space outside the Local Bubble. Recent estimates have suggested that our solar system entered this bubble about 5 million years ago, and we are now roughly at its centre.

"In another 8 million years, it is predicted we will reach its edge. In 2022, Catherine Zucker at the Space Telescope Science Institute in Maryland and her colleagues used the European Space Agency’s Gaia telescope to track the motions and positions of stars in our vicinity. This showed that the centre of the Local Bubble is relatively empty, but that the edges have a much higher density of material. “We’re accidentally in a great position,” says Zucker. (my bold)

"Yet that could change as we near the edge. Ongoing work by Opher suggests the higher pressure we would experience as we near the edge of the Local Bubble would shrink the heliopause to the wrong side of Earth’s orbit, exposing us to far more cosmic rays. Earth would be “in interstellar space”, says Opher. It is reasonably well known that the sun will get much hotter over the next billion years, hot enough to boil Earth’s oceans away. But our traverse of interstellar space could have its own serious consequences for life on Earth far sooner. “Where we were in the past and where we are going to be in the future is critical,” says Opher. “I think it will have a direct effect on habitability.'” (my bold)

Comment: the universe is way more complex than we knew. Note my bolds. Accidental safe zone or God's designed protection?

2885 views

Bases on observed systems types ours is rarest:

https://www.sciencedaily.com/releases/2023/02/230214154018.htm

"Venus, Earth or Mars, orbit relatively close to our star. The large gas and ice giants, such as Jupiter, Saturn or Neptune, on the other hand, move in wide orbits around the sun. In two studies published in the scientific journal Astronomy & Astrophysics, researchers from the Universities of Bern and Geneva and the National Centre of Competence in Research (NCCR) PlanetS show that our planetary system is quite unique in this respect.

***

"...the researcher developed a framework to determine the differences and similarities between planets of the same systems. And in doing so, he discovered that there are not two, but four such system architectures.

"'We call these four classes 'similar', 'ordered', 'anti-ordered' and 'mixed'," says Mishra. Planetary systems in which the masses of neighbouring planets are similar to each other, have similar architecture. Ordered planetary systems are those, in which the mass of the planets tends to increase with distance from the star – just as in our solar system. If, on the other hand, the mass of the planets roughly decreases with distance from the star, researchers speak of an anti-ordered architecture of the system. And mixed architectures occur, when the planetary masses in a system vary greatly from planet to planet.

"'This framework can also be applied to any other measurements, such as radius, density or water fractions," says study co-author Yann Alibert, Professor of Planetary Science at the University of Bern and the NCCR PlanetS. "Now, for the first time, we have a tool to study planetary systems as a whole and compare them with other systems."

***

"'Our results show that 'similar' planetary systems are the most common type of architecture. About eight out of ten planetary systems around stars visible in the night sky have a 'similar' architecture," says Mishra. "This also explains why evidence of this architecture was found in the first few months of the Kepler mission." What surprised the team was that the "ordered" architecture – the one that also includes the solar system – seems to be the rarest class. (my bold)

"According to Mishra, there are indications that both the mass of the gas and dust disk from which the planets emerge, as well as the abundance of heavy elements in the respective star play a role. "From rather small, low-mass disks and stars with few heavy elements, 'similar' planetary systems emerge. Large, massive disks with many heavy elements in the star give rise to more ordered and anti-ordered systems. Mixed systems emerge from medium-sized disks. Dynamic interactions between planets – such as collisions or ejections – influence the final architecture," Mishra explains.

"'A remarkable aspect of these results is that it links the initial conditions of planetary and stellar formation to a measurable property: the system architecture. Billions of years of evolution lie in between them. For the first time, we have succeeded in bridging this huge temporal gap and making testable predictions. It will be exciting to see if they will hold up," Alibert concludes."

Comment: our solar system seems most unique so for. No surprise. Uniqueness protects us.

2682 views

Are there giant galaxies in our early past or not:

https://www.scientificamerican.com/article/jwst-discovers-enormous-distant-galaxies-tha...

JWST Discovers Enormous Distant Galaxies That Should Not Exist
JWST discovers giant, mature galaxies that seem to have filled the universe shortly after the Big Bang, and astronomers are puzzled

OR

https://www.scientificamerican.com/article/ancient-giant-galaxy-grew-fast-and-died-young1/

The newfound giant, known as XMM-2599, lies about 12 billion light-years from Earth, meaning that scientists are seeing the galaxy as it existed when the universe was quite young. (The Big Bang that created the universe occurred 13.82 billion years ago.)

“Even before the universe was 2 billion years old, XMM-2599 had already formed a mass of more than 300 billion suns, making it an ultramassive galaxy,” Benjamin Forrest, a postdoctoral researcher in the Department of Physics and Astronomy at the University of California Riverside (UCR), said in a statement.

***

“Even though such massive galaxies are incredibly rare at this epoch, the models do predict them,” study co-author Gillian Wilson, a physics and astronomy professor at UCR who heads the lab in which Forrest works, said in the same statement. (my bold)

Comment: I am aware of another study I've very recently read but can't seem to locate at the moment that validates the second article. My point: science reporting is not immune from sensationalizing. The science literature is enormous. Take care.

***

I should be more patient. Here is the suporting missing story:

https://www.sciencenews.org/article/giant-active-galaxies-early-universe-may-have-final...

Astronomers may finally have laid eyes on a population of enormous but elusive galaxies in the early universe.

These hefty, star-forming galaxies are shrouded in dust, which hid them from previous searches that used starlight. Now observations of radiation emitted by that interstellar dust have revealed dozens of massive, active galaxies from when the universe was younger than 2 billion years, researchers report online August 7 in Nature. These galaxies may be the long-sought precursors to heavyweight galaxies seen later in the universe’s history, as well as the most massive galaxies around today.

2562 views

On shock waves:

https://www.universetoday.com/160207/some-elements-arrived-on-earth-by-surfing-supernov...

"When stars die, they spread the elements they’ve created in their cores out to space. But, other objects and processes in space also create elements. Eventually, that “star stuff” scatters across the galaxy in giant debris clouds. Later on—sometimes millions of years later it settles onto planets. What’s the missing link between element creation and deposition on some distant world?

"That’s the question researchers asked themselves for years as they tried to figure out how heavy elements like manganese, iron, and plutonium showed up on Earth. It turns out they’re made in different processes, often in different parts of the Milky Way. Yet, they’ve been found layered together on Earth’s seabed. That implies they arrived about the same time, despite their different origins.

"Scientists from the University of Hertfordshire in the UK and the Konkoly Observatory, Research Centre for Astronomy and Earth Sciences in Hungary put together some theories and computer models to simulate how elements travel through space. The answer they came up with: the elements from faraway events are carried by supernova shock fronts just like surfers catching a wave.

"To understand how stuff from distant conflagrations ended up on Earth, it’s worth taking a quick look at those events. First, there are the Type II supernovae. They occur when a supermassive star dies. That’s one at least eight times the mass of the Sun. These stars fuse heavier and heavier elements (such as carbon) in their cores. When they get to creating iron, they don’t have enough energy to keep up the production line. The cores collapse and then everything expands outward very rapidly in a supernova explosion. That’s enough to send its heavy elements racing through space.

"Next, there are Type Ia supernovae. These happen in a binary pair of stars. Material from a main-sequence star accretes onto its partner, a white dwarf. When too much material accumulates, there’s an explosion. That results in the “nucleosynthesis” of heavier elements, including manganese.

"Another catastrophic event that likely creates heavy elements is the collision (or merger) of two neutron stars. As they spiral in toward each other and eventually smash up, they release a shower of neutrons. Those, in turn, bombard nearby atoms. This “r-process” event very quickly produces heavy elements such as plutonium.

***

"The modeling effort shows that isotopes can propagate through large areas of a galaxy via supernova shock waves. These fronts sweep up collections of elements from various sites."

Comment: strs make out necessary elements. Now we know how they get here. It fits my theory that God evolves aspects of reality. In this case He sets in motion processes He knows will work and lets it happen.

2548 views

It seems we are very active:

https://www.sciencenews.org/article/milky-way-star-formation-astronomy

"The Milky Way is churning out far more stars than previously thought, according to a new estimate of its star formation rate.

"Gamma rays from aluminum-26, a radioactive isotope that arises primarily from massive stars, reveal that the Milky Way converts four to eight solar masses of interstellar gas and dust into new stars each year, researchers report in work submitted to arXiv.org on January 24. That range is two to four times the conventional estimate and corresponds to an annual birthrate in our galaxy of about 10 to 20 stars, because most stars are less massive than the sun.

***

“'The star formation rate is very important to understand for galaxy evolution,” says Thomas Siegert, an astrophysicist at the University of Würzburg in Germany. The more stars a galaxy makes, the faster it enriches itself with oxygen, iron and the other elements that stars create. Those elements then alter star-making gas clouds and can change the relative number of large and small stars that the gas clouds form.

"Siegert and his colleagues studied the observed intensity and spatial distribution of emission from aluminum-26 in our galaxy. A massive star creates this isotope during both life and death. During its life, the star blows the aluminum into space via a strong wind. If the star explodes when it dies, the resulting supernova forges more. The isotope, with a half-life of 700,000 years, decays and gives off gamma rays.

"Like X-rays, and unlike visible light, gamma rays penetrate the dust that cloaks the youngest stars. “We’re looking through the entire galaxy,” Siegert says. “We’re not X-raying it; here we’re gamma-raying it.”

"The more stars our galaxy spawns, the more gamma rays emerge. The best match with the observations, the researchers find, is a star formation rate of four to eight solar masses a year. That is much higher than the standard estimate for the Milky Way of about two solar masses a year.

"The revised rate is very realistic, says Pavel Kroupa, an astronomer at the University of Bonn in Germany who was not involved in the work. “I’m very impressed by the detailed modeling of how they account for the star formation process,” he says. “It’s a very beautiful work. I can see some ways of improving it, but this is really a major step in the absolutely correct direction.'”

Comment: we live in a very lively galaxy, quite large, with so much gravitational attraction we are constantly gobbling up tiny satellite galaxies and so still growing by canabalism and new star manufacture.

2601 views

Has to be just the way it is:

https://www.sciencealert.com/astrophysicist-shows-how-one-small-change-to-our-solar-sys...

"As our catalog of planetary systems in the Milky Way grows, it becomes increasingly clear how very different our Solar System could have been.

"In fact, of the nearly 4,000 planetary systems identified to date, none of them reflect the order and arrangement of planets orbiting our own Sun. That could be because Solar System analogs are currently outside our detection ability. But from what we can detect out there, planetary systems seem to cover an extraordinary variety of arrangements.

"Now, astrophysicist Stephen Kane of the University of California, Riverside has shown that if we made just one change, the whole Solar System would go haywire.

"It's not even a big change, involving the addition of one more planet of a type seen frequently in other systems.

***

"What we do happen to have in the Solar System is a yawning great chasm between the rocky worlds and the gassy ones: a physical gap between the orbits of Mars and Jupiter, marked by an asteroid belt.

***

"Kane wanted to know what would happen to the Solar System if he filled both gaps in one fell swoop; he created simulations in which he plopped a planet with a range of masses between Mars and Jupiter right in that space, and watched the chaos ensue.

"And chaos there was indeed.

"'This fictional planet gives a nudge to Jupiter that is just enough to destabilize everything else," Kane says.

***

"Depending on the mass and location of this simulated world in the space between Mars and Jupiter, the chaos can result in the current planets being ejected clean out of the Solar System. Mars's average orbit lies 1.5 astronomical units from the Sun; Jupiter's at 5.2 astronomical units. A planet placed at 3 astronomical units can exist quite peacefully, but pretty much anywhere else results in an absolute planetary omnishambles.

"A planet at 3.1 to 4 astronomical units, Mercury's orbit becomes disrupted. At 2.0 to 2.7 astronomical units, Mars goes wobbly. Jupiter and Saturn only experience minor perturbations, but the angular momentum they impart to the outer Solar System worlds, Uranus and Neptune, causes the ice giants to destabilize too.

"At worst, Venus, Mercury, Earth, Mars, Uranus, and Neptune all get ejected from the Solar System. Smaller changes see Earth's orbit deviate wildly from its current course, rendering our home planet less habitable, if not completely inhospitable.c (my bold)

"Evidence already suggests that Jupiter plays a role in Earth's habitability, protecting us from asteroid bombardment. Kane's work suggests that it plays another role in stabilizing the Solar System: astronomers believe that Jupiter's gravitational influence prevents a planet from forming in the space the asteroid belt inhabits.

***

"Astronomers have thought for a while now that planetary systems with a Jupiter analog are the most likely to have the stability for life. Kane's simulations add more weight to the argument.

"They also suggest that the Solar System's architecture could be quite a delicate balance that is difficult to maintain.

"'Our Solar System is more finely tuned than I appreciated before," Kane says. "It all works like intricate clock gears. Throw more gears into the mix and it all breaks.'"

Comment: Another aspect of fine tuning which adds to the significance of that theory. The gravitational influences are adjusted just right. Note the bold. The whole issue is our privileged planet's habitability. Not by chance, but by design. Even those pesky asteroids are required.

2211 views

Much more than gravitational waves:

https://www.livescience.com/galaxy-size-shock-waves-found-rattling-the-cosmic-web-the-l...

"Astronomers have detected enormous shockwaves rattling the cosmic web that connects all galaxies in the universe, offering vital clues on how the largest structures in space were shaped.

"For the first time, astronomers have spotted enormous, galaxy-scale shock waves rattling the "cosmic web" that connects nearly all known galaxies. These cosmic waves could reveal clues about how the largest objects in the universe were sculpted.

"The discovery was made by stitching and stacking thousands of radio telescope images together, which revealed the soft "radio glow" produced by shock waves from colliding matter in our universe's biggest structures.

"The cosmic web is a gigantic network of crisscrossing celestial superhighways paved with hydrogen gas and dark matter. Galaxies tend to form where multiple strands of the web intersect, often in clusters numbering in the hundreds of thousands. Now a new study, published Feb. 15 in the journal Science(opens in new tab), could provide vital clues into the nature of the mysterious magnetic fields that stretch beside these tendrils.

***

"'Magnetic fields pervade the universe — from planets and stars to the largest spaces in-between galaxies," lead author Tessa Vernstrom, an astronomer at the International Centre for Radio Astronomy Research in Crawley, Australia, said in a statement. "However, many aspects of cosmic magnetism are not yet fully understood, especially at the scales seen in the cosmic web."

"Taking shape in the chaotic aftermath of the Big Bang, the cosmic web's tendrils formed as clumps of matter from the roiling particle-antiparticle broth of the young universe — whose rapid expansion pushed the filaments outwards to form an interconnected soap-sud structure of thin films surrounding countless, mostly empty voids.

"Far from being completely frozen in place, the cosmic web's matter can sometimes violently collide. When matter in the web merges, enormous shock waves send charged particles ricocheting through the web's magnetic fields, causing the particles to emit a faint radio wave glow. These shock waves have been spotted around some of the universe's largest galaxy clusters, but until now they were never observed around the web itself.

"'These shock waves give off radio emissions which should result in the cosmic web 'glowing' in the radio spectrum, but it had never really been conclusively detected due to how faint the signals are," Vernstrom said.

***

"Now that the shock waves' existence has been confirmed, they could be used to probe the nature of the enormous magnetic fields that suffuse the web, which play an unknown role in shaping the universe."

Comment: our planetary orbits might be relatively fixed, but our solar system is travelling along as is everything else in the universe. Collisions are widespread.

2225 views

In the original protoplanetary disc:

https://www.sciencealert.com/astronomers-traced-the-origins-of-water-to-a-time-before-t...

"A star 1,300 light-years from Earth might have just revealed one of the Solar System's best-kept secrets.

"It's called V883 Orionis, a young star surrounded by a huge disk of material that will one day coalesce into orbiting planets. It's in that disk that scientists have made an unambiguous detection of water vapor, swirling around with all the other dust and gas destined to become part of an alien world.

"This suggests that the Solar System's water – including that now on Earth – was present in the gaseous cradle from which the Sun was born; that it was here, not just before Earth, but before the Sun, and helped our planet grow.

"We can now trace the origins of water in our Solar System to before the formation of the Sun," says astronomer John Tobin of the US National Radio Astronomy Observatory.

"Water is fairly common throughout the Universe, though Earth in particular wouldn't be the same "pale blue dot" without it. It curls around the planet's surface, permeates the atmosphere as vapor, falls down from the sky. It seems pretty mundane to us, but we wouldn't be able to live without it; almost all life's chemical processes require it.

"It's also an important ingredient in planet formation. Stars are born from clouds of dust and gas in space; a dense clump collapses under gravity and, spinning, starts spooling in more material from the cloud around it that forms into a disk that feeds into the baby star.

"Once the star is done growing, all the other features of the planetary system form from whatever remains of the disk. Dust grains stick together electrostatically, forming larger and larger clumps until the object is massive enough for gravity to take over.

"Water is thought to play a significant role in this process; beyond the point at which water vapor freezes – called the snowline – it coats dust grains as ice, giving them an additional stickiness that helps particles cling together in the very first stages of planetary growth.

***

"'V883 Orionis is the missing link in this case," Tobin says.

"'The composition of the water in the disk is very similar to that of comets in our own Solar System. This is confirmation of the idea that the water in planetary systems formed billions of years ago, before the Sun, in interstellar space, and has been inherited by both comets and Earth, relatively unchanged."

***

"'We conclude that disks directly inherit water from the star-forming cloud and this water becomes incorporated into large icy bodies, such as comets, without substantial chemical alteration," the researchers write in their paper.

"'Although the specific delivery mechanism of water on Earth remains debated (comets and/or asteroids), the [hydrogen isotope ratio] found in V883 Ori is evidence that the water molecules in our Solar System originated in the cold interstellar medium before the formation of the Sun. Therefore, spatially resolved water observations towards young planet-forming disks are crucial in linking the water reservoir and the formation of terrestrial planets.'"

Comment: water with all its strange properties is vital to life. No surprise it is ubiquitous in the universe. But note how much Earth has compared to Mars. Our magnetic field really helps.

2232 views

Whole story is incomplete:

https://www.newscientist.com/article/2363058-how-are-the-atoms-that-form-us-forged-acro...

"The first description of how elements are formed came from Margaret Burbidge, Geoffrey Burbidge, William Fowler and Fred Hoyle (B2FH for short) in 1957. The quartet consisted of an astronomer, a modeller, a nuclear experimentalist and a theorist, reflecting the scientific diversity required to address such a fundamental problem. Together, they described how the combination of intense pressure and heat inside stars could fuse atomic nuclei together, so that heavier elements could be produced from lighter ones. With this the field of nuclear astrophysics was born.

"However, fusion reactions like this couldn’t explain how all elements are formed, only those with an atomic weight up to and including that of iron. Nuclei have a positive charge (because of their protons) and the heavier they get, the harder it is for them to overcome the repulsive electrostatic forces and fuse. Heavier elements do exist in the universe, of course, but the question of exactly how they get there has been open for decades.

"Fred Hoyle suggested that heavier elements could be formed by heavy nuclei capturing neutrons, as the particles’ lack of charge makes them easier to grab than positively charged protons. B2FH proposed two ways that these neutron captures could take place inside stars.

"The first involves stars with a relatively small number of neutrons (around 108 neutrons per cubic centimetre), where neutron-capture reactions take years to occur. This is the so-called s-process (s for slow). In this case, neutrons are captured only by stable isotopes – atoms of the same element with differing numbers of neutrons – and their closest neighbours. Stable isotopes have been studied by nuclear physicists for almost a century and so their properties and how they would work inside a star are well known.

***

"We already had slow and rapid processes, but it seems that the missing piece of the puzzle was something in between. The i-process (short for intermediate) involves a middling amount of neutrons (between 1013 and 1015 per cubic centimetre) and neutron-capture reactions happen over the course of minutes. Adding this process into the mix means that the models fit the new observation data, suggesting it could explain what is going on in those mystery stars uncovered by more powerful telescopes.

***

"We are still far from a full understanding of how heavy elements are produced in the universe. The more we learn, the more we realise that our simple nucleosynthesis picture is incomplete. The introduction of the i-process brings us a step closer to the truth, but we still don’t know where it could take place and how much it contributes to the mix of elements in the solar system. And there’s still much to learn about the r-process too, like whether there are places in the universe outside of neutron star mergers where it could occur. The main challenge comes from the fact that the nuclei involved can’t be produced by our current particle accelerators. However, next-generation facilities, like the Facility for Rare Isotope Beams (FRIB) at Michigan State University, will be able to discover hundreds of new rare isotopes, never-before-produced on Earth."

Comment: still doesn't explain our giant universe, but locally in our galaxy we are learning more and more.

2196 views

They still don't fit into the standard model:

https://www.sciencenews.org/article/ghost-particle-neutrino-discovery-learn

"...much about the neutrino — named in part because it has no electric charge — remains a mystery, including how many varieties of neutrinos exist, how much mass they have, where that mass comes from and whether they have any magnetic properties.

***

"It’s not just neutrino physicists who await those answers. Neutrinos, Riordon says, “are incredibly important both for understanding the universe and our existence in it.” Unmasking the neutrino could be key to unlocking the nature of dark matter, for instance. Or it could clear up the universe’s matter conundrum: The Big Bang should have produced equal amounts of matter and antimatter, the oppositely charged counterparts of electrons, protons and so on. When matter and antimatter come into contact, they annihilate each other. So in theory, the universe today should be empty — yet it’s not (SN: 9/22/22). It’s filled with matter and, for some reason, very little antimatter.

***

SN: "In the first chapter, you list eight unanswered questions about neutrinos. Which is the most pressing to answer?

Riordon: "Whether they’re their own antiparticles is probably one of the grandest. The proposal that neutrinos are their own antiparticles is an elegant solution to all sorts of problems, including the existence of this residue of matter we live in. Another one is figuring out how neutrinos fit in the standard model [of particle physics]. It’s one of the most successful theories there is, but it can’t explain the fact that neutrinos have mass.

Riordon: "All of these questions about neutrinos are sort of coming to a head right now — the hints that neutrinos may be their own antiparticles, the issues of neutrinos not quite fitting the standard model, whether there are sterile neutrinos [a hypothetical neutrino that is a candidate for dark matter]. In the next few years, a decade or so, there will be a lot of experiments that will [help answer these questions,] and the resolution either way will be exciting.

SN: "Neutrinos could also be used to help scientists observe a range of phenomena. What are some of the most interesting questions neutrinos could help with?

Riordon: "There are some observations that simply have to be done with neutrinos, that there are no other technological alternatives for. There’s a problem with using light-based telescopes to look back in history. We have this really amazing James Webb Space Telescope that can see really far back in history. But at some point, when you go far enough back, the universe is basically opaque to light; you can’t see into it. Once we narrow down how to detect and how to measure the cosmic neutrino background [neutrinos that formed less than a second after the Big Bang], it will be a way to look back at the very beginning. Other than with gravitational waves, you can’t see back that far with anything else. So it’ll give us sort of a telescope back to the beginning of the universe."

Comment: so the last chapter for the standard model will be understanding much more about neutrinos. Perhaps it will help dhw understand why the universe is so big.

2204 views

New techniques are teasing them out:

https://www.quantamagazine.org/shadows-in-the-big-bang-afterglow-reveal-invisible-cosmi...

"Nearly 400,000 years after the Big Bang, the primordial plasma of the infant universe cooled enough for the first atoms to coalesce, making space for the embedded radiation to soar free. That light — the cosmic microwave background (CMB) — continues to stream through the sky in all directions, broadcasting a snapshot of the early universe that’s picked up by dedicated telescopes and even revealed in the static on old cathode-ray televisions.

"After scientists discovered the CMB radiation in 1965, they meticulously mapped its tiny temperature variations, which displayed the exact state of the cosmos when it was a mere frothing plasma. Now they’re repurposing CMB data to catalog the large-scale structures that developed over billions of years as the universe matured.

“'That light experienced a bulk of the history of the universe, and by seeing how it’s changed, we can learn about different epochs,” said Kimmy Wu, a cosmologist at SLAC National Accelerator Laboratory.

"... Cosmologists are beginning to look beyond the primary fluctuations in the CMB light to the secondary imprints left by interactions with galaxies and other cosmic structures. From these signals, they’re gaining a crisper view of the distribution of both ordinary matter — everything that’s composed of atomic parts — and the mysterious dark matter. In turn, those insights are helping to settle some long-standing cosmological mysteries and pose some new ones.

“We’re realizing that the CMB does not only tell us about the initial conditions of the universe. It also tells us about the galaxies themselves,” said Emmanuel Schaan, also a cosmologist at SLAC. “And that turns out to be really powerful.”

"Standard optical surveys, which track the light emitted by stars, overlook most of the galaxies’ underlying mass. That’s because the vast majority of the universe’s total matter content is invisible to telescopes — tucked out of sight either as clumps of dark matter or as the diffuse ionized gas that bridges galaxies. But both the dark matter and the strewn gas leave detectable imprints on the magnification and color of the incoming CMB light.

“The universe is really a shadow theater in which the galaxies are the protagonists, and the CMB is the backlight,” Schaan said.

"Many of the shadow players are now coming into relief.

"When light particles, or photons, from the CMB scatter off electrons in the gas between galaxies, they get bumped to higher energies. In addition, if those galaxies are in motion with respect to the expanding universe, the CMB photons get a second energy shift, either up or down depending on the relative motion of the cluster.

"This pair of effects, known respectively as the thermal and kinematic Sunyaev-Zel’dovich (SZ) effects, were first theorized in the late 1960s and have been detected with increasing precision in the past decade. Together, the SZ effects leave a characteristic signature that can be teased out of CMB images, allowing scientists to map the location and temperature of all the ordinary matter in the universe.

"Finally, a third effect known as weak gravitational lensing warps the path of CMB light as it travels near massive objects, distorting the CMB as though it were viewed through the base of a wineglass. Unlike the SZ effects, lensing is sensitive to all matter — dark or otherwise.

"Taken together, these effects allow cosmologists to separate the ordinary matter from the dark matter. Then scientists can overlay these maps with images from galaxy surveys to gauge cosmic distances and even trace star formation.

"In recent years, cosmologists have been puzzled by the fact that the observed distribution of matter in the modern universe is smoother than theory predicts. If the explosions recycling intergalactic gas are more energetic than scientists assumed, as the recent work by Schaan, Amodeo and others seems to suggest, these blasts could be partially responsible for having spread matter more evenly across the universe, said Colin Hill, a cosmologist at Columbia University who also works on CMB signatures. In the coming months, Hill and colleagues at the Atacama Cosmology Telescope plan to unveil an updated map of CMB shadows with a notable jump in both sky coverage and sensitivity." (my bold) dhw read carefully

Comment: The bold is an answer as to why the universe is so big, as dhw questions. The CMB has revealed much of the aspects of the Big Bang

2169 views

Starting from 500 million years ago. comparable patterns:

https://www.universetoday.com/160686/did-supernovae-help-push-life-to-become-more-diverse/

"An idea of cosmic catastrophes having an effect on life is not new. Usually, people think about such events happening to us in modern times. But, there’s a long history of Earth being affected by past cosmic events. It’s likely, for example, that shock waves from supernova explosions set the birth process of our Sun in motion. We experience solar flares and outbursts and how they interfere with our technology. So, why couldn’t supernovae also play a role in the evolution of life? There are a lot of ideas about that, involving both astronomical and biological research.

According to Henrik Svensmark, describing the team’s research, it’s possible that one effect of a supernova is a change in Earth’s climate. “A high number of supernovae leads to a cold climate with a large temperature difference between the equator and polar regions,” he said. “This results in stronger winds, ocean mixing, and transportation of life-essential nutrients to the surface waters along the continental shelves.”

"The team’s paper points out some interesting specifics. It states, “In accordance with the cosmic ray theory, Earth experienced cold glacial periods when the local supernova frequency was high, i.e., high cosmic rays and warm climates when the flux was low. These results suggest that changes in supernovae frequency and, thereby, changes in cosmic rays have significantly influenced the Phanerozoic climate.”

"This proposed influence of supernova explosions extends to the conditions for life. For example, the paper suggests a correlation between past supernova rates and the burial of organic matter in ocean sediments during the last 500 million years. The sequence goes like this: supernovae rates influence climate. Climate influences atmosphere–ocean circulation. That circulation brings nutrients to marine organisms. Nutrient concentrations control bioproductivity (how organisms thrive). Then, as they die, their remains settle into sea sediments, which fossilize and preserve the record of past biological activity.

"All of this appears to correlate with changes in supernova rates. If this link turns out to be solid, then supernovae may well influence climate and the energy available to biological systems. And all that has an influence on marine life.

"So, what evidence is Svensmark’s team offering? They studied the fossil record of ancient shallow marine areas. These were along the edges of oceans and other bodies of water in the Phanerozoic period of Earth’s geologic history. That’s the period of time we’re in now. It began some 542 million years ago. These shallow marine shelves are relevant since most marine life thrives in these areas. By studying the rates of change in species of life they found clear evidence of explosions in biodiversity.

"The team then looked at the astrophysical fossil record of supernovae. They studied supernova frequencies recorded in three data sets of open stellar clusters in the solar neighborhood. Those catalogs contain data about clusters within 850 parsecs of the Sun, with ages 520 million years and younger. The team then correlated the data from the two sets with each other to link higher-than-normal rates of past supernova explosions with climate-influenced changes in biodiversity in shallow marine environments.

" You start with a star at least 8 times the mass of the Sun. When this massive progenitor star reaches the end of its life, it collapses in on itself. The infalling material rebounds off the stellar core and rushes out to space. That cloud of debris scatters all the elements made by the star both before and during the supernova explosion. The event also emits huge amounts of cosmic rays. Those energetic particles eventually arrive in our Solar System. Some smash into Earth’s atmosphere and send showers of ions crashing through the atmosphere. There, they help create the aerosols that form clouds.

"Clouds help regulate solar energy by controlling how much sunlight reaches Earth’s surface. The warmth of the sunlight is one part of the water-warmth-nutrient triad that enables life to form and thrive on the planet. So, in a very real sense, the influence of supernovae is part of the cycle of substantial climate shifts, thanks to the intensity of cosmic rays. According to Svensmark, those changes can be as much as several hundred percent over millions of years. “The new evidence points to a connection between life on Earth and supernovae, mediated by the effect of cosmic rays on clouds and climate”, he said.?

Comment: be sure to look the graph comparing the patterns of different aspects over time from 500 million years ago. I would note the Cambrian explosion slightly predates this study and is a negative factor for their varied correlation theory. The graph shows low supernova activity in that time period. In view of this finding, lets return to our discussion about God's control of cosmologic events and environmental events. This study says the cosmologic events change the Earth's environment. I stand by my theory that God does interfere with or control these events. They happen and whatever results pop up God designs for them, no luck ever needed. This also tends to silence dhw's complaint that the huge universe size and
millions of parts are unexplained. This clearly is a partial explanation.

1987 views

More review:

https://www.discovermagazine.com/the-sciences/how-did-the-universe-begin?utm_source=acs...

"Our growing knowledge of physical laws has allowed us to rewind the tape on the universe, tracing its evolution back to within a fraction of a second after the Big Bang. Here, however, when the sum total of matter and energy coalesces in a ball of infinite density and temperature, the equations of general relativity break down.

"As a theory, “the Big Bang leaves out the bang,” physicist Brian Green writes in The Fabric of the Cosmos. Whatever happened in that instant, let alone before that moment, is anyone’s (well-reasoned) guess — and there is no shortage of guesses of how the universe began.

"First, a caveat: Many experts argue that the word “before” misses the mark. It assumes there was some pre-existing time separate from the universe, when really, time and space may have emerged out of the universe.

"In this view, the question — “what came before the big bang?” — is literally meaningless. Stephen Law, an Oxford philosopher, has suggested in interviews that what we need is not an answer to these kinds of questions, but “a kind of therapy, an explanation that will make us realize why it’s time to stop asking the question.”

"The idea pushes human language and intuition to their breaking point, but we can try to make sense of it with a favorite analogy of the late physicist Stephen Hawking: Wondering what happened before the big bang is like wondering what’s south of the South Pole. It’s not even accurate to say there is nothing farther south; the point is that the question itself is nonsensical. We’re trying to pin down something that simply doesn’t exist.

***

"One prominent advocate of this perspective is Alexander Vilenkin, a cosmologist at Tufts University. In a 1982 paper, written for an audience of professional physicists, he conceded that “the concept of the universe being created from nothing is a crazy one.”

"Nevertheless, he argued that the laws of physics alone could have given rise to all we see around us.

"As MIT physicist Alan Lightman has described it, “the entire universe could have ‘suddenly’ appeared from wherever things originate in the impossible-to-fathom haze of quantum probabilities.”

"Still, you might suspect that this “nothing,” if it was compatible with the creation of reality as we know it, was “something” after all.

"David Albert, a philosopher at Columbia University, has argued exactly that: “If what we formerly took for nothing turns out, on closer examination, to have the makings of protons and neutrons and tables and chairs and planets and solar systems and galaxies and universes in it, then it wasn’t nothing, and it couldn’t have been nothing, in the first place.”

"When it comes to understanding the concept of a universe from nothing, there’s an important difference between philosophical nothing and physical nothing. Namely, the latter still includes the laws of nature required for cosmic genesis.

"Even granting Albert’s point, though, we’re merely kicking the can down the road. Whatever our universe came from, that too must have come from something else (at least according to the commonsense expectations of feeble human brains)."

Comment: multiverse, cyclic universe and Penrose special cyclic form are mentioned for completeness. Guth et al paper simply said there was no before, before the Big Bang. They simply could not prove one nad neither would anyone else. Brian Green sets up the Big Bang theory backwards. From my viewpoint, if space and time started the beginning it came from nothing. God made it happen.

1975 views

The telescopes we have see back just so far:

https://bigthink.com/starts-with-a-bang/edge-of-the-universe/?utm_campaign=swab&utm...

"Despite everything we’ve learned about our Universe, there are many existential questions that remain unanswered. We don’t know if our Universe is finite or infinite in extent; we only know that its physical size must be greater than the portion we can observe. We don’t know whether our Universe encompasses all that exists. And we remain ignorant about what happened in the earliest stages of all: in the first tiny fraction-of-a-second of the hot Big Bang, as we lack the necessary evidence to draw a robust conclusion.

"But one thing we are certain about is that the Universe has an edge: not in space, but in time. Because the hot Big Bang occurred at a known, finite time in the past — 13.8 billion years ago, with an uncertainty of less than 1% — there’s an “edge” to how far away we can see. Even at the speed of light, the ultimate cosmic speed limit, there’s a fundamental limit to how far back we can see. The farther away we look, the farther back in time we’re able to see. Here’s what we see as we approach the edge of the Universe.

***

"But as we look farther and farther away, we start to see how the Universe grew up to become this way. As we look to greater distances, we find that the Universe is slightly less clumpy and slightly more uniform, particularly on larger scales. We see that galaxies are lower in mass and less evolved; there are more spirals and fewer elliptical galaxies. On average, there are greater proportions of bluer stars, and the star formation rate was higher in the past. There’s less space between galaxies, on average, but the overall masses of groups and clusters is smaller at earlier times.

***

"We take for granted, today, that space is transparent to visible light, but that’s only true because it isn’t full of light-blocking material, like dust or neutral gas. But at early times, before enough stars had formed, the Universe was full of neutral gas, and hadn’t become fully ionized by the ultraviolet radiation from these stars. As a result, a lot of the light we see is obscured by these neutral atoms, and it’s only once enough stars have formed that the Universe becomes fully reionized.

"This is, in part, why infrared telescopes, such as NASA’s newest flagship mission, the JWST, are so crucial to investigating the early Universe: there’s an “edge” to where we can see in the wavelengths we’re familiar with.

***

"JWST has now taken us even farther, showing us galaxies as far back as 330 million years after the Big Bang, where they still appear large, evolved, and are not quite “pristine” in terms of the elements that are present within them. There must still be stars and galaxies out there beyond even what JWST has shown us so far.

"Beyond those limits of what our current telescopes can see, however, we can still measure the indirect signs that stars have formed: through the emission of light from hydrogen atoms themselves, which only occurs when stars form, ionization occurs, and then the free electrons recombine with the ionized nuclei, emitting light in the aftermath of that.

***

"The very first stars of all, in the rare regions that grow in mass density the fastest, are expected to come about between 38 and 40 billion light-years away, corresponding to times just 50-to-100 million years after the Big Bang.

"Before that, the Universe was only dark, full of neutral atoms, and radiation from the Big Bang’s leftover glow.

***

"And before that, 46 billion light-years away, we come to the earliest stages of all: the ultra-energetic state of the hot Big Bang, where the first atomic nuclei, protons and neutrons, and even the first stable forms of matter were created. At these stages, everything can only be described as cosmic “primordial soup,” where every particle and antiparticle in existence can be created from pure energy.

"What lies beyond the frontier of this high-energy soup, however, remains a mystery. We have no direct evidence for what occurred in those earliest stages, although many of the predictions of cosmic inflation have been indirectly confirmed. The edge of the Universe, as it appears to us, is unique to our perspective; we can see back 13.8 billion years in time in all directions, a situation that depends on the spacetime location of the observer who’s looking at it.

"The Universe has many edges: the edge of transparency, the edge of stars and galaxies, the edge of neutral atoms, and the edge of our cosmic horizon from the Big Bang itself. We can look as far away as our telescopes can take us, but there will always be a fundamental limit. Even if space itself is infinite, the amount of time that’s passed since the hot Big Bang is not. No matter how long we wait, there will always be an “edge” that we’ll never be able to see past."

Comment: We cannot see the current edge, not enough light-years of time, so Siegel has looked back to our beginning. He shows how the universe evolved. More evidence God evolves His goals.

1955 views

Hubble expansion rate faster than the speed of light at far out edges:

https://www.discovermagazine.com/the-sciences/how-big-is-the-observable-universe?utm_so...

"Our universe is about 13.8 billion years old, and the observable bubble of that cosmos has a diameter of about 93 billion light-years across. And we all know the famous maxim from Albert Einstein’s special theory of relativity: nothing can travel faster than light.

***

"Locally, no galaxy is moving. But the space between them is. So there are no restrictions here based on the speed of light because they’re literally not moving. There’s no limit to how quickly space can expand (because “expanding” isn’t a motion as far as relativity is concerned) and so the universe can grow as quickly as it pleases.

"Essentially, the universe is so big because it can expand faster than light. In fact, it’s doing so today. We measure the present-day expansion rate of the universe with something called the Hubble constant, which is around 68 kilometers per second per megaparsec.

"That means for every megaparsec in distance you get away from the Milky Way, the universe’s expansion speed will increase by 68 km/s. A galaxy two megaparsecs away appears to recede at 136 km/s, a galaxy ten megaparsecs away will recede at 680 km/s, and so on.

"The Hubble constant guarantees that once you reach a certain distance — about 13 billion light-years (a distance known as the Hubble radius) — galaxies will appear to move away from us faster than light.

***

"The light from galaxies beyond the Hubble radius was released billions of years ago and is only just now reaching the Earth. We calculate where these galaxies are right now based on our understanding of cosmology, and that’s how we’re able to estimate the size of the universe. The fact that they appeared to move faster than light means that any light that they send now will never reach us — because that light will not be able to overcome the expansion of the universe.

"Since most of the universe is beyond the Hubble radius, all those galaxies are forever out of reach. As time goes on, those galaxies will, one by one, disappear entirely from view. Not through any cheating of the laws of physics, but through simple (and inevitable) stretching."

Comment: dhw wonders why God made it so big. Because that is what God wanted.

1782 views

Still no agreement between methods:

https://www.sciencenews.org/article/supernova-universe-expansion-hubble-constant

"Images of the supernova Refsdal have popped up multiple times in the constellation Leo, thanks to light from the stellar explosion wending its way through the gravitational field of a cluster of galaxies. Analyzing delays between Refsdal’s appearances provides a new measurement of the Hubble constant, researchers report online May 11 in Science. That constant describes how quickly galaxies are flying away from each other as the universe expands. The new measurement is now contributing to debate over how fast the universe is expanding.

***

"Instead of a single burst in the sky, Kelly says, “We saw four images of it.” They formed a pattern known as an Einstein Cross. The cross resulted because the gravity of a cluster of galaxies between the Earth and Refsdal distorts space and time to create a gravitational lens that deflects the light on its way to us.

"The location and arrival times of the images we see depend on three things: the distribution of matter in the galaxy cluster that makes up the lens; the distances between Earth, the lens and the supernova; and the Hubble constant. The combined effect on the light from Refsdal is so strong that in 2014, Kelly predicted that one more image from the supernova would be delayed by another year. Sure enough, light from Refsdal showed up in the sky again in 2015

"The new calculations from Kelly and colleagues greatly improve a 2018 measurement of the Hubble constant using Refsdal’s appearances, putting it at about 66.6 kilometers per second per megaparsec, based on gravitational lens models that most closely matched their observations. “The meticulous modeling of the [lens] system, along with the gravitational forces it generates, have allowed [the team] to decrease the margin of error in estimating the Hubble constant by more than a factor of two,” says astronomer Vivian Miranda of Stony Brook University in New York who was not involved in the new study.

"Studies that estimate the Hubble constant in other ways don’t agree well with each other. One method that relies on ancient light left over from early cosmic times suggests that the universe is expanding at about 67 km/s/Mpc. That’s close to the value Kelly’s group found. But an expansion estimate that uses the distances to supernovas based on their brightness comes in around 74 km/s/Mpc

“'The predicted value of the Hubble constant is highly sensitive to the dynamics of the universe, both in the distant past and the recent present,” Miranda says. “If our understanding of the universe is accurate, all the various methods of measuring the Hubble constant should align.”

"Settling the discrepancy between different values of the Hubble constant is crucial to explaining things like dark energy, which appears to be accelerating the expansion of the universe.

***

“'This is the first example of this kind of measurement,” Kelly says. “It sets the stage for additional measurements and increased precision,” which could deepen astronomers’ insights into our ever-expanding universe."

Comment: tying two measurements together as one number will relieve some theorists, but the major point is our universe is dramatically active and constantly expanding ever since the Big Bang. We live in an arrow of direction. Which means the edge of what we can see will be less and less of the whole universe.

1374 views

Giant gas bubbles:

https://www.sciencealert.com/giant-bubbles-surrounding-the-milky-way-are-more-complex-t...

"Extending high above and below the Milky Way's galactic plane, a pair of huge, symmetrical blobs of gas stretch out like the lobes of a cosmic hourglass, glowing faintly with an X-ray radiance.

"They're known as eROSITA bubbles, named after the X-ray telescope that spotted them in 2020, and are located in the Milky Way's massive shell of gas, or 'circumgalactic medium', extending some 45,661 light-years either side of the galactic center.

"The energetic gasses making up the bubbles were assumed to have a fairly even, if somewhat high temperature throughout, caused by the shock of its passage through the medium. Though a surprising discovery now makes them seem more complex than first appears.

"Data from the Suzaku satellite, run by NASA and the Japanese Aerospace Exploration Agency (JAXA), suggests the X-ray glow of the bubbles isn't because they're hotter than their surrounds as assumed, but rather that the gasses simply have a higher density.

***

"Previously, a temperature difference between the eROSITA bubbles and the surrounding galactic halo was assumed because of the relative brightness of the bubble shells. According to the newer method of analysis, that brightness is down to the higher density of the gas inside the bubbles and not heat.

"The research also sheds some light on how these bubbles formed: readings of non-solar ratios of neon-oxygen and magnesium-oxygen in the bubble shells suggest these bubbles were formed by nuclear star formation, or the injection of energy from other objects (like massive stars for example).

"It gives less credence to a previous hypothesis that a supermassive black hole and its associated activity – high-speed winds creating as objects are caught in the black hole's pull – are behind the creation of the eROSITA bubbles.

"'Our data supports the theory that these bubbles are most likely formed due to intense star formation activity at the galactic center, as opposed to black hole activity occurring at the galactic center," says astronomer Smita Mathur, from Ohio State University.

"It's thought that the eROSITA bubbles are connected to smaller but similarly shaped blobs of gas called Fermi bubbles, which were discovered in 2010 with NASA's gamma-ray telescope. Astronomers have suggested that the same events created all of these galactic bubbles, so the findings are relevant here too."

Comment: there is lots to learn about the Milky Way. We have no idea how much will apply to other spiral galaxies. Is the Milky Way ordinary or special?

1380 views

Our neighboring galaxy influences us:

https://www.sciencealert.com/the-large-magellanic-cloud-shapes-the-milky-way-in-ways-we...

"Our galaxy's largest nearby companion is the Large Magellanic Cloud (LMC), a dwarf galaxy visible to the naked eye in the Southern Hemisphere.

"In recent years, new theoretical research and better observational capabilities have taught astronomers a great deal about our (not-so-little) neighbor.

***

"Weighing in at 10-20 percent the mass of our own galaxy, the LMC is worth taking seriously. Astronomers believe that it's on its first orbit around the Milky Way.

"Before that orbit began, it was a spiral galaxy in its own right. Interacting with the Milky Way distorted its spiral arms, though it still features a strong central bar as evidence of its previous structure.

"The Milky Way, too, was changed by the interaction. The stars and stellar streams nearest to the LMC had their orbits deflected, for example, and there were larger, structural changes to the Milky Way too.

"Because the Milky Way isn't rigid, but rather made up of stars, dust, gas, and rock in varying densities, parts of the galaxy closer to the LMC were affected more than distant parts.

***

"The fact that it's difficult doesn't mean astronomers are giving up. The LMC's size and proximity mean that its perturbations on our home galaxy ought to be quite significant. But how to find them?

"The answer may lie, in part, in the most recent Gaia data, which showed a peculiar 'striped' pattern in the position and velocity of stars in the Milky Way's galactic halo. The halo is a spherical region that encircles the galactic disk and contains stars at a much lower density than the more populous disk does.

"These stripe patterns are believed to be the traces left behind by long-dead galaxies that merged with the Milky Way in the ancient past, like the hypothesized Gaia-Enceladus galaxy.

When the LMC passed near to the Milky Way in the more recent past, it should have left distortions in those stripes, and that's what astronomers like Vasiliev are hoping to find.

***

"As for the future of the Milky Way and the LMC, they are, ultimately, on a collision course. The LMC will merge with the Milky Way in a few billion years, delivering more mass and metallicity to the Milky Way's halo.

"Of course, this dramatic event will be only a precursor to the even larger merger in store for the Milky Way, as the Andromeda Galaxy will, at that point, be on its final approach toward us.

"If there is a moral to this story, it's that no galaxy is an island. The Milky Way's neighbors are helping to shape its past, present, and future, and astronomers are making an effort to take those effects into account as they study of our home galaxy."

Comment: although a large somewhat isolated galaxy we are influenced by our neighbors. It is important to see how.

1376 views

It is a battle of magnetic forces:

https://www.quantamagazine.org/the-tiny-physics-behind-immense-cosmic-eruptions-20230515/

"During fleeting fits, the sun occasionally hurls a colossal amount of energy into space. Called solar flares, these eruptions last for mere minutes, and they can trigger catastrophic blackouts and dazzling auroras on Earth. But our leading mathematical theories of how these flares work fail to predict the strength and speed of what we observe.

"At the heart of these outbursts is a mechanism that converts magnetic energy into powerful blasts of light and particles. This transformation is catalyzed by a process called magnetic reconnection, in which colliding magnetic fields break and instantly realign, slingshotting material into the cosmos. In addition to powering solar flares, reconnection may power the speedy, high-energy particles ejected by exploding stars, the glow of jets from feasting black holes, and the constant wind blown by the sun.

***

"Nearly all known matter in the universe exists in the form of plasma, a fiery soup of gas where infernal temperatures have stripped down atoms into charged particles. As they zip around, those particles generate magnetic fields, which then guide the particles’ movements. This chaotic interaction knits a scrambled mess of magnetic field lines that, like rubber bands, store more and more energy as they’re stretched and twisted.

***

"More recently, observations from NASA’s magnetospheric satellites identified this speedier reconnection happening even closer to home, in Earth’s own magnetic field. Those observations, along with evidence from decades of computer simulations, confirm this “fast” reconnection rate: In more energetic plasmas, reconnection occurs at roughly 10% of the speed at which magnetic fields propagate — orders of magnitude faster than Sweet and Parker’s theory predicts.

"The 10% reconnection rate is observed so universally that many scientists consider it “God’s given number,” said Alisa Galishnikova, a researcher at Princeton. But invoking the divine does little to explain what’s making reconnection so fast.

***

"The first paper, published in Communications Physics, describes how the voltage induces a magnetic field that draws electrons away from the center of the two colliding magnetic regions. That diversion produces a vacuum that sucks in new field lines and pinches them in the center, allowing the magnetic slingshot to form more quickly.

“'That picture was missed … [but] it was staring at us in the face,” said Jim Drake, a plasma physicist at the University of Maryland. “This is the first convincing argument I’ve ever seen.”

"In the second paper, published in Physical Review Letters, Liu and his undergraduate research assistant Matthew Goodbred describe how the same vacuum effect emerges in extreme plasmas containing different ingredients. Around black holes, for example, plasmas are thought to consist of electrons and equally massive positrons, so the Hall effect no longer applies. Yet, “magically, reconnection is still working in a similar way,” Liu said. The researchers propose that within these stronger magnetic fields, most of the energy is spent accelerating particles rather than heating them — again creating a pressure depletion that yields the divine 10% rate.

“'It’s a major milestone theoretically,” said Lorenzo Sironi, a theoretical astrophysicist at Columbia University who works on computer simulations of high-energy plasma jets. “This gives us confidence … that what we’re seeing in our simulations is not crazy.”

***

"Now, scientists hope theoretical advances such as Liu’s will lead to models of magnetic reconnection that more accurately reflect nature. But while his theory aims to settle the reconnection-rate problem, it does not explain why some field lines collide and trigger reconnection but not others. It also doesn’t describe how the outflowing energy is divvied up into jets, heat and cosmic rays — or how any of this works in three dimensions and on larger scales. Still, Liu’s work shows how, under the right circumstances, magnetic reconnection can be efficient enough to drive ephemeral but violent celestial outbursts."

Comment: we are back to dhw's question, why did God make the universe so big and complex? We are still trying to understand the complexity As for the 'why' question. God always has His reasons. This work is poking into just that.

1408 views

Our planets have slightly shifting orbits. Can they crash?:

https://www.quantamagazine.org/new-math-shows-when-solar-systems-become-unstable-20230516/

"For centuries, ever since Isaac Newton formulated his laws of motion and gravity, mathematicians and astronomers have grappled with this issue. In the simplest model of the solar system, which considers only the gravitational forces exerted by the sun, the planets follow their elliptical orbits like clockwork for eternity. “It’s kind of a comforting picture,” said Richard Moeckel, a mathematician at the University of Minnesota. “It’s going to go on forever, and we’ll be long gone, but Jupiter will still be going around.”

"But once you account for gravitational attraction between the planets themselves, everything gets more complicated. You can no longer explicitly calculate the planets’ positions and velocities over long periods of time, and must instead ask qualitative questions about how they might behave. Might the effects of the planets’ mutual attraction accumulate and break the clockwork?

***

"...in three papers that together exceed 150 pages, Guàrdia and two collaborators have proved for the first time that instability inevitably arises in a model of planets orbiting a sun.

“'The result is really very spectacular,” said Gabriella Pinzari, a mathematical physicist at the University of Padua in Italy. “The authors proved a theorem that is one of the most beautiful theorems that one could prove.” It could also help explain why our solar system looks the way it does.

***

"The new papers tackle a true n-body problem — showing that instability arises in a planetary system where three small bodies revolve around a much larger sun. Even though the size and shape of the orbits might spend a long time oscillating around fixed values, they will eventually change dramatically.

"This had been expected — it was widely believed that stability and instability coexist in this kind of model — but the mathematicians were the first to prove it.

***

"The results provide a potential explanation for why the planets in our solar system have orbits that all lie nearly in the same plane. It shows that something as simple as a large angle of inclination can be a source of a great deal of instability, on multiple counts. “If you start with a situation where the mutual inclinations are quite big, then you will destroy the system quite ‘quickly,’” Chenciner said. “It would have been destroyed hundreds, thousands of centuries ago.”

***

"Mathematicians now hope to use Clarke, Fejoz and Guàrdia’s techniques to prove instability in models that look more like our own solar system. These kinds of results are becoming particularly meaningful as astronomers uncover more and more exoplanets orbiting other stars, showcasing a broad range of configurations. “It’s like an open lab,” said Marian Gidea, a mathematician at Yeshiva University. “To understand on paper what types of evolutions of planetary systems can happen, and to compare that with what you are able to observe — it is very exciting. It gives a lot of information about the physics of our universe, and about how much of this our mathematics is able to capture through relatively simple models.”

***

"The ultimate goal would be to prove instability in our own solar system. “I wake up in the middle of the night thinking about it,” Clarke said. “I would say that would be the real dream, but it would be a nightmare, wouldn’t it? Because we’d be screwed.”

Comment: stability within instability, and our planets stay in their orbits. Did this happen by chance? I think not.

1371 views

Time is is settled:

https://www.scientificamerican.com/article/the-universe-began-with-a-bang-not-a-bounce-...

"So which scenario is correct? The most widely accepted explanation for the history of the universe has it beginning with a big bang, followed by a period of rapid expansion known as cosmic inflation. According to that model, the glow left over from when the universe was hot and young, called the cosmic microwave background (CMB), should look pretty much the same no matter which direction you face. But data from the Planck space observatory, which mapped the CMB from 2009 to 2013, showed unexpected variations in the microwave radiation. They could be meaningless statistical fluctuations in the temperature of the universe, or they might be signs of something interesting going on.

***

"In an LQC model, a precursor to our universe might have contracted under the force of gravity until it became extremely compact.

***

"If that happened, says physicist Ivan Agullo of Louisiana State University, it should have left a mark on the universe. Agullo, who was not affiliated with either of the recent analyses, has proposed that the mark would turn up in a feature in the CMB data known as the “bispectrum,” a measure of how different portions of the universe would have interacted in a bouncing scenario. The bispectrum would not be apparent in an image of the CMB, but it would show up in analyses of the frequencies in the ancient CMB microwaves.

***

"Although lots of other bouncing cosmos models may still be viable, the failure to find a significant bispectrum means that models that rely on LQC to deal with the anomalies in the CMB can be ruled out. It’s a sad result for Agullo, who had high hopes of finding concrete evidence of a bouncing universe. But Paola Delgado, a cosmology Ph.D. candidate at Jagiellonian University in Poland, who worked on the new analysis that was co-authored by Durrer, says there’s one potential upside. “I heard for a long time that [attempts to merge quantum physics and cosmology] cannot be tested,” Delgado says. “I think it was really nice to see that for some classes of models, you still have some contact with observations.”

"Ruling out signs of an LQC-driven cosmic bounce in Planck data means the CMB anomalies remain unexplained. But an even larger cosmic issue lingers: Did the universe have a beginning at all? As far as advocates of the big bang are concerned, it did. But that leaves us with the inscrutable singularity that started everything off.

***

"But a critical flaw lurks in the idea of an eternally cycling universe, according to physicist William Kinney of the University at Buffalo, who co-authored the second recent analysis. That flaw is entropy, which builds up as a universe bounces. Often thought of as the amount of disorder in a system, entropy is related to the system’s amount of useful energy: the higher the entropy, the less energy available. If the universe increases in entropy and disorder with each bounce, the amount of usable energy available decreases each time. In that case, the cosmos would have had larger amounts of useful energy in earlier epochs. If you extrapolate back far enough, that implies a big bang–like beginning with an infinitely small amount of entropy, even for a universe that subsequently goes through cyclic bounces. (If you’re wondering how this scenario doesn’t violate the law of conservation of energy, we’re talking about available energy. Although the total amount of energy in the cosmos remains static, the amount that can do useful work decreases with increasing entropy.

***

“'I feel like we’ve demonstrated something fundamental about the universe,” Kinney says, “which is that it probably had a beginning.” That implies a big bang occurred at some point, even if that event happened many bouncing universes ago, which in turn suggests that it took a singularity to get everything going in the first place.

***

"Cosmologist Nelson Pinto-Neto of the Brazilian Center for Physics Research, who has studied bouncing and other cyclic models, agrees that the Planck data likely rule out a bounce under loop quantum cosmology, but he’s more sanguine on the question of a cyclic universe. “Existence is a fact. We are all here and now. Nonexistence is an abstraction of the human mind,” Nelson says. “This is the reason I think that a [cyclic universe], which has always existed, is simpler than one that has been created. However, as a scientist, I must be open to both possibilities.;” (my bold)

Comment: so the battle rages even though the evidence is overwhelmingly in favor of the Big Bang. My bold above tells the reason. Don't even let God's toe in the door!!!

1356 views

There is nothing beyond us:

https://bigthink.com/starts-with-a-bang/what-universe-expanding-into/?utm_campaign=swab...

"But if the Universe has been expanding for all this time, what is it that the Universe is expanding into? That’s a common question that people have.

“One question comes to mind, just exactly what is the universe expanding into?”

"The short, one-word answer to this question is as pithy as it is unsatisfying: itself. The Universe expands into itself, rather than into any definable “outside” medium. This is another example where the science of General Relativity defies our common experience and intuition, so let’s see if we can help you understand it a little bit better by unpacking the science behind the expanding Universe.

***

"Although, in theory, the Universe could have been either expanding or contracting, expansion is what it turns out it’s actually doing.

***

"A slightly better analogy, therefore, is to consider a fully three-dimensional object that expands: like a ball of raisin bread dough, i.e., bread dough with raisins distributed all throughout it. As the dough leavens, it expands, but the raisins within it don’t. The raisins simply move farther away from one another in all three dimensions. If you’re within a raisin, you see: nearby raisins recede slowly, intermediate-distance raisins receding more rapidly,
and the most distant raisins receding most quickly of all, even though the raisins are actually stationary relative to the expanding dough. If the dough were transparent, it would behave like the fabric of space, while the raisins behave like individual galaxies within the expanding Universe.

***

"It’s that last point, about the dough expanding into “something,” that provides the greatest difficulty in making an analogy with the expanding Universe. Whereas the dough is an object that’s embedded within a larger reality (the full scope of three-dimensional space), the Universe itself is simply all there is. Or, at the very least, all that there needs to be.

"One way to overcome this difficulty is to imagine, instead of a ball of dough (embedded with raisins) in our three-dimensional Universe, is to imagine a three-dimensional Universe that is entirely filled with this raisin-embedded dough.

***

"...there’s no “outside” or “beyond” to the cosmos; it is simply all there is and ever was and ever will be.

"And that’s the biggest thing to wrap your head around. When it comes to the expanding Universe, it isn’t expanding into anything, because there isn’t anything else above, beyond, outside, or before or after space-and-time. All at once, it’s both everything and nothing: everything because it contains all that exists, and nothing because if you take all the matter, radiation, and quanta that exist within it away, it still persists: the nothingness of empty space itself. That’s what the fabric of spacetime is, and that’s why it can’t expand “into” anything: it itself is a fundamental part of our reality.

"That’s why, when you ask, “What is the Universe expanding into?” the best answer we can give is “itself.” The key realization is to stop thinking of the Universe as a thing that evolves in some larger, greater context; it’s perfectly reasonable to think of it as all there is, and to simply recognize that expansion and contraction are properties inherent to space itself."

Comment: our universe is all that exists. We cannot know what is outside, if there is an outside.

1432 views

Five specific items had to be perfect or the universes would not be here in its current form:

https://bigthink.com/starts-with-a-bang/5-what-ifs-change-cosmic-history/?utm_campaign=...

"1.) What if the Universe were actually perfectly uniform when it was born? This one is not something that’s greatly appreciated: the Universe, as we know it, couldn’t have been born perfectly smooth. If we had possessed an exactly equal amount of matter-and-antimatter-and-radiation everywhere, at all locations in space, going all the way back to the earliest moments of the hot Big Bang, every point in the Universe would experience an equal gravitational force pulling on it in all directions. In other words, the idea of gravitational growth and collapse relies on an initial imperfection to grow from. Without the seed, you can’t get the desired end result, like a star, galaxy, or something even larger.

***

"If our Universe were born exactly, perfectly uniform, there would be no structure, no stars, and no interesting chemical reactions to speak of anywhere in the cosmos.

***

"2.) What if the expansion rate and the effects of gravitation were less perfectly balanced? This one is a bit tricky. We normally think of the Universe as a fairly stable place, but that’s only because there are two things that have been so well-balanced for so long: the rate at which the Universe expands and the decelerating effects of all the matter and radiation in the Universe. Today, these two effects don’t match, and that’s why we say the expansion of the Universe is accelerating.

***

"What’s remarkable is when we consider how perfectly balanced these two quantities must have been. Today, the Universe has a density of about 1 proton per cubic meter of space. But early on, it had a density that was more like quintillions of kilograms per cubic centimeter of space. If you would have increased or decreased that density by just 0.00000000001%, the Universe would have: recollapsed on itself, ending in a Big Crunch after less than 1 second, in the case of an increase, or expanded so quickly that no protons and electrons would ever have found one another to form even a single atom in the Universe, in the case of a decrease.
This incredible balance, along with the need for it, highlights just how precarious our existence in this Universe is.

***

"3.) What if there had been exactly equal amounts of matter and antimatter? This is another problematic one for us, and in fact it’s one of the greatest unsolved problems in all of physics: why do we live in a Universe with more matter than antimatter? This puzzle has many possible resolutions, but no definitive answer. What we can say, for certain, is that:

"in the early stages of the hot Big Bang, the Universe should have been perfectly symmetric between matter and antimatter, and that somehow, some process occurred that resulted in the existence of approximately 1,000,000,001 matter particles for every 1,000,000,000 antimatter particles, and when the excess annihilated away, we were left with that tiny bit of matter amidst a leftover bath of radiation. That radiation still survives, as does the matter, which is why we can reconstruct what happened at early times.

***

"If our Universe hadn’t created a matter-antimatter asymmetry early on, none of the remarkable steps that came afterward to lead to our existence could have taken place.

***

"4.) What if there hadn’t been any dark matter?...Most of us think about dark matter as the “glue” that holds the largest structures in the Universe together: things like the cosmic web and enormous galaxy clusters. But dark matter also does two particularly important things we don’t typically think about: it provides the majority of the gravitational mass that both forms all galaxies in the Universe and continues to hold them together, and it prevents structure from being “washed out” by the interactions that exist between normal matter and radiation.

***

'In a Universe with no dark matter, only that first generation of stars would exist, meaning there would be no rocky planets, no biochemistry, and no life.

***

"5.) What if dark energy weren’t constant in space or time? This is the one possibility that’s still on the table for our Universe: that dark energy might evolve in some fashion. To the best of our observational limits, it certainly looks and behaves like a cosmological constant — as a form of energy inherent to the fabric of space itself — where the energy density remains constant in time and all throughout space.

***

"If dark energy strengthens, the Universe could rip apart. If dark energy weakens or reverses its sign, the Universe could yet recollapse. And if dark energy decays, the Universe as we know it could end. None of these things have happened yet, but if the Universe were only slightly different, any one of them could have taken place in the past, precluding our existence from occurring at all.

***

"All of this, when taken together, leads us to a fascinating conclusion: if any of these things were — in any way — substantially different from the way they are, it would have been a physical impossibility for human beings to have arisen as we did within the Universe."

Comment: a different perspective on the fine tuning of the formation of this universe. It was designed.

1437 views

New discoveries:

https://www.sciencealert.com/hundreds-of-mystery-structures-found-at-the-heart-of-the-m...

"An investigation into the mystery filaments hanging in space around the heart of the Milky Way has turned up an entirely new population of them, aligned along the galactic plane and pointing in the direction of the galactic center.

"The magnetized strands are likely the remnants of an outflow from the supermassive black hole Sagittarius A* interacting with the surrounding gas a few million years ago, says astrophysicist Farhad Yusef-Zadeh of Northwestern University.

"Although Sgr A* is pretty quiet now, these remnants suggest that our galaxy's center has been active recently – on cosmic timescales, that is. And their discovery also means that our galaxy's center, as wild and wooly as we already knew it to be, has more fascinating secrets lurking within.

***

"Filaments floating about the galactic center aren't a novel finding. In fact, Yusuf-Zadeh with two of his colleagues discovered them in the 1980s – around 1,000 long, vertical, magnetic structures up to around 150 light-years in length, and hanging in surprisingly orderly arrangements, like harp strings. These could be the result of winds gusting from an active supermassive black hole, or turbulence in the intergalactic medium, stirred by the motion of galaxies.

"The new population was discovered in data collected by the MeerKAT radio telescope in South Africa. Yusuf-Zadeh and his team were cleaning up the data, removing the background to make the vertical filaments more visible, when something else emerged.

"That something was a new population of galactic 'harp strings'.

***

"Although all of the structures are magnetized, the vertical ones accelerate particles to near light speed, while the newly discovered horizontal ones appear to emit thermal radiation.

"They're also radially arranged just on one side of the galactic center, pointing back towards Sgr A*, compared to the parallel arrangement of the vertical ones, arrayed all around the galactic center. This radial arrangement also seems linked to the orientation of Sgr A*. It seems to point, not just at the black hole, but at a radial outflow driven by the astrophysical jets that erupt from around a black hole when it is actively accreting material.

"'One of the most important implications of radial outflow that we have detected is the orientation of the accretion disk and the jet-driven outflow from Sagittarius A* along the galactic plane," Yusuf-Zadeh says.

***

"There are other signs Sgr A* fired up its jets in the relatively recent past, such as giant bubbles that extend vast distances above and below the galactic plane. The radial dashes, according to Yusuf-Zadeh and his colleagues, could be the result of ram-pressure produced by a jet-driven outflow from Sgr A*. And analysis of their extent and position suggest that this took place around 6 million years ago.

"'We think they must have originated with some kind of outflow from an activity that happened a few million years ago," Yusef-Zadeh says. "It seems to be the result of an interaction of that outflowing material with objects near it."

"Given new structures seem to be emerging as we build and refine the technology to detect them, we're far from knowing the complete history and dynamics of the center our our Milky Way."

Comment: the Milky Way is vast, very old, but its center is still acting very young

1315 views

The paper says it is, Hossenfelder says no, no:

https://www.patreon.com/Sabine/posts?filters[search_query]=big%20bounce&filters[all...

"The paper is the report of an experiment. For this experiment, they trapped two clouds of about 20 thousand Rubidium atoms on a chip with a bunch of electric and magnetic fields. The clouds have the shape of a cigar and are a fraction of a millimetre long. They couple the two clouds together with more electromagnetic fields and then decouple them. This creates a kind of shock wave traveling through the clouds. Then they measure the correlations between the clouds after various time intervals.

"The rest is interpretation. The interpretation says that perturbations in the atom clouds behave as if they were perturbation in a curved space-time, if you identify the speed of sound in the gas clouds with the speed of light in space-time. This is because you can use the electric and magnetic fields to make the speed of sound in the gas dependent on the place. So, you can manipulate how the perturbations travel kind of like it would happen in a curved space-time. Then you can call that a “quantum simulation” of a curved space-time.

"Here’s what they don’t say in the press release. These atom clouds that they used for the experiment are cigar shaped which means they’re effectively one-dimensional. But there’s no gravity in only one dimension of space. You don’t have to take my word for it, you can look it up in Weinberg’s book on general relativity. So even the link to a curved space-time is somewhat of a stretch.

***

"A new paper that was just published in PRL casts doubt on the idea that the universe went through a big bounce, rather than starting with a big bang.

"Physicists have many ideas for the beginning of our universe. The simplest one is a Big Bang where the energy density in the universe was incredibly high. The Big Bang did not happen at a particular point but everywhere. If you find that confusing, you’re not the only one, and you’ll be happy to hear that I made a video about this in particular.

"The second most popular idea is that, yes, the universe had this phase of high energy density, but it wasn’t the beginning. Rather, it was itself the end of a previous phase in which the universe contracted. This is called a “Big Bounce”. There are several of these Big Bounce models. The best known one is probably Penrose’s Cosmic Cyclic Cosmology, which you can learn about in my previous video.

"However, it isn’t the best-studied one because it’s kind of difficult to figure out how to use Penrose’s model, I speak from my own experience. The most studied bounce model is probably that of Loop Quantum Cosmology . It’s based on the idea of Loop Quantum Gravity, the main competitor of string theory.

***

"In the new paper they now say that if you have a bounce model which does that, it would also have another property, which is to induce new correlations in the CMB. They’re known as the bi-spectrum or three-point correlations. I know this sounds somewhat intimidating but don’t worry, only thing you need to know is that these correlations don’t seem to be there.

"The authors now say you can’t have your cake and eat it too. Either you have a bounce model that explains the large scale CMB properties, but then it screws up the bi-spectrum. Or it agrees with the bi-spectrum, but then it doesn’t help with the large scales.

"This doesn’t rule out bounce models. To begin with it’s only a particular type of bounce models that they looked at. It does take away one of their appeals, but there’s still the appeal that you can make them more complicated and continue writing papers about them. (my bold)

Comment: My bold illustrates the problem, which is 'anything but God'. The big Bang can include God, but a bouncing universe is eternal, no God needed. 99% of the evidence favors the Big Bang.

1335 views

May relate to our black hole:

https://www.newscientist.com/article/2376644-hundreds-of-weird-filaments-of-gas-are-hid...

"The centre of our galaxy is full of hundreds of strange threads of hot gas, which may have formed due to an outburst from Sagittarius A*, the Milky Way’s resident supermassive black hole.

"Farhad Yusef-Zadeh at Northwestern University in Illinois and his colleagues found these filaments using data from the MeerKAT radio telescope in South Africa. In the 1980s, Yusef-Zadeh discovered a set of vertical filaments aligned perpendicular to the disc of the galaxy, but the newfound horizontal filaments were completely unexpected.

“'The vertical filaments are aligned with the galaxy’s magnetic field, but the rest should be randomly aligned,” he says. “The pattern that I saw caught me by surprise – at first, I didn’t believe it."

"While the vertical filaments measured up to 150 light years tall, the horizontal ones are only 5 to 10 light years long, all pointing towards Sagittarius A*. These horizontal filaments seem to be made of gas, unlike the vertical filaments, which are most likely made up of high-energy electrons. They also seem to be moving away from Sagittarius A*, towards the outer areas of the galaxy where Earth sits.

"While the vertical filaments measured up to 150 light years tall, the horizontal ones are only 5 to 10 light years long, all pointing towards Sagittarius A*. These horizontal filaments seem to be made of gas, unlike the vertical filaments, which are most likely made up of high-energy electrons. They also seem to be moving away from Sagittarius A*, towards the outer areas of the galaxy where Earth sits.

"There have been some hints from studies of the area right next to Sagittarius A* that such an outburst occurred, but they have not been confirmed yet. “We really want to piece together these larger-scale structures with the smaller scale around the black hole and show that there really is this jet coming out along the disc of the galaxy,” says Yusef-Zadeh. “That could have really profound implications on our understanding of the spin axis of the black hole.”

"It could mean that Sagittarius A*’s spin axis is perpendicular to that of the galaxy as a whole, which would be an important clue as to how our galaxy formed and how it interacts with its central black hole now."

Comment: still lots to learn about the Milky Way. Since it contains our Earth with its life, I would assume it is carefully favored by God and everything is there for a purpose of protecting the Earth from untoward events.

1318 views

Compared to all other systems we see:

https://www.scientificamerican.com/article/we-live-in-the-rarest-type-of-planetary-system/

"Scientists had long thought our own solar system—an “ordered” arrangement of tiny orbs closer to the sun and big ones farther out—was a typical outcome of this complex process. But NASA's planet-hunting Kepler mission revealed that most systems don't resemble our own at all, instead having “similar” configurations of closely packed worlds all nearly the same size and mass, like peas in a pod.

"This disparity inspired astrophysicists Lokesh Mishra, now at IBM, Yann Alibert of the University of Bern and their colleagues to investigate what other architectures might exist. This is a formidable task for modern telescopes but a question that computer models can easily explore. Through their research they noted a third system type in the observational data—a “mixed” distribution of shuffled small and large planets—and their simulations predicted one more: an “antiordered” architecture of worlds that get smaller and less massive the farther they are from their star. These findings, which appear in two studies in Astronomy & Astrophysics, reinforce the conclusion that similar architectures are most common and suggest that ordered systems like our own are the rarest.

***

"Crucially, this research introduces a new mathematical framework for quantifying similarities among a system's planets according to any observable characteristic, such as mass or size; one number reveals the total range of values for that characteristic among the planets, and the other reflects how widely those values typically vary from planet to planet. This can help uncover patterns that reveal broad rules governing the birth and growth of planetary systems—as well as where those orderly rules break down. Matching their model's predictions to observations suggests, for instance, that similar systems' pea-pod planets emerge from sedate, low-mass protoplanetary disks, with higher-mass disks more easily making big planets—like our own system's Jupiter—that can chaotically interact to yield the three other architectures. The powerful James Webb Space Telescope and other facilities may soon be able to test some of these ideas.

"University of Chicago astrophysicist Daniel Fabrycky, who was not involved with the new research, says such upcoming observations make these kinds of studies especially valuable. “This is about building some set of concepts, around which we expect to be able to make interesting conclusions in the future,” he says. “And that's always a good idea because it's more scientifically robust to make predictions and then check them, rather than observing surprising things and painting on a theoretical gloss afterward.'”

Comment: we have always thought of our planet as very special. (See privileged planet series) Now we find whole planetary arrangement is oddball. I see God's guiding hand here.

1310 views

Ethan Siegel discusses:

https://bigthink.com/starts-with-a-bang/heavy-hydrogen-dark-universe/?utm_campaign=swab...

"The 20th century brought with it the realization that the majority of what we know and experience in this physical Universe — atoms, light, and the known subatomic particles along with everything they combine to form — makes up only 5% of the total amount of stuff in the Universe. The remaining 95% is a mixture of things that are completely “dark” to us: dark matter, which gravitates, and dark energy, which drives the expanding Universe ever farther apart.

***

"They indicate, combined, that our Universe is only 5% normal matter, with 27% being dark matter and 68% being dark energy. While it’s easy to attempt to poke holes in this consensus cosmology picture, it’s been incredibly resilient.

"Remarkably, there’s an easy and straightforward way to show that only ~5% of the Universe, total, can be made of normal matter: by looking at hydrogen and its rare, heavy isotope, deuterium. Here’s how measuring this “heavy hydrogen” reveals the existence of the dark Universe.

***

" Given the Standard Model of particle physics, and how nuclear processes are known to work, there should be a particular ratio of the light elements that survive today that depends on one property of the Universe alone: the ratio of baryons (protons and neutrons combined) to photons.

"This is such a powerful technique because the number density of photons from the Big Bang is so precisely known: it’s been measured to be 411 photons per cubic centimeter at present, and so long as we understand how the Universe has expanded over its lifetime, we can infer just how many photons were present in a given volume of space at any point in the cosmic past.

***

"In a Universe without pristine stars, how could you possibly try and reconstruct how much deuterium was present immediately following the Big Bang?

"One method you might consider is to measure the ratios of elements in a variety of stellar populations. If you measure, say, the oxygen-to-hydrogen or iron-to-hydrogen ratios, and also measure the deuterium-to-hydrogen ratio, you could graph them together, and use that information to extrapolate backward: to a zero oxygen or iron abundance. This is a pretty solid method, and gives us an estimate for how much deuterium would be present at a time before heavy elements, like oxygen or iron, had formed.

***

"By looking at the best quasar data we have in the Universe, and finding the closest-to-unpolluted molecular clouds that exist along their lines-of-sight, we can reconstruct the primordial deuterium abundance to extreme precision. The latest results tell us that the amount of deuterium in the Universe, by mass, was 0.00253% of the initial hydrogen abundance, with an uncertainty of only ±0.00004%.

"This corresponds to a Universe that’s made up of about 4.9% normal matter: consistent to within ~0.1% of the value inferred from the imperfections in the cosmic microwave background radiation, but in an entirely independent way.

***

"In November of 2020, at an underground laboratory in Italy, a plasma physics experiment published a paper detailing what they saw when they went and recreated the high temperatures and densities that were present during the hot Big Bang. They observed the reactions between deuterium and protons directly in their experiment, which ran from 2017-2020. It took three years to measure enough different conditions to high-enough precisions to recreate the necessary temperature ranges, but when all was said and done, they had the best measurement of this particular reaction rate ever: with an uncertainty of just 1.6%.

"Most importantly, though, it confirmed our expectations. Although the uncertainties had been larger, previously, the central value didn’t shift by very much at all, meaning that our estimates for how the deuterium abundance corresponds to and translates into an overall matter density was actually extremely good. The Universe, as best as we can tell, really is made of about 5% normal matter, and can’t be more than that. Even if we don’t know what dark matter’s nature is, this experiment shows us that practically none of it is allowed to be “normal matter that, for some reason, is just dark.”

***

"That’s why we demand multiple, independent lines of evidence for a conclusion before we confidently accept it. The science of Big Bang Nucleosynthesis is one of those incredibly important cross-checks. It’s an independent test not only of the Big Bang model of the early Universe, but of our concordance cosmological model. It tells us, all on its own, what the total amount of normal matter in the Universe is. Since the other lines of evidence, like colliding galaxy clusters or the large-scale structure of the Universe, require far more matter than the deuterium (or heavy hydrogen) abundance tells us can exist, we can be much more confident that dark matter is real. From the latest observations and experiments, only 4.7-5.0% of the entire energy budget of the Universe can be composed of normal matter. The remaining 95%, whatever it is, must truly be dark."

Comment: Siegel presents clear proof. Which tells me life can only appear in lighted areas. Why all the dark is needed is an unsolved mystery.

1320 views

A new approach to an expanding universe:

https://www.livescience.com/physics-mathematics/dark-energy/the-expansion-of-the-univer...

"The expansion of the universe could be a mirage, a potentially controversial new study suggests. This rethinking of the cosmos also suggests solutions for the puzzles of dark energy and dark matter, which scientists believe account for around 95% of the universe's total energy and matter but remain shrouded in mystery.

***

"Scientists know the universe is expanding because of redshift, the stretching of light's wavelength towards the redder end of the spectrum as the object emitting it moves away from us. Distant galaxies have a higher redshift than those nearer to us, suggesting those galaxies are moving ever further from Earth.

"More recently, scientists have found evidence that the universe's expansion isn't fixed, but is actually accelerating faster and faster. This accelerating expansion is captured by a term known as the cosmological constant, or lambda.

"The cosmological constant has been a headache for cosmologists because predictions of its value made by particle physics differ from actual observations by 120 orders of magnitude. The cosmological constant has therefore been described as "the worst prediction in the history of physics."

***

"'In this work, we put on a new pair of glasses to look at the cosmos and its unsolved puzzles by performing a mathematical transformation of the physical laws that govern it," Lombriser told Live Science via email.

"In Lombriser's mathematical interpretation, the universe isn't expanding but is flat and static, as Einstein once believed. The effects we observe that point to expansion are instead explained by the evolution of the masses of particles — such as protons and electrons — over time.

"In this picture, these particles arise from a field that permeates space-time. The cosmological constant is set by the field's mass and because this field fluctuates, the masses of the particles it gives birth to also fluctuate. The cosmological constant still varies with time, but in this model that variation is due to changing particle mass over time, not the expansion of the universe.

"In the model, these field fluctuations result in larger redshifts for distant galaxy clusters than traditional cosmological models predict. And so, the cosmological constant remains true to the model's predictions.

"I was surprised that the cosmological constant problem simply seems to disappear in this new perspective on the cosmos," Lombriser said.

"Lombriser's new framework also tackles some of cosmology's other pressing problems, including the nature of dark matter. This invisible material outnumbers ordinary matter particles by a ratio of 5 to 1, but remains mysterious because it doesn't interact with light.

"Lombriser suggested that fluctuations in the field could also behave like a so-called axion field, with axions being hypothetical particles that are one of the suggested candidates for dark matter.

"These fluctuations could also do away with dark energy, the hypothetical force stretching the fabric of space and thus driving galaxies apart faster and faster. In this model, the effect of dark energy, according to Lombriser, would be explained by particle masses taking a different evolutionary path at later times in the universe.

"In this picture "there is, in principle, no need for dark energy," Lombriser added.

***

"The paper is pretty interesting, and it provides an unusual outcome for multiple problems in cosmology," García, who was not involved in the research, told Live Science. "The theory provides an outlet for the current tensions in cosmology."

"However, García urged caution in assessing the paper's findings, saying it contains elements in its theoretical model that likely can't be tested observationally, at least in the near future."

Comment: the result of the study is to invent unknown particles in fields that give you a desired result. This method has predicted real particles in the past at more basic levels of the standard model. The final comments are a key to how to view this, a tailoring of possibilities to solve problems. It leaves us at a neat trick or does it point to something that may exist?

1278 views

No idea why?:

https://www.newscientist.com/article/2379105-centre-of-our-galaxy-has-a-zone-of-avoidan...

"There is a strange and unexplained “zone of avoidance” for stars near the centre of the Milky Way. Stars at any given distance from the supermassive black hole at the galactic centre, called Sagittarius A*, should have a random distribution of shapes to their orbits, but one group of stars is mysteriously missing from that distribution.

"The group of about 200 stars that reside near Sagittarius A* are called S-stars, and their very existence is somewhat unexpected because the environment in that area is extremely hostile. Andreas Burkert at University Observatory Munich in Germany and his colleagues examined the orbits of the 50 or so of these stars for which we have solid data to search for patterns.

"They found a close correlation between each star’s distance from the galactic centre and the shape of its orbit – the closer a star is to the middle of the galaxy, the more stretched out, or eccentric, its orbit is. Unexpectedly, in the area immediately around Sagittarius A*, there are no stars with circular orbits, a phenomenon the researchers call a zone of avoidance. If those stars existed, they would be the easiest to spot, so it is unlikely that this strange zone comes from a problem with the data itself.

“'The zone of avoidance has a very sharp upper boundary,” says Burkert. “It’s as if something forbids stars from going into the zone, or the ones that do go into the zone get destroyed.” But given that there are plenty of stars close to Sagittarius A*, there is no known reason there shouldn’t be any within the zone of avoidance.

“'It seems that the presence of a supermassive black hole creates an underlying mechanism that forces objects to arrange in a non-randomised pattern,” says Florian Peissker at the University of Cologne in Germany. “The big and important question is: why is that?” Figuring it out will be crucial to our understanding of how black holes shape their environments, not just in their immediate surroundings but further out as well, he says.

"There are two main hypotheses to explain the shapes of the S-stars’ orbits and how they can be so close to Sagittarius A*. The first is that there could be another, smaller black hole in the same area changing the stars’ orbits, and the second is that the S-stars used to be binaries, but one of the pair was flung away into deep space and the other remained in a tight orbit at the centre of the galaxy.

"Neither of these ideas can explain the zone of avoidance and the other, more subtle patterns the researchers spotted. “These are the competing theories, and they don’t have to compete anymore because they don’t work,” says Burkert. “We don’t really know what it is yet. I think that’s the most exciting part.'”

Comment: just goes to show we have lots to learn about our home galaxy.

1291 views

Latest research:

https://www.science.org/content/article/long-sought-hum-of-gravitational-waves-from-gia...

"By turning networks of dead stars into galaxy-size gravitational wave detectors, radio astronomers have tuned into the slowly undulating swells in spacetime thought to arise from pairs of supermassive black holes (SMBHs) that are about to collide.

"In a simultaneous announcement today, five separate international teams said that after nearly 20 years of effort they had found evidence for these gravitational waves. They are far longer than the waves first captured by ground-based detectors in 2015, which emanate from collisions of star-size objects. The findings not only open up a new window in gravitational wave astronomy, but will also help researchers answer questions about the origin and evolution of SMBHs, objects that sit at the center of galaxies and weigh as much as billions of Suns. The results could even uncover hints of new physics.

"The new results rely on millisecond pulsars, highly magnetized stellar remnants that emit beams of radiation as they spin as fast as 1000 times per second. Their lighthouse-like radio signals sweep past our planet with a regularity that rivals an atomic clock. Should a passing gravitational wave intrude anywhere along the path between Earth and the pulsar, it will stretch and squash the fabric of space—and cause small variations in the timing of the flashes. “Those ultraprecise signals will arrive a little bit early, and then a little bit late,” says Chiara Mingarelli, an astrophysicist at Yale University and a member of the North American Nanohertz Observatory for Gravitational Waves. NANOGrav is one of the five international pulsar timing arrays (PTAs), which draw on data from a dozen radio telescopes around the world to monitor dozens of the beacons for evidence of the waves.

***

"The background signal is stronger than expected, implying that this population of imminently merging SMBHs numbers in the hundreds of thousands, perhaps even millions. It could also mean the SMBHs are either bigger or merging more quickly than astronomers previously predicted—a possibility consistent with observations from NASA’s JWST space telescope hinting that galaxies grew larger and faster in the early universe than once thought.

***

"Having heard the cosmic hum, the teams now want to listen more closely, digging deeper into their data sets to find out what else they might learn. “We’re not even close to the end of the story,” Hessels says. “It’s a game of dedication and patience.'”

Comment: it takes dedication, perseverance, and money to reach this type of result. All because we are so curious. One day we may be able to tell dhw why the universe is so big.

1236 views

A new discovery:

https://www.sciencenews.org/article/neutrinos-new-view-milky-way-space

"Scientists have made the first image of the Milky Way using neutrinos.

"The extremely low-mass subatomic particles have no electric charge, and pass easily through gas, dust and even stars on their way from the places where they originate to detectors here on Earth. High-energy neutrinos zip throughout the cosmos, but where they come from is usually a mystery.

"Now, by combining artificial intelligence and data collected over the course of a decade with the IceCube detector in Antarctica, researchers have found the first evidence of high-energy neutrinos that originated from inside the Milky Way and mapped the particles onto an image of the galaxy’s plane. It’s the first time our galaxy has been imaged with anything other than light.

"The map includes suggestions of specific high-energy neutrino sources within the Milky Way that might be the remnants of past supernova star explosions, the cores of collapsed supergiant stars or other as-yet-unidentified objects, the team reports in the June 30 Science. But more research is needed to clearly pick those sorts of features out of the data.

"Previously, only a few high-energy neutrinos have been traced back to their potential birthplaces, all outside the Milky Way. Those include two that appeared to come from black holes shredding their companion stars and others from a highly active galaxy known as a blazar.

***

"Neutrino astronomy could potentially allow us to see distant objects in a way that no other telescopes can match. That’s because neutrinos can cross huge expanses of space without being absorbed or deflected. X-rays, gamma rays, optical light and the charged particles that make up cosmic rays, on the other hand, can be deflected or absorbed along the way, which may obscure their origins.

***

"The downside of neutrinos is that they’re extremely hard to detect. The IceCube experiment is enormous in part to overcome that challenge. It consists of 5,160 sensors in a cubic array one kilometer on a side embedded deep in the Antarctic ice. The large size of the experiment increases the odds of seeing a tiny fraction of the neutrinos flying through space from the Milky Way and other places in the cosmos.

"Of the 100,000 or so neutrinos that IceCube scientists observe each year, some leave long tracks in the detector that potentially point back to where the neutrinos came from. Many of the neutrino signals in IceCube, though, are known as cascade events. They make bursts of light in the detector, but don’t reveal neutrino origins as well as tracks can.

“'This is data we used to throw away in terms of astronomy,” Kurahashi Neilson says. There’s still information indicating where the neutrinos come from in the data. But it’s difficult to identify the promising cascades in the hundreds of thousands of meaningless, background events that IceCube has collected."

Comment: paradoxically, this massless particle may help to explain why the universe is so big, a crushing worry from dhw.

1194 views

Only like eleven percent of others:

https://www.sciencealert.com/what-does-our-galaxy-look-like-to-alien-astronomers?utm_so...

"What does the Milky Way's chemistry look like from millions of light years away?

Research led by the Max Planck Institute for Astronomy in Germany and Yunnan University in China has provided an answer: Our galaxy is an oddball, though not one-of-a-kind.

"The Milky Way sticks out among other similarly sized galaxies with metal concentrations that are very low at the center, rise towards the halfway point, and then peter out on the outskirts of the galaxy.

"By comparison, the metal distribution of other galaxies is much flatter, more like a pancake than a doughnut.

"Our galaxy "is not unique but is not common", the researchers report. "The Milky Way might not have a typical metallicity distribution for a galaxy of its mass."

"Astronomers use the word 'metal' to refer to all elements that are heavier than hydrogen and helium.

"Hydrogen and helium nuclei formed around three minutes after the Big Bang, with electrons hitching a ride around 380,000 years later to make atoms. Heavier elements are the product of billions of years of stellar evolution, requiring more time to emerge.

"For this reason, stars that were born earlier in the history of the Universe tend to have fewer metals than those born later.

"The researchers compared our Milky Way to 321 galaxies of similar masses observed as part of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey.

"They found that only one percent of these galaxies matched the Milky Way in terms of metal distribution.

"The researchers also compared the Milky Way with 134 galaxies created in the TNG50 simulation of the Universe, which modeled the evolution of tens of thousands of galaxies over a 13.8-billion-year period.

"Only 11 percent of the simulated galaxies were like ours.

"Why is our Milky Way so strange?

"There are a few explanations. Perhaps the older stars with lower metal content used up all the resources at the center of the galaxy. This would mean that few young stars were born there, which would explain the dip in metals at the center.

"Alternatively, the supermassive black hole at the center of the Milky Way may have spewed out radiation as it ate, making star formation in the center difficult.

"The scarcity of metals at the edges of the Milky Way could be caused by our galaxy swallowing another galaxy with low metal content.

"Another possibility is that the estimated size of the Milky Way's disk of stars was wrong, which might be addressed in upcoming surveys such as the WHT Enhanced Area Velocity Explorer (WEAVE) and the Sloan Digital Sky Survey V (SDSS-V), say the researchers.
'
"Finding ways to compare our home galaxy with more distant galaxies is what we need if we want to know whether the Milky Way is special or not," says lead author and astronomer Jianhui Lian."

Comment: a special Earth in a special galaxy and we are here. Not surprising.

1182 views

A new approach for measurement:

https://phys.org/news/2023-06-astrophysicists-cosmic-expansion-lensed-gravitational.html

"The universe is expanding; we've had evidence of that for about a century. But just how quickly celestial objects are receding from each other is still up for debate.

"It's no small feat to measure the rate at which objects move away from each other across vast distances. Since the discovery of cosmic expansion, its rate has been measured and re-measured with increasing precision, with some of the latest values ranging from 67.4 up to 76.5 kilometers per second per megaparsec, which relates the recession velocity (in kilometers per second) to the distance (in megaparsecs).

"The discrepancy between different measurements of cosmic expansion is called the "Hubble tension."

***

"Measurements of the cosmic expansion rate boil down to velocity and distance. Astronomers use two kinds of methods to measure distances: the first start with objects with a known length ("standard rulers") and look at how big they appear in the sky. These "objects" are features in cosmic background radiation, or in the distribution of galaxies in the universe.

"A second class of methods starts with objects of known luminosity ("standard candles") and measures their distances from Earth using their apparent brightness. These distances are connected to those of farther bright objects and so on, which builds up a chain of measurement schemes that is often called the "cosmic distance ladder." Incidentally, gravitational waves themselves can also help measure cosmic expansion, since the energy released by the collision of neutron stars or black holes can be used to estimate the distance to these objects.

"The method that Nerella and his co-authors propose belongs to the second class but uses gravitational lensing. This is a phenomenon that occurs when massive objects warp spacetime, and bend waves of all kinds that travel near the objects. In rare cases, lensing can produce multiple copies of the same gravitational wave signal that reach Earth at different times—the delays between the signals for a population of multiple imaged events can be used to calculate the universe's expansion rate, according to the researchers.

"'We understand very well just how sensitive gravitational wave detectors are, and there are no astrophysical sources of confusion, so we can properly account for what gets into our catalog of events," Nerella said. "The new method has sources of error that are complementary to those of existing methods, which makes it a good discriminator."

"The sources of these signals would be binary black holes: systems of two black holes that orbit each other and ultimately merge, releasing massive amounts of energy in the form of gravitational waves. We haven't yet detected strongly lensed examples of these signals, but the upcoming generation of ground-based detectors is expected to have the necessary level of sensitivity.

***

"According to lead author Souvik Jana, unlike other methods of measurement, this method does not rely on knowing the exact locations of, or the distances to, these binary black holes. The only requirement is to accurately identify a sufficiently large number of these lensed signals. The researchers add that observations of lensed gravitational waves can even provide clues on other cosmological questions, such as the nature of the invisible dark matter that makes up much of the energy content of the universe."

Comment: perhaps we will have one solid number for the Hubble constant.

1203 views

From one billion years after the Big Bang:

https://www.sciencealert.com/stars-from-the-dawn-of-the-universe-found-hidden-in-the-he...

"Ancient stars born during the Cosmic Dawn have been identified in the center of the Milky Way.

"As part of a survey to uncover some of the oldest known stars in the Universe, scientists conducted a comprehensive search for these ancient, but elusive, stars, and found that the measures they spin around the galactic center are relatively sedate, in spite of the chaos around them.

***

"We can tell how old a star is based on how much metal is in it. When the first stars in the Universe formed, they had to make themselves out of the elemental material available at the time – mostly hydrogen and helium. But the nuclear furnaces burning in their cores started fusing the atoms of hydrogen into heavier things, from helium all the way up to iron.

"Then, when they exploded in messy supernovae, they seeded these heavier elements throughout space, along with even heavier elements forged in energetic split-second supernova processes. Subsequent stars therefore started their lives with a greater proportion of heavier material. The younger a star is, the more metal it's likely to have.

***

"Astronomers think that the oldest of the old stars should be hanging out in the galactic center, but because the region is predominantly rich in metal, and there's a lot of dust blocking our view, they tend to be harder to find.

"Anke and her colleagues embarked on a project called the Pristine Inner Galaxy Survey (PIGS) to try and find them. By analyzing the spectrum of light emanating from a certain star, astronomers can find wavelengths amplified or dampened by the presence of certain elements. They looked for an elemental signature consistent with stars that are very low in metals, and identified around 8,000 candidates.

***

"They used data from the Gaia observatory, which is an ongoing project to map the three-dimensional positions and motions of the stars in the Milky Way. With this, the researchers were able to determine the galactic orbits of their old stars.

"Arentsen and her colleagues found that orbits of the ancient stars around the galactic center are relatively slow.

"In addition, the older stars have more chaotic orbits, but they still have an average orbit around the galactic center.

"Finally, the orbits of the stars are mostly contained entirely within the galactic center. Even those stars on elliptical orbits tend to stay mostly within the central region of the Milky Way.

"'It is exciting to think that we are seeing stars that formed in the earliest phases of the Milky Way, previously largely out of reach. These stars likely formed less than a billion years after the Big Bang, so are relics from the early Universe," Arentsen says.'

Comment: just as I see our planet as privileged, I view our galaxy the same way, and I see this finding as an example of God directing traffic to designing our galaxy to be perfect for us.

1149 views

Stripped giants:

https://phys.org/news/2023-07-supergiant-reveals-evolutionary-stage.html

"Dr. Varsha Ramachandran from the Center for Astronomy of Heidelberg University (ZAH) and her colleagues uncovered the first "stripped" star of intermediate-mass. This discovery marks a missing link in our picture of stellar evolution toward systems with merging neutron stars, which are crucial to our understanding of the origin of heavy elements, such as silver and gold.

***

"The team of researchers discovered the first representative of the long-predicted, but as yet unconfirmed population of intermediate-mass stripped stars. "Stripped stars" are stars that have lost most of their outer layers, revealing their hot and dense helium-rich core, which results from the nuclear fusion of hydrogen to helium. Most of these stripped stars are formed in binary star systems in which one star's strong gravitational pull peels off and accretes matter from its companion.

"For a long time, astrophysicists have known of low-mass stripped stars, known as subdwarfs, as well as their massive cousins, known as Wolf-Rayet stars. But until now, they have never been able to find any of the so-called "intermediate-mass stripped stars," raising questions whether our basic theoretical picture needs a major revision.

"By surveying hot and luminous stars with high-resolution spectroscopy devices of the VLT, the Very Large Telescope of the European Southern Observatory in Chile, Dr. Ramachandran and her colleagues detected suspicious signatures in the spectrum of a hot, massive star that previously had been classified as a single object. A detailed investigation of the spectrum revealed that the object is not a single star but actually a binary system, consisting of the intermediate-mass stripped star and a fast rotating companion, a so-called Be star that had been spun-up by accreting mass from the stripped-star progenitor.

***

"'With our discovery, we demonstrate that the long-missing population of such stars is actually there. But our findings also indicate that they might look very different from what we had expected," Dr. Ramachandran explains and adds that instead of having completely lost their outer layers, such stars may retain a small but sufficient amount of hydrogen on top of their helium cores, which makes them appear much bigger and cooler than they really are.

"'We thus call them 'partially stripped stars,'" she adds. Dr. Andreas Sander points out that their mantle of remaining hydrogen is a form of disguise. "Partially stripped stars appear very similar to normal, non-stripped hot stars, thereby essentially hiding in plain sight. Only high-resolution data combined with careful spectral analysis and detailed computer models can reveal their true nature."

"It is no surprise they have evaded detection for so long. "The particular giveaway of this star was its mass: a few times more massive than our sun may seem like a lot, but that is extraordinarily light for its blue supergiant appearance," the research group leader explains.

***

"'Our stellar evolution models predict that in about a million years from now, the stripped star will explode as a so-called stripped-envelope supernova, leaving behind a neutron star remnant," Dr. Klencki says.

"The discovery by Dr. Ramachandran and her colleagues marks the first such stripped star found to date in a metal-poor galaxy. If the binary survives the supernova explosion, the roles of the two stars will reverse: Then, the Be-star companion will donate mass to the neutron star accretor, becoming a so-called Be X-ray binary.

"Such fascinating systems are considered to be the progenitors of double neutron star merger events, perhaps the greatest cosmic spectacles observed to date and the origin of chemical elements like silver or gold. Understanding their formation path is one of the main challenges of modern astrophysics, and observations of intermediate evolutionary stages are crucial to achieve this.

"'Our discovery adds a major piece to the puzzle, yielding the first direct constraints on how mass transfer evolution proceeds in such massive star systems," Dr. Ramachandran concludes.'

Comment: when a star blows, it spreads all the elements we need to use. Each discovery shows us its purposeful reason for existing. I would assure dhw, all his doubts about the massive universe have reasons.
Comment:

1138 views

Not fully understood:

https://knowablemagazine.org/article/physical-world/2023/probing-mysteries-neutron-star...

"Ever since neutron stars were discovered, researchers have been using their unusual properties to probe our universe. The superdense remnants of stellar explosions, neutron stars pack a mass greater than the Sun’s into a ball about as wide as San Francisco. A single cup of this star matter would weigh about as much as Mount Everest.

***

"Stars power themselves by fusing the nuclei of lighter atoms into those of heavier atoms. But when stars run out of those lighter atoms, nuclear fusion stops and there is no longer an outward pressure to fight against the inward force of gravity. The core collapses and the star’s outer layer races inward. When this layer hits the dense core, it bounces off and explodes outward, producing a supernova. The dense core that remains afterward is a neutron star.

***

"As some of the densest, highest-pressure objects in the universe, neutron stars might help us learn about what happens to matter at extremely high densities. Understanding their structure and the behavior of the neutron matter composing them is of paramount importance to physicists.

***

"Matter that is below its Fermi temperature can obey remarkably universal laws. This universality means that, while we don’t have easy access to several-million-degree neutron star matter, we could learn about some of its behavior by experimenting with ultracold gases that can be created and manipulated in laboratory vacuum chambers on Earth, says theoretical astrophysicist James Lattimer of Stony Brook University in New York.

***

"These ultracold atom clouds are actually closer to being a unitary gas than neutron star matter, so the analogy isn’t perfect. But it’s close enough that Lattimer has been able to take almost-unitary-gas measurements from the cold-atom clouds and apply them to neutron matter to refine some of the theoretical models that describe the internal workings of neutron stars. And experiments with cold atoms can help scientists develop theories about what physics might be at play in some unexplained neutron star phenomena.

***

"In particular, Graber and other scientists are hoping to find clues to one of the biggest mysteries, called pulsar glitches. Generally, the regularly timed ticking of a pulsar “clock” is so reliable that its accuracy rivals that of atomic clocks. But not always: Sometimes, the pulsar’s rate of rotation increases abruptly, causing a glitch. Where that extra oomph comes from is unclear. The answer lies with how that matter moves around inside a neutron star.

***

"Researchers are busy examining how other ultracold phenomena they regularly see in the lab can inspire new lines of research into the behavior of neutron stars. Recently, Graber and her colleagues outlined so many possibilities that they needed 125 pages to publish them all. In 2019, dozens of astronomers, nuclear physicists and ultracold atomic physicists from around the world gathered to discuss more of the surprising connections between their fields. Researchers are just beginning to test some of the ideas generated by these brainstorms.

"They’re also learning more from the stars themselves, says Pethick. “It’s an exciting field, because at the moment there are a lot of observations coming in.”

"With better telescopes and new methods to glean properties about a neutron star’s inscrutable interior, scientists can hope to find out just how far this analogy between cold atoms and neutron stars can be taken."

Comment: so astronomy becomes a big dance, analyzing what we can see and measure out there and doing mimicking experiments in the lab. My view is all of this exotic stuff exists so it must be required.

1145 views

Our expanding universe:

https://bigthink.com/starts-with-a-bang/space-big-place/?utm_campaign=swab&utm_sour...

"There are few things we can conceive of that are as mind-bogglingly large as space is. Our observable Universe, out to the deepest recesses of space that we can possibly see, takes us out some 46 billion light-years in all directions. From the Big Bang until now, our Universe has expanded while gravitating at the same time, giving rise to stars and galaxies spread across the expanse of outer space. All told, there are currently several trillion galaxies present within it, as for every galaxy we know about, there are perhaps 30 to 100 that are too small, faint, and distant for us to presently observe.

"And yet, if we go back in time, we learn that not only was our Universe a much smaller place, but that in the earliest stages, the Universe itself was anything but impressive. If the Universe has been expanding and cooling for 13.8 billion years, then long ago, it must have been smaller and denser, implying that there may not always have been such a remarkably large volume to contain all the particles that have existed for so long. Space may not always have been a big place, and it’s only the fact that our Universe has expanded so thoroughly and relentlessly that made it so big and empty today.

***

"if we went back to a time when a mere one second had passed since the Big Bang, back when the last of the early Universe’s antimatter (in the form of positrons) was annihilating away, the entire observable Universe would only be about 100 light-years in diameter.

"And it means that in the very early stages of the Universe, back when only perhaps a picosecond (10-12 seconds) had passed since the Big Bang, the entire observable Universe could fit inside a sphere no bigger than the size of Earth’s orbit around the Sun. The entire observable Universe, back in the Big Bang’s early stages, was smaller than the size of our Solar System.

"You might think that you could take the Universe all the way back to a singularity: to a point of infinite temperature and density, where all its mass and energy concentrated into a singularity. But we know that’s not an accurate description of our Universe. Instead, a period of cosmic inflation must have preceded and set up the Big Bang.

"From evidence in today’s Cosmic Microwave Background, we can conclude there must have been a maximum temperature that the Universe reached during the hot Big Bang: no more than about ~1029 K. Although that number is enormous, it’s not only finite, it’s well below the Planck scale. When you work out the mathematics, you find a minimum diameter for the Universe at the start of the hot Big Bang: around 1 meter (3.3 feet), or around the size of a human child.

***

"It’s also true that we don’t know how long inflation endured for or what, if anything, came before it. But we do know that when the hot Big Bang began, all the matter and energy that we see in our visible Universe today, all the stuff that extends for 46.1 billion light-years in all directions, must have been concentrated into a volume of around the size of a soccer ball.

"For at least a short period of time, the vast expanse of space that we look out and observe today was anything but big. All the matter making up entire massive galaxies would have fit into a region of space smaller than a pencil eraser. And yet, through 13.8 billion years of expansion, cooling, and gravitation, we arrive at the vast Universe we occupy a tiny corner of today. Space may be the biggest thing we know of, but the size of our observable Universe is a recent achievement. Space wasn’t always so big, and the evidence is written on the face of the Universe: where all of us can see the evidence."

Comment: readers here know this story. What it tells us is that as life was evolved, so was the universe evolved. This tells us God prefers to evolve His creations for His own reasons. We have no idea why He wanted it to expand to such a big size, but I'm sure God had his unknown reasons.

1197 views

New possibility:

https://www.newscientist.com/article/2384429-we-may-have-finally-figured-out-how-galaxy...

"We may finally know how the magnetic fields that now permeate the universe first arose. Much of the universe was once a churning unmagnetised plasma, and a new set of simulations shows how that plasma may have developed powerful magnetic fields.

"Lorenzo Sironi at Columbia University in New York and his colleagues simulated turbulence in plasma to study a phenomenon called the Weibel instability. When a fluid is turbulent, asymmetries can develop when more particles happen to be moving in one direction than the others. These asymmetries in charged particles cause tiny magnetic fields to spontaneously arise.

"The researchers found that the Weibel instability creates a small “seed” magnetic field, which forces charged particles to bunch together. That clumping, along with the swirling plasma, drives an increase in magnetism. “The turbulence takes these magnetic field lines and twists them, stretches them, folds them and that effectively makes them stronger,” says Sironi. This could grow a tiny magnetic field to the galactic and even intergalactic scales we see now, they found.

"This is important because the beginnings of large-scale magnetic fields has been an open question among astronomers for a long time. Individual objects such as stars and planets can generate their own magnetic fields easily through internal processes, but galaxies and clusters, and even the spaces between galaxies, are also often full of magnetic fields, and the origins of those have been tougher to tease out.

“'This could possibly provide a mechanism as to the reason some of the most pristine regions in the universe have a nonzero magnetic field,” says Sironi. “This is a mechanism for magnetising the universe.” It isn’t the only possible mechanism, he says, but it is a promising one. Understanding these magnetic fields could also help astronomers figure out the properties of turbulent plasmas across the universe, which are extremely difficult to measure directly."

Comment: a very possible answer. But doesn't help dhw who want to know why God's universe is so big. God wanted it that way.

1131 views

Latest studies:

https://bigthink.com/starts-with-a-bang/missing-baryons-too-hot/?utm_campaign=swab&...

"The cosmic web that we see, the largest-scale structure in the entire Universe, is dominated by dark matter. On smaller scales, however, baryons can interact with one another and with photons, leading to stellar structure but also leading to the emission of energy that can be absorbed by other objects. Neither dark matter nor dark energy can accomplish that task; our Universe must possess a mix of dark matter, dark energy, and normal matter.

"Unlike what we see, our Universe is mostly non-luminous.

***

"...it’s only the luminous matter (i.e., stars) that is typically seen by our telescopes; most of the matter, including most of the normal matter and all of the dark matter, is non-luminous.

"To form galaxies, galaxy clusters, and the large-scale cosmic web, both normal and dark matter are required.

"Today, our Universe’s composition is:

"5% normal matter,
27% dark matter,
and 68% dark energy.

"But much of the normal matter remains elusive. Galaxies contain stars, planets, gas, dust, and black holes, but not enough. The intergalactic medium, rich in ionized plasma, helps, but insufficiently so. Where’s the rest of the Universe’s normal matter? X-ray astronomy suggests a solution to this “missing baryons” problem: the circumgalactic medium.

"The “missing baryons” problem may be solved by the presence of a very hot, very sparse circumgalactic medium. This sparse, diffuse material surrounds every massive galaxy: ranging far beyond their stellar extents.

"With such low densities, very high temperatures are achieved. Its constituent atoms, as a result, lose most of their electrons. Several recent X-ray studies have detected this hot, ionized, galaxy-surrounding material. Light from distant sources must travel through the circumgalactic medium to reach us. Ionized atoms can absorb light at very specific frequencies. We see this for our Milky Way, including omnidirectionally, for many different extragalactic sources, and even around faraway galaxies. The hot, diffuse circumgalactic medium may finally solve our Universe’s “missing baryons” problem.

"Light from a distant galaxy shows key absorption lines from six-times ionized oxygen from its own circumstellar medium, providing strong evidence that the “missing baryons” around galaxies may actually be found in their circumgalactic mediums."

Comment: rich with informative illustrations. For full comprehension, see the website article.

1055 views

Finally unraveled:

https://www.livescience.com/space/cosmology/the-milky-way-wasnt-always-a-spiral-and-ast...

"A 100-year-old mystery surrounding the "shape-shifting" nature of some galaxies has been solved, revealing in the process that our Milky Way galaxy did not always possess its familiar spiral appearance.

"Astronomer Alister Graham used old and new observations to show how the evolution of galaxies from one shape to another takes place — a process known as galactic speciation . The research shows that clashes and subsequent mergers between galaxies are a form of "natural selection" that drives the process of cosmic evolution.

***

"Galaxies come in an array of shapes. Some, like the Milky Way, are composed of arms of well-ordered stars revolving in a spiral shape around a central concentration or "bulge" of stellar bodies. Other galaxies like Messier 87 (M87) are composed of an ellipse of billions of stars chaotically buzzing around a disordered central concentration.

"Since the 1920s, astronomers have classified galaxies based on a sequence of varying galaxy anatomy called the "Hubble sequence." Spiral galaxies like ours sit at one end of this sequence, while elliptical galaxies like M87 sit at the other. Bridging the gap between the two are elongated sphere-shaped galaxies, lacking spiral arms, called lenticular galaxies.

"But what this widely-used system has lacked until now were the evolutionary paths that link one galaxy shape to another.

***

"This [study] revealed the existence of two different types of bridging lenticular galaxies: One version that is old and lacks dust, and the other that is young and rich in dust.

***

"When dust-poor galaxies accrete gas, dust, and other matter, the disk that surrounds their central region is disrupted, with said disruption creating a spiral pattern radiating out from their hearts. This creates spiral arms, which are over-dense rotating regions that create gas clumps as they turn, triggering collapse and star formation.

"The dust-rich lenticular galaxies, on the other hand, are created when spiral galaxies collide and merge. This is indicated by the fact that spiral galaxies have a small central spheroid with extending spiral arms of stars, gas and dust. Young and dusty lenticular galaxies have notably more prominent spheroids and black holes than spiral galaxies and dust-poor lenticular galaxies.

"The surprising upshot of this is the conclusion that spiral galaxies like the Milky Way actually lie between dust-rich and dust-poor lenticular galaxies on the Hubble sequence.

***

"The history of the Milky Way is believed to be punctuated with a series of "cannibalistic" events in which it devoured smaller surrounding satellite galaxies to grow.

"This research indicates that in addition to this, our galaxy's cosmic "acquisitions" also included it accreting other material and gradually transforming from a dust-poor lenticular galaxy to the spiral galaxy we know today.

"Our galaxy is set for a dramatic merger with its closest large galactic neighbor, the Andromeda galaxy, in between 4 billion and 6 billion years. This collision and merger will see the spiral arm pattern of both galaxies erased and the new research indicates that the daughter galaxy created by this union is likely to be a dust-rich lenticular galaxy still possessing a disk, albeit without a spiral structure carved through it."

Comment: we live in a giant spiral galaxy safely halfway out the second spiral arm far from the very active center with its giant black hole. Not to worry about Andromeda colliding. Our sun will be dying at that point, and we won't survive the explosion, if we still exist. My view of God's role is monitoring the Milky Way's development placing the Earth properly for our safety.

949 views

The New Horizons Probe has helped in this discovery:

https://www.sciencealert.com/distant-objects-show-solar-system-extends-further-than-we-...

"Decades of peering into the shadows have left astronomers with the distinct impression that the diffuse field of icy boulders known as the Kuiper Belt suddenly thins out from 48 times the distance between Earth and the Sun (or 48 AU).

"Belts of rubble have been seen extending for at least twice that distance around comparable stars, making our Solar System rather petite by comparison. With this new discovery, we might not be so unusual after all.

"A team of astronomers led by Canada's Herzberg Astronomy and Astrophysics Research Centre had hoped to uncover new targets for the New Horizons Probe to investigate as it journeyed through the Solar System's outer reaches.

"Having given us a few close-ups of Pluto, the mission snapped pics of a snowman-shaped rock roughly 40 AU from the Sun, before continuing on its merry way at a speed of just under 60,000 kilometers (about 36,000 miles) per hour.

***

"...the research team made use of machine learning, training a neural network on made-up objects inserted into telescope imagery before setting it loose on data collected using the Subaru Telescope on Mauna Kea in Hawaii in 2020 and 2021.

"Compared with a human search through the 2020 data, the machine learning technique identified twice as many Kuiper Belt Objects, suggesting a distinct rise in the density of material at a distance of around 60 to 80 AU along New Horizons' trajectory.

***

'The study's results are yet to be peer-reviewed, and would then need to be confirmed by future ground- and space-based surveys.

"Yet taken at face value, it's possible our Solar System has at least two 'rings' of icy material divided by a gap at around 50 AU; one consisting of the familiar Kuiper Belt, the other a wide stretch of icy boulders reaching as far from Pluto as Pluto is from us."

Comment: not surprising there is a thin outer layer of rings.

682 views

Near our black hole is a hot spot:

https://www.sciencedaily.com/releases/2023/10/231010133549.htm

"An unexpectedly high number of young stars has been identified in the direct vicinity of a supermassive black hole and water ice has been detected at the center of our galaxy.

"An international team led by Dr Florian Peißker at the University of Cologne's Institute of Astrophysics has analysed in detail a young star cluster in the immediate vicinity of the super massive black hole Sagittarius A* (Sgr A*) in the centre of our galaxy and showed that it is significantly younger than expected. This cluster, known as IRS13, was discovered more than twenty years ago, but only now has it been possible to determine the cluster members in detail by combining a wide variety of data -- taken with various telescopes over a period of several decades. The stars are a few 100,000 years old and therefore extraordinarily young for stellar conditions. By comparison, our sun is about 5 billion years old. Due to the high-energy radiation as well as the tidal forces of the galaxy, it should in fact not be possible for such a large number of young stars to be in the direct vicinity of the super massive black hole.

***

"In connection with the current study, a further outstanding result has also been published. For the first time, the James Webb Space Telescope (JWST) was used to record a spectrum free of atmospheric interference from the Galactic Center. A prism on board the telescope was developed at the Institute of Astrophysics in the working group led by Professor Dr Andreas Eckart, a co-author of the publication. The present spectrum shows that there is water ice in the Galactic Center. This water ice, which is often found in the dusty discs around very young stellar objects, is another independent indicator of the young age of some stars near the black hole.

***

"'The analysis of IRS13 and the accompanying interpretation of the cluster is the first attempt to unravel a decade-old mystery about the unexpectedly young stars in the Galactic Center," according to Dr Peißker. "In addition to IRS13, there is a star cluster, the so-called S-cluster, which is even closer to the black hole and also consists of young stars. They are also significantly younger than would be possible according to accepted theories." The findings on IRS13 provide the opportunity in further research to establish a connection between the direct vicinity of the black hole and regions several light years away. Dr Michal Zajaček, second author of the study and scientist at Masaryk University in Brno (Czech Republic), added: "The star cluster IRS13 seems to be the key to unravelling the origin of the dense star population at the centre of our galaxy. We have gathered extensive evidence that very young stars within the range of the super massive black hole may have formed in star clusters such as IRS13. This is also the first time we have been able to identify star populations of different ages -- hot main sequence stars and young emerging stars -- in the cluster so close to the centre of the Milky Way.'"

Comment: this is an intimate finding that does not distinguish our galaxy from all others. Other galaxies are impossible for us explore at this level. However, we are learning more about our home galaxy all along.

659 views

That is how it grows:

https://www.universetoday.com/163632/the-milky-ways-stolen-globular-clusters/

"Modern astronomy holds that all major galaxies (with the Milky Way as no exception) are the accumulation of numerous small mergers. Thus, it should be expected that some of the globular clusters that are now part of our galaxy are likely inherited from other galaxies which have been cannibalized by the Milky Way, or even stolen from intact companion galaxies such as the Magellanic Clouds.

"Associations between these clusters and the various progenitors began in the 1990’s, but recent research is beginning to paint a more comprehensive picture on exactly what percentage of our globular clusters were stolen, and precisely which ones.

"The Milky Way is host to a large number of satellite galaxies. This includes the famous Magellanic clouds, but also includes less well known such as the Fornax Dwarf and the Antlia II Dwarf.

"But not all of these dwarf galaxies are so independent. Several, such as the Sagittarius Dwarf Galaxy, discovered in 1994, are notably elongated or distorted – more long streams of stars than organized galaxies. This suggests that they are currently being tidally torn apart and are in the process of merging into the Milky Way.

"Discoveries of these streams of tidally disrupted systems offered a potential solution for the puzzling observation: Many of the globular clusters surrounding our galaxy have a similar age, while others are relatively young. Astronomers began suggesting it was because these younger clusters were formed in these relatively young dwarf galaxies.

"Slowly, evidence for this argument accumulated. In 2002, astronomers studying the globular cluster NGC 5634 realized that its position was in the tidal stream of the Sagittarius Dwarf Galaxy. Its motion and metal-poor composition also matched the rest of the dwarf galaxy.

"Since then, astronomers have found compelling evidence that several additional globular clusters are also associated with this tidally tortured galaxy. This includes AM 4, Arp 2, Pal 12, NGC 2419, NGC 4147, Terzan 7, Terzan 8, Whiting 1.

"In the meantime, other streams of torn apart dwarf galaxies were discovered, including the Helmi stream, the Gaia-Enceladus Sausage, the Sequoia galaxy, among others. Associations with additional globular clusters soon followed.

"In addition to galaxies currently undergoing cannibalization, astronomers have also proposed that some of the more intact dwarf galaxies orbiting the Milky Way may have contributed globular clusters (as well as potentially poaching some of their own).

***

"In their first paper, they modeled hypothetical dwarf galaxies (populated with globular clusters) in various orbits around the Milky Way to explore how easily their clusters could be separated from their host galaxy.

"They found that the percentage of clusters pulled off varied anywhere from 12% to 93%. The clusters were more likely to be extracted if they had elliptical orbits that took them into the outskirts of their host galaxies. However, if the galaxy was more massive, it would be able to hold on to its clusters better.

"Based on this range of simulations, the paper suggested that at least two globular clusters would have been the Fornax Galaxy, four from the Large Magellanic Cloud, two from the Small Magellanic Cloud, and 14 from the Sagittarius Dwarf Galaxy.

***

"Ultimately, their review finds that 29 (19%) of the known globular clusters had properties sufficiently similar to the dwarf galaxies reviewed to be considered associated.

"The authors do admit that their models are somewhat simplistic, as they do not fully model the complex 3-dimensional structure of the dwarf galaxies. While such computations are possible with modern computers, because the authors ran the simulations numerous times with varying parameters, doing so would still have been challenging."

Comment: as a very large galaxy we simply pull in the others. Be sure to see the illustration.

631 views

So cold it won't melt in Neptune and Uranus:

https://www.sciencealert.com/strange-form-of-ice-found-that-only-melts-at-extremely-hot...

"...hot, black, heavy ice – that's both solid and liquid at the same time – likely forms within the water-rich gas giants, Uranus and Neptune.

"Five years ago, scientists recreated this exotic ice, called superionic ice, for the first time in lab experiments; and four years ago they confirmed its existence and crystalline structure.

"Then just last year, researchers at several universities in the United States and the Stanford Linear Accelerator Center laboratory in California (SLAC) discovered a new phase of superionic ice.

"Their discovery deepens our understanding as to why Uranus and Neptune have such off-kilter magnetic fields with multiple poles.

"From our earthly surrounds, you'd be forgiven for thinking water is a simple, elbow-shaped molecule made up of one oxygen atom linked to two hydrogens that settle into a fixed position when water freezes.

"Superionic ice is strangely different, and yet it may be among the most abundant forms of water in the Universe – presumed to fill not only the interiors of Uranus, Neptune, but also similar exoplanets.

"These planets have extreme pressures of 2 million times the Earth's atmosphere, and interiors as hot as the surface of the Sun – which is where water gets weird.

"Scientists confirmed in 2019 what physicists had predicted back in 1988: a structure where the oxygen atoms in superionic ice are locked in a solid cubic lattice, while the ionized hydrogen atoms are let loose, flowing through that lattice like electrons through metals.

"This gives superionic ice its conductive properties. It also raises its melting point such that the frozen water remains solid at blistering temperatures.

***

"X-ray diffraction then revealed the hot, dense ice's crystal structure, despite the pressure and temperature conditions only being maintained for a fraction of a second.

"The resulting diffraction patterns confirmed the ice crystals were in fact a new phase distinct from superionic ice observed in 2019. The newly discovered superionic ice, Ice XIX, has a body-centered cubic structure and increased conductivity compared to its predecessor from 2019, Ice XVIII.

"Conductivity is important here because moving charged particles generate magnetic fields. This is the basis of dynamo theory, which describes how churning conductive fluids, such as Earth's mantle or inside another celestial body, give rise to magnetic fields.

***

"Gleason and colleagues conclude the enhanced conductivity of a layer of superionic ice akin to Ice XIX would promote the generation of wonky, multipolar magnetic fields like those emanating from Uranus and Neptune.

"If so, it would be a satisfying result more than 30 years after NASA's Voyager II space probe, launched in 1977, flew by our Solar System's two ice giants and measured their highly unusual magnetic fields."

Comment: this adds to the many properties water can have besides being vital for life to exist.

641 views

Just discovered:

https://mail.google.com/mail/u/0/#inbox/FMfcgzGwHLfLNTfSMvhDkRvdKVlwKCxD

"Scientists from the United States and Australia have for the first time seen intergalactic gas filaments. These gas filaments are mostly made of hydrogen. Because hydrogen is the simplest element, a lot of it was created in the early universe. If it clumps enough, it forms stars and solar systems and galaxies. But where it doesn’t clump it just lingers around and it’s hard to see. And yet, seeing this stuff is important to confirm that our model of the universe is correct. ( my bold)

"Measuring this hydrogen is really difficult. They did it by looking for a particular emission line of hydrogen, known as the Lyman alpha line. If hydrogen atoms wiggle, this is one of the wavelengths they emit. The Lyman alpha line is in the ultraviolet when emitted, so we can’t see it. But the universe expands while the light travels towards us, so the wavelength stretches, and it’s shifted into the visible range. These emission lines are faint and difficult to tease out of the data from the rest of the universe’s light.

"They did it with instrument called the Cosmic Web Imager at the Keck Observatory in Hawaii using a sophisticated background removal technique called nod-and-shuffle. This entails shifting the focus of the instrument from the source you want to image to its background and tracking how the combination of both changes. Then you can identify and subtract much of the background.

"The sources they looked at were at redshift around 2 point 5, so about 10 billion light-years away. The volume that their observations covered is a slice of roughly 3 million light-years wide and 600 million light-years long. So it ain’t small.

"If dark matter exists, which it may not, then it should fit with the structure of these filaments, so measuring them is another way to probe dark matter. It’s an important test because most of the *normal matter in our universe is actually not in stars, but floats around as such barely visible gas, either inside of galaxies or between them.

"Space is really a bit like society, the stars attract all the attention, but the real power is in the dark web."

Comment: Thanks to Sabine Hossenfelder for this coverage and her analysis.

642 views

Shown by mathematics:

https://www.math.columbia.edu/~woit/righthanded.pdf

"Abstract
The relation between vectors and spinors in complex spacetime is conventionally defined so
that Minkowski spacetime is related by Wick rotation to the standard Euclidean four-dimensional geometry. There is a different chirally asymmetric possibility, using purely right-handed spinors, in which Minkowski spacetime gets Wick rotated to a four-dimensional geometry with a distinguished direction. This right-handed spinor geometry also gives self-dual two-forms that can be used to get chiral formulations of the Yang-Mills and general relativity actions.

***

The Standard Model quantum field theory is not well-defined in Minkowski spacetime
without some further information, with analytic continuation from Euclidean spacetime one
way to accomplish this. Defining the theory this way allows one to exploit the symmetries of
the Euclidean spacetime, and in [10] we described a speculative proposal for understanding
the symmetries of the Standard Model in terms of the geometry of the Euclidean version of
twistor space. Such a twistor space description is inherently completely chirally asymmetric, with points in spacetime corresponding to spinors of one chirality. The most unconventional part of the proposal is that the part of the Euclidean rotation group that acts on the other chirality could physically correspond not to a spacetime symmetry but to an internal symmetry. The main goal of this paper has been to understand the possible origin of such a counter-intuitive phenomenon. Note however that mixing between Euclidean rotational symmetry and an internal symmetry has been seen in other contexts, in particular in the twisting used to define topological quantum field theories.

The conventional way of relating Euclidean and Minkowski spacetime spinors is by a
chirally symmetric analytic continuation which takes Euclidean spacetime symmetries to
Minkowski spacetime symmetries for both chiralities. In this paper we have proposed a
different relation, which uses just one chirality. Spacetime (both Minkowski and Euclidean)
can be said to be “right-handed”, and we see that this goes beyond the spin 1/ 2 matter degrees of freedom, with Yang-Mills and gravitational dynamics also described using right-handed spinors...This proposal is set in Minkowski spacetime.

Comment: All of the complex calculus equations are omitted. Chirality of spacetime is an interesting concept. Does it mean there is another left-handed universe for symmetry or is it like biochemistry where mechanisms are always one way or the other without balance.

598 views

James Webb telescope latest findings:

https://phys.org/news/2023-11-astronomers-webb-rapid-oxygen-early.html

"Using new data from the James Webb Space Telescope, astronomers have measured the abundance of oxygen in the early universe. The findings, accepted for publication in The Astrophysical Journal Supplement Series and posted to the arXiv preprint server, show that the amount of oxygen in galaxies increased rapidly within 500–700 million years after the birth of the universe, and has remained as abundant as observed in modern galaxies since then. This early appearance of oxygen indicates that the elements necessary for life were present earlier than expected.

"In the early universe, shortly after the Big Bang, only light elements such as hydrogen, helium, and lithium existed. Heavier elements like oxygen were subsequently formed through nuclear fusion reactions within stars and dispersed into galaxies, primarily through events like supernova explosions. This ongoing process of element synthesis, unfolding over the vast expanse of cosmic history, created the diverse elements that constitute the world and living organisms around us.

"A research team led by Kimihiko Nakajima at the National Astronomical Observatory of Japan used data from the James Webb Space Telescope (JWST) to measure the oxygen in 138 galaxies that existed in the first 2 billion years of the universe. The team found that most of the galaxies had oxygen abundances similar to modern galaxies. But out of the seven earliest galaxies in the sample, those that existed when the universe was only 500–700 million years old, six of them had roughly half the predicted oxygen content.

"This rapid increase in oxygen content occurred earlier than astronomers were expecting. This opens the possibility that with the necessary ingredients, like oxygen, already readily available in the early universe that life may have appeared sooner than previously thought."

Comment: From a purpose standpoint, knowing in advance how vital oxygen would be for most life, providing for large amounts early makes perfect design sense.

569 views

The icy pebble drift theory confirmed:

https://www.sciencealert.com/jwst-may-have-finally-confirmed-how-planets-take-shape

"JWST data processed by an international team of researchers backs up the theory of 'icy pebble drift', which is thought to be vital in bringing together the dust and rocks that eventually turn into planets like our own.

"Simply put, icy pebble drift works like this: as tiny, ice-covered bits of material bump together in the outer reaches of a young protoplanetary disk they lose momentum, allowing them to fall towards the star into a warmer zone where their frozen coating sublimates.

"It's from this ring of fine debris and water vapor that rocky planets form, effectively serving as a delivery service of building materials right across a newborn solar system.

'As neat as the idea was, studies of distant starlight that could indicate the position of that water vapor have so far been too blurry to conclusively say for certain whether this drift of icy pebbles takes place at all.

***

"What the new research shows is that icy materials can indeed move across protoplanetary disks, though it happens more easily on compact disks.

"'In the past, we had this very static picture of planet formation, almost like there were these isolated zones that planets formed out of," says planetary scientist Colette Salyk from Vassar College.

"'Now we actually have evidence that these zones can interact with each other. It's also something that is proposed to have happened in our Solar System."

"By comparing the data from both compact and extended disks, the team was able to see more water vapor collected at the 'snowline' of the compact disk, where icy pebbles should lose a lot more vapor.

"That backs up the idea that building materials can move inward across the disk, a phenomenon that is more efficient in compact disks where large gaps don't need to be traversed. As the sublimating stream of pebbles continue to snow down from the beyond, they provide both solids and water to create the seeds of a new planet, so the theory goes."

Comment: Another use for water as ice, just adding to the evidence as to how important water is not just for life but for making the universe's parts. Hydrogen and oxygen were among the earliest elements to appear. Then magical water. Pure evidence for purpose in design.

558 views

Not in solar systems:

https://www.quantamagazine.org/rogue-worlds-throw-planetary-ideas-out-of-orbit-20231113/

“'When we look at the solar system it’s all nice and neat. You get the sun, and you get planets,” said Samuel Pearson, an astronomer with the European Space Agency (ESA). There’s nothing in the middle. But “when you actually go and have a look,” Pearson said, “you realize there’s a full spectrum of [objects with] basically every mass in between.”

"The JWST observation bolsters a growing catalog of isolated objects occupying this gray zone between giant planets and tiny stars. Sometimes called “free-floating” or “rogue” planets, these solitary worlds drift freely through space. While astronomers can estimate the mass of these dark, Jupiter-mass balls of gas, their origins remain mysterious. Are they actually planets — “Jupiters” that once orbited stars but were somehow spit out? Or are they more like micro-stars that failed to ignite?

"Rather than answering this question, the JWST observation adds to the mystery: The telescope’s infrared eye found that dozens of the worlds appear to be in pairs orbiting each other — a puzzling arrangement that, if confirmed, would defy expectations.

***

"improbable duos cannot be easily explained by any known formation theories of either stars or free-floating planets. But within a week of the JWST announcement, researchers published a daring new idea describing how giant planets might be ejected from their home system in pairs — an event most researchers had thought all but impossible. Whether or not the proposal can fully account for the entire zoo of dim, starless worlds remains to be seen. But researchers expect that a refined understanding of free-floating worlds, and the star systems that create them, is at hand.

“'If indeed [this discovery] is confirmed,” said Peter Plavchan, an astrophysicist at George Mason University who was not involved in detecting the pairs of Jupiters, “it will truly be groundbreaking.”

***

"From a theoretical perspective, these duos seemed nearly impossible. They were unlikely to be punted planets; when one planet kicks another out of a stellar system, the ejected planet almost always flies off alone. But they couldn’t be stars either, since many of them weighed as little as a single Jupiter — a mass too light for the object to have formed directly from a collapsing gas cloud. The team dubbed their mystery duos Jupiter Mass Binary Objects, or JUMBOs for short, and described them in a preprint posted on October 2.

"The JUMBOs caught experts in both star and planet formation flat-footed. “This has not been predicted at all. There are no existing theories where we would have expected these wide, free-floating planetary objects in these numbers,” said Matthew Bate, an astrophysicist at the University of Exeter specializing in star formation.

***

"In the spring, Pearson and McCaughrean will use JWST to again observe their batch of free-floating worlds, this time in a richer spectrum of colors. These follow-up observations will help confirm which JUMBOs are real by looking for traces of methane or water in their atmospheres, a telltale signature of Jupiter-mass worlds.

“'Once you’ve got spectra,” Pearson said, “there’s basically no place to hide.'”

Comment: the universe gets more mysterious and complex the deeper we can look. This will delight dhw who always questions God's works. Why create this mass of independent objects if all God wanted was us on Earth? dhw's puny brain against God's. God works in mysterious ways, doesn't HE?

586 views

One for what we see and one for dark matter:

https://bigthink.com/hard-science/two-big-bangs/?utm_campaign=weeklynewsletter&utm_...

"The moment that the Universe transitioned from being governed by inflation to being filled with a hot and dense plasma is the beginning of what scientists call the Big Bang.

"The other interesting phenomenon is dark matter, a proposed substance that, if it exists, explains some observed astronomical anomalies. Galaxies, like people, are made of ordinary matter, and we can use the laws of physics to predict how they should move. However, when astronomers study the heavens, they see some surprises. One example is that galaxies rotate faster than expected. A second example is that certain galaxy clusters shouldn’t exist, as individual galaxies are moving so fast that they should escape the gravitational attraction of their neighbors.

***

"In the prevailing theory of the origins of the Universe, both familiar matter and dark matter were created at the same time, less than a second after the Universe began. Effectively, it is thought that a series of steps converted the energy that governed inflation into matter and dark matter.

", the new paper raises a different possibility. Given that ordinary matter and dark matter only interact via gravity, perhaps they didn’t appear at the same time in the early Universe. This paper suggests that while the energy of inflation eventually transitioned into ordinary matter, dark matter might have had a different origin. In the new theory, there was a second form of energy, similar to the vacuum energy that caused inflation, but this new energy was dark vacuum energy, which became the origin of dark matter.

***

"Can this new idea be tested? If dark matter and ordinary matter interact only via gravity, the dozens of dark matter experiments currently underway will fail. All of them depend on dark matter and ordinary matter experiencing some sort of interaction beyond gravity. Thus, if this new theory is right, that would be disappointing.

"However, when the dark vacuum energy transitioned into dark matter particles, that change of energy would have shaken the structure of space and time, creating gravitational waves that would fill the Universe. Metaphorically at least, this would appear to be a “hum” in the structure of space.

"Very precise experiments have already reported detecting a cosmic hum, but a bit of caution is warranted. There are several astronomical phenomena that can generate a similar hum. Thus, the recent detection is not a confirmation this new theory. That will take more data and far more sophisticated analysis. However, the fact that facilities exist that can detect the right kind of gravitational waves gives us hope that researchers will be able to confirm or disprove this idea within a few years."

Comment: at least this far out theory can be tested.

594 views

The issue is dark matter gravity effects or modified gravity theory (MOND):

https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stad3393/7342478

" Abstract
We test Milgromian dynamics (MOND) using wide binary stars (WBs) with separations of 2 − 30 kAU. Locally, the WB orbital velocity in MOND should exceed the Newtonian prediction by
at asymptotically large separations given the Galactic external field effect (EFE). We investigate this with a detailed statistical analysis of Gaia DR3 data on 8611 WBs within 250 pc of the Sun. Orbits are integrated in a rigorously calculated gravitational field that directly includes the EFE. We also allow line of sight contamination and undetected close binary companions to the stars in each WB. We interpolate between the Newtonian and Milgromian predictions using the parameter αgrav, with 0 indicating Newtonian gravity and 1 indicating MOND. Directly comparing the best Newtonian and Milgromian models reveals that Newtonian dynamics is preferred at 19σ confidence. Using a complementary Markov Chain Monte Carlo analysis, we find that ⁠, which is fully consistent with Newtonian gravity but excludes MOND at 16σ confidence. This is in line with the similar result of Pittordis and Sutherland using a somewhat different sample selection and less thoroughly explored population model. We show that although our best-fitting model does not fully reproduce the observations, an overwhelmingly strong preference for Newtonian gravity remains in a considerable range of variations to our analysis. Adapting the MOND interpolating function to explain this result would cause tension with rotation curve constraints. We discuss the broader implications of our results in light of other works, concluding that MOND must be substantially modified on small scales to account for local WBs. "

Comment: a strong blow against MOND. Dark matter wins.

553 views

In our region of the universe:

https://www.universetoday.com/164414/there-arent-many-galaxies-like-the-milky-way-nearb...

"The Milky Way is a barred spiral galaxy, maybe even a grand design spiral galaxy. We can’t be sure from our vantage point. But one thing is certain: there aren’t many disk galaxies like it in our part of the Universe called the supergalactic plane.

"We can locate things on Earth using compass points and latitudes and longitudes. But in space, that doesn’t work. Astronomers use the supergalactic coordinate system to describe where galaxies are.

"Part of that coordinate system is the Supergalactic Plane (SGP), which contains the Local Group of galaxies that the Milky Way is in. The SGP is nearly perpendicular to the Milky Way’s plane.

"The supergalactic plane is part of a reference system for the Local Universe. It’s a flat, enormous circle one billion light-years across, though this image only shows part of it. It’s centred on the Local Group, which is where the Milky Way resides.

***

"But scientists do know that the SGP is filled with galaxies. Bright elliptical galaxies dominate the SGP, while spirals like the Milky Way are rare. The paucity of spiral galaxies caught the attention of a group of researchers from Europe. They used supercomputer simulations to try to gauge the population and distribution of galaxies in the SGP.

***

“'Galaxies of different types are not equally distributed in the Local Universe,” the researchers write in their paper. “The supergalactic plane is prominent among the brightest ellipticals but inconspicuous among the brightest disk galaxies.”

***

"Sawala and his colleagues found that the distribution of ellipticals and spirals is because of the different conditions inside and outside of the SGP. Inside, galaxies are more tightly packed together, and outside of the SGP, the galactic density is lower.

"Inside the SGP, galaxies interact and merge with each other more frequently. These interactions change beautiful spirals like the Milky Way into ellipticals, which are basically ellipses or spheres with no discernible arms.

"But outside of the SGP, galaxies interact less frequently. So the Milky Way and others like it are able to retain their form. (my bold)

“'We find that SIBELIUS DARK reproduces the spatial distributions of disks and ellipticals and, in particular, the observed excess of massive ellipticals near the supergalactic equator,” the researchers write.

"The SIBELIUS results are in line with observations, which helps confirm its usefulness. “This mass difference agrees with observational studies of galaxies in the Local Universe, which also find that the most massive galaxies are overwhelmingly elliptical,” Sawala and his colleagues write in their paper.

"To grow large, disk galaxies like the Milky Way need a supply of gas and minimal interactions with other galaxies. That environment is found outside of the SGP. “We conclude that the environment prevailing in the supergalactic plane inhibits the conditions necessary for massive disk formation: a quiet merger history and the continuous supply of cold gas,” the authors explain.

***

“'The strikingly different distributions of bright ellipticals and disks in relation to the supergalactic plane do not require physics beyond the standard model,” they write. Instead, the distributions relative to the SGP “arise naturally in the Lambda CDM framework.” The distribution is a part of the standard model of how galaxies form and evolve.

"For us, it doesn’t make much difference whether we live in a spiral/disk galaxy or in an elliptical. But examining how our type of galaxy fits into nature is worth exploring. These results strengthen the already powerful arguments in favour of the Lambda CDM model.

"Now, if we could only figure out what the heck dark matter actually is."

Comment: The SGP is a slice across the plane of the galaxy, a cross-sectional view which is a very informative result. It tells us big spirals are not as common as ellipticals. What does that mean to my theory God is/was designing a universe for us. Is our privileged planet in a privileged galaxy? Note my bold. Merging galaxies create a very chaotic situation as gravity from two directions pulls things apart. For life to continue, the last thing we need is a merger, and in two million years we merge with Andromeda. If God is in charge, does that mean the length of our time of life has limits?

508 views

It shouldn't be there:

https://www.sciencealert.com/key-ingredient-for-life-discovered-in-the-last-place-astro...

"Generating life out of an organic soup is a complicated business. You need a whole bunch of ingredients, all together in the same place, in the right conditions.

"While the precise conditions might be is still a matter of debate, we have a decent idea of which items on the periodic table are required.

"One critical ingredient – phosphorus – has just been found on the outskirts of the Milky Way galaxy; one of the last places scientists expected to see it. That's because the kinds of huge stars responsible for the creation of phosphorus aren't generally found out there.

"'To make phosphorus, you need some kind of violent event," says astronomer and chemist Lucy Ziurys of Arizona State University and Steward Observatory. "It is thought that phosphorus is created in supernova explosions, and for that, you need a star that has at least 20 times the mass of the Sun."

"So goes the conventional wisdom, anyway. The discovery of phosphorus far from any massive stars or supernova remnants suggests that there may be some other means of forging the life-crucial element.

***

"But the elements a star produces depends on its mass. Stars the size of our Sun and smaller can facilitate fusion reactions that build lightweight elements like lithium and berylium as they fuse hydrogen and helium. Another form of fusion can take place in much larger stars which can result in elements like oxygen and nitrogen.

"Phosphorus isn't on either stellar fusion chain; but one way it is known to form is during supernova explosions.

"There's another benefit to supernova explosions, which only happen to stars of high mass: they blast elements into space, seeding the interstellar medium with heavy ingredients that are taken up by new generations of stars, and other objects such as comets and planets.

"But massive stars can only form in regions where there is enough material to feed them. Matter gets sparser the farther you go from the center of the galaxy, so massive stars aren't expected to be able to form on the outskirts. This makes the discovery of phosphorus in a cloud known as WB89-621 some 74,000 light-years from the heart of the Milky Way a big dang puzzle.

***

"A few years ago, astronomers found that less massive stars could produce phosphorus, too. Not in an explosion, but in the region just around their core through a process known as neutron capture. There, isotopes of silicon could snare extra neutrons to form phosphorus.

"The discovery of phosphorus far from the source of any supernova suggests that this model may be onto something.

"And this is really exciting news, because phosphorus is the last of the so-called NCHOPS elements – nitrogen, carbon, hydrogen, oxygen, phosphorus and sulfur – to be identified in the galactic outskirts. (my bold)

"'For a planet to be habitable to life as we know it, you have to have all the NCHOPS elements, and their presence defines the galactic habitable zone," Ziurys says. "With our discovery of phosphorus, all of them have now been found at the edge of the galaxy, which extends the habitable zone all the way out to the galactic outskirts.'"

Comment: my view is God prefers to evolve His creations, as the element making in stars shows. Making sure phosphorous was everywhere in the Milky Way means God planned for life in our galaxy.

469 views

And it may be experimentally verified:

https://phys.org/news/2023-12-theory-einstein-gravity-quantum-mechanics.html

"The prevailing assumption has been that Einstein's theory of gravity must be modified, or "quantized," in order to fit within quantum theory. This is the approach of two leading candidates for a quantum theory of gravity, string theory and loop quantum gravity.

"But a new theory, developed by Professor Jonathan Oppenheim (UCL Physics & Astronomy) and laid out in a paper in Physical Review X, challenges that consensus and takes an alternative approach by suggesting that spacetime may be classical—that is, not governed by quantum theory at all.

"Instead of modifying spacetime, the theory—dubbed a "postquantum theory of classical gravity"—modifies quantum theory and predicts an intrinsic breakdown in predictability that is mediated by spacetime itself. This results in random and violent fluctuations in spacetime that are larger than envisaged under quantum theory, rendering the apparent weight of objects unpredictable if measured precisely enough.

"A second paper, published simultaneously in Nature Communications and led by Professor Oppenheim's former Ph.D. students, looks at some of the consequences of the theory, and proposes an experiment to test it: to measure a mass very precisely to see if its weight appears to fluctuate over time.

"For example, the International Bureau of Weights and Measures in France routinely weigh a 1kg mass which used to be the 1kg standard. If the fluctuations in measurements of this 1kg mass are smaller than required for mathematical consistency, the theory can be ruled out.

"The outcome of the experiment, or other evidence emerging that would confirm the quantum vs. classical nature of spacetime, is the subject of a 5000:1 odds bet between Professor Oppenheim and Professor Carlo Rovelli and Dr. Geoff Penington—leading proponents of quantum loop gravity and string theory respectively.

***

"Professor Oppenheim said, "Quantum theory and Einstein's theory of general relativity are mathematically incompatible with each other, so it's important to understand how this contradiction is resolved. Should spacetime be quantized, or should we modify quantum theory, or is it something else entirely? Now that we have a consistent fundamental theory in which spacetime does not get quantized, it's anybody's guess."

"Co-author Zach Weller-Davies, who as a Ph.D. student at UCL helped develop the experimental proposal and made key contributions to the theory itself, said, "This discovery challenges our understanding of the fundamental nature of gravity but also offers avenues to probe its potential quantum nature.

"'We have shown that if spacetime doesn't have a quantum nature, then there must be random fluctuations in the curvature of spacetime which have a particular signature that can be verified experimentally.

"'In both quantum gravity and classical gravity, spacetime must be undergoing violent and random fluctuations all around us, but on a scale which we haven't yet been able to detect. But if spacetime is classical, the fluctuations have to be larger than a certain scale, and this scale can be determined by another experiment where we test how long we can put a heavy atom in superposition of being in two different locations."

"Co-authors Dr. Carlo Sparaciari and Dr. Barbara Šoda, whose analytical and numerical calculations helped guide the project, expressed hope that these experiments could determine whether the pursuit of a quantum theory of gravity is the right approach.

***

"'But what I find exciting is that starting from very general assumptions, we can prove a clear relationship between two measurable quantities—the scale of the spacetime fluctuations, and how long objects like atoms or apples can be put in quantum superposition of two different locations. We can then determine these two quantities experimentally."

"Weller-Davies added, "A delicate interplay must exist if quantum particles such as atoms are able to bend classical spacetime. There must be a fundamental trade-off between the wave nature of atoms, and how large the random fluctuations in spacetime need to be."

"The proposal to test whether spacetime is classical by looking for random fluctuations in mass is complementary to another experimental proposal that aims to verify the quantum nature of spacetime by looking for something called "gravitationally mediated entanglement."

"Professor Sougato Bose (UCL Physics & Astronomy), who was not involved with the announcement today, but was among those to first propose the entanglement experiment, said, "Experiments to test the nature of spacetime will take a large-scale effort, but they're of huge importance from the perspective of understanding the fundamental laws of nature. I believe these experiments are within reach—these things are difficult to predict, but perhaps we'll know the answer within the next 20 years.'"

Comment: like MOND an interesting approach, but if solved 20 years from now, only some of us will learn the answers. I'm doubtful about this approach. The universe is obviously based on an underlying quantum background. I can't imagine it being somehow different in spacetime.

449 views

A study finds a limit of 260 atomic weight:

https://phys.org/news/2023-12-ancient-stars-extraordinarily-heavy-elements.html

"How heavy can an element be? An international team of researchers has found that ancient stars were capable of producing elements with atomic masses greater than 260, heavier than any element on the periodic table found naturally on Earth. The finding deepens our understanding of element formation in stars.

"We are, literally, made of star stuff. Stars are element factories, where elements constantly fuse or break apart to create other lighter or heavier elements. When we refer to light or heavy elements, we're talking about their atomic mass. Broadly speaking, atomic mass is based on the number of protons and neutrons in the nucleus of one atom of that element. (my bold)

"The heaviest elements are only known to be created in neutron stars via the rapid neutron capture process, or r-process. Picture a single atomic nucleus floating in a soup of neutrons. Suddenly, a bunch of those neutrons get stuck to the nucleus in a very short time period—usually in less than one second—then undergo some internal neutron-to-proton changes, and voila! A heavy element, such as gold, platinum or uranium, forms.

***

"'We have a general idea of how the r-process works, but the conditions of the process are quite extreme," Roederer says. "We don't have a good sense of how many different kinds of sites in the universe can generate the r-process, we don't know how the r-process ends, and we can't answer questions like, how many neutrons can you add? Or, how heavy can an element be? So we decided to look at elements that could be made by fission in some well-studied old stars to see if we could start to answer some of these questions."

"The team took a fresh look at the amounts of heavy elements in 42 well-studied stars in the Milky Way. The stars were known to have heavy elements formed by the r-process in earlier generations of stars. By taking a broader view of the amounts of each heavy element found in these stars collectively, rather than individually as is more common, they identified previously unrecognized patterns.

"Those patterns signaled that some elements listed near the middle of the periodic table—such as silver and rhodium—were likely the remnants of heavy element fission. The team was able to determine that the r-process can produce atoms with an atomic mass of at least 260 before they fission.

"'That 260 is interesting because we haven't previously detected anything that heavy in space or naturally on Earth, even in nuclear weapon tests," Roederer says. "But seeing them in space gives us guidance for how to think about models and fission—and could give us insight into how the rich diversity of elements came to be.'"

Comment: we are the results of exploding stars. dhw thinks the universe is too big as designed by God. We need all those exploding stars to be created here.

445 views

Quite unusual:

https://www.sciencenews.org/article/milky-way-bar-young-metal-stars

"The biography of our home galaxy may be due for some revisions. That’s because a bar-shaped collection of stars at the center of the Milky Way appears to be much younger than expected.

"The bar is a prominent feature of our galaxy. It spans thousands of light-years and links the galaxy’s spiraling arms of stars, making them resemble streams of water coming from a spinning lawn sprinkler. In computer simulations of the Milky Way’s evolution, the bar tends to form early in the galaxy’s roughly 13-billion-year lifetime. But the ages and locations of metal-rich stars suggest the bar finished forming just a few billion years ago, researchers report.

***

“'These metal-rich stars are basically like fossil records of ancient stars that are telling the story of our home galaxy,” says Samir Nepal, an astrophysicist at the Leibniz Institute for Astrophysics Potsdam in Germany.

"Stars with large proportions of metal elements are built from the remnants of stars that have since exploded, ejecting the metals they forged from lighter elements. Those spewed metals enrich the materials in the core of galaxies like the Milky Way, which is why a new generation of metal-rich stars can form only deep inside galaxies. The spinning bar at the center of the Milky Way then scattered some of those stars throughout our galaxy.

***

"Using data from the European Space Agency’s Gaia space telescope, Nepal and colleagues reconstructed the development of the Milky Way bar through its influence on the distribution of metal-rich stars. They inferred the bar’s history, just as you might deduce where the batters stand in a baseball game by looking at the flight of the balls they hit, even if you can’t see home plate.

"In tracking the ages of the metal-rich stars, the researchers identified a burst of star formation in the central part of the galaxy that petered out about 3 billion years ago. The downturn seems to mark the end of the Milky Way bar’s developmental phase, the researchers report. After that burst, they say, the inflow of new material into the bar probably dropped off substantially. That suggests the bar we see today is a stable feature that’s about 10 billion years younger than the galaxy as a whole.

"The new insights about the metal-rich stars “are like the tip of the iceberg” of data coming from the Gaia telescope, says astrophysicist Cristina Chiappini, also with the Leibniz Institute for Astrophysics Potsdam. Assuming the revised age estimate of the bar is confirmed, future models of the galaxy’s evolution will have to account for why the bar developed so late.

"The study has broader implications than correcting the history of our galaxy, says Ortwin Gerhard, an astrophysicist at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, who was not involved in the research. “The possibility of detailed observations of the motions and chemical abundances of stars in the Milky Way, particularly based on [data] from the Gaia satellite,” he says, means we can “expect to learn about the evolution of bars [in other galaxies] generally by studying the bar in the Milky Way.'”

Comment: this adds to our understanding of our home galaxy. Whether other barred galaxies have the same history or not, awaits future research. Note how the heavy metal elements were made. Only we can use them. God had them appear just for our use. More obvious proof God prepared for our designed arrival. God is obvious if teleology is used.

426 views

Not understood:

https://www.patreon.com/posts/theres-dark-in-94817488?utm_medium=post_notification_emai...

"The Brick is a boxy cloud of opaque dust at the centre of the Milky Way, which has confused scientists ever since its discovery 30 years ago. It just got even weirder.

"Astrophysicists originally thought that the Brick was just full of dense gases, which would absorb light. But then it should also have been full of young stars born from this dense gas. Yet those are nowhere to be seen. In reality, the Brick is closer to a nunnery than a maternity ward.

"According to the new paper by an international team of astronomers now, the Brick is full of ice crystals, made of carbon monoxide. Carbon monoxide is one of the gasses coming out of car exhaust pipes. You normally don’t see it as ice though, or if you do, maybe you accidentally drove to Saturn, because the freezing point of carbon monoxide is minus 205 degrees Celsius.

"And that’s the stuff the researchers say is in the Brick. They figured this out with Webb’s infrared telescope. They used this to measure how much of the light that came from the other side of the brick was filtered out by it. From this they learned it contained significant amounts of this carbon monoxide ice.

"This is extremely weird because according to our current models of galaxy formations such a cloud just shouldn’t be there. No one has any idea at the moment how it got there or what it’s doing there, it’s very confusing. It’s also very interesting because astrophysicists are still trying to understand the distribution and structure of matter in galactic centers which is super important for the debate whether dark matter of modified gravity is correct."

Comment: we keep finding things in the Milky Way that require further explanation. I follow the principle that everything is there for about reason. Our human curiosity will take us to an answer.

424 views

What is the Earth's fate?:

https://www.quantamagazine.org/new-clues-for-what-will-happen-when-the-sun-eats-the-ear...

"When a main-sequence star like our sun — also called a G-type star or yellow dwarf — reaches the end of its life, it runs out of the hydrogen needed to power nuclear fusion in its core. As the star turns to other fuel sources and loses mass, its core gets hotter, and its atmosphere puffs up over millions of years. Eventually, our sun will grow more than 200 times as wide as its present size.

"That swelling sun will consume Mercury and probably Venus, before growing so large it approaches Earth’s orbit — a distance known as one astronomical unit, or AU. But it could expand even further. “In some models,” said Antonino Lanza, an astronomer at the Astrophysical Observatory of Catania in Italy, “it can engulf Mars.” The main uncertainty, he said, lies in how much mass the sun will lose as it ages; the more it sheds, the smaller its final radius will be. “That is poorly known,” he said.

"For now, our best estimates suggest that the sun will grow to somewhere between 0.85 and 1.5 AU. But as the star loses mass, the weaker pull of gravity will increase Earth’s orbit, meaning our planet could escape engulfment.

'To see Earth’s future, astronomers turn to a crystal ball filled with alien planetary systems. Their goal is to find sunlike stars that will soon balloon (or have just ballooned) into red giants.

"That’s why Rho Coronae Borealis, a nearby yellow dwarf star that’s thought to be reaching the end of its sunny life, caught Kane’s attention. Three of its four known planets orbit close to the star, well within Venus’ path around our sun. The outermost planet, with a year lasting 282 days, is similar in orbit to Venus.

"Kane’s analysis, published last month, shows that the growing star will engulf the three inner planets. The innermost of those worlds, thought to be rocky and nearly four times the mass of Earth, will evaporate within a few hundred years. “The plasma superheats the planet and causes it to essentially break down,” Kane said. “Even the rocks on the surface will melt away.” The next world out, a Jupiter-mass gas giant, is so large that it will spiral inward and be ripped apart by the star’s gravity, rather than evaporating. The third planet, a smaller Neptune-mass world, will likely also be engulfed and evaporated.

***

"In the past two decades, scientists have found a handful of exoplanets orbiting white dwarfs, said Mary Anne Limbach, an exoplanet scientist at the University of Michigan. These planets survived their star’s red giant phase, although it’s not clear exactly how. Some of the worlds — which tend to be larger gas giants — were probably too far from their star to be swallowed, while others may have been pushed outward as the star huffed and puffed. (Astronomers have also seen evidence that some planets were not so lucky in the form of polluted white dwarfs, which are rich in elements associated with planets, such as magnesium and iron.) Ongoing observations by the James Webb Space Telescope (JWST) are expected to turn up dozens more exoplanets orbiting white dwarfs.

"As unusual as they might seem, these planetary systems could still be habitable, said Limbach, who leads some of the JWST white dwarf observations. “There is a place around a white dwarf where you can get liquid water” on a planet’s surface, she said. But “it’s a very challenging environment.”

"More observations of evolved solar systems, and more models like Kane’s, could provide greater insight into the fate of our own. For now, the death of our planet is a roll of the dice away from certainty. Humans may be long gone from Earth’s surface, but anyone glancing in our direction 5 billion years from now might see our planet ride out our sun’s dying breaths — or, perhaps, disappear in a brief flash of light."

Comment: if we are the only life in the universe, our Sun will kill us off, and habitability won't be an issue.

381 views

New research on how to do it:

https://www.universetoday.com/164932/finally-a-productive-use-for-nuclear-weapons-aster...

"Finally. A Productive Use for Nuclear Weapons: Asteroid Defense
While it has been a favorite disaster movie theme, nuking an incoming asteroid in the real world has been touted as a very bad idea. While a nuclear bomb could possibly obliterate a smaller asteroid, nuking a larger asteroid would only break it into pieces. Those pieces would still threaten our planet, and perhaps even makes things worse by producing multiple impacts across the planet.

"But is using nuclear weapons on an incoming asteroid really a bad idea? If the right technique is used, a nuclear blast could possibly be used as an asteroid deflection device.

"Researchers at Lawrence Livermore National Laboratory (LLNL) have now created a modeling tool that can simulate what might happen if a nuclear device is detonated above the surface of an asteroid. The tool is helping to improve the understanding of how the radiation from a nuclear blast interacts with an asteroid’s surface, and also looks at the shockwave dynamics that might affect the inner asteroid.

"The explosive technique called nuclear ablation, where the blast’s radiation would vaporize part of the asteroid’s surface, generating an explosive thrust and a change in velocity in response.

"The model can incorporate a wide range of initial conditions which simulate the kinds of asteroids we’ve recently been able to study up close, from solid rocks to rubble piles. These simulations are giving planetary scientists more insights –and more options – for when a space rock might one day be bearing down on Earth.

“'If we have enough warning time, we could potentially launch a nuclear device, sending it millions of miles away to an asteroid that is headed toward Earth,” said researcher Mary Burkey from LLNL. “We would then detonate the device and either deflect the asteroid, keeping it intact but providing a controlled push away from Earth, or we could disrupt the asteroid, breaking it up into small, fast-moving fragments that would also miss the planet.”

"Thanks to the Double Asteroid Redirection Test (DART) mission – where a kinetic impactor was deliberately crashed into an asteroid to alter its trajectory — scientists have learned much about what it would take to redirect a dangerous asteroid. This new model, called the X-ray energy deposition model, gives researchers the tools to build upon the insights gained from DART while exploring how nuclear ablation could be a viable alternative to kinetic impact missions.

"Burkey said in a LLNL press release that nuclear devices have the highest ratio of energy density per unit of mass of any human technology, which could make them an invaluable tool in mitigating asteroid threats.

"But, as the team wrote in their paper, published in The Planetary Science Journal, “predicting the effectiveness of a potential nuclear deflection or disruption mission depends on accurate multiphysics simulations of the device’s X-ray energy deposition into the asteroid and the resulting material ablation.”

"The team said the relevant physics in these simulations require a variety of different complex physics packages, they span many orders of magnitude and are computationally very demanding. Burkey and her colleagues set the goal of developing an efficient and accurate way of modeling nuclear deflection for a range of physical properties of an asteroid.

"Burkey said that their high-fidelity simulations can track photons penetrating surfaces of asteroid-like materials such as rock, iron, and ice, while accounting for more complex processes, such as reradiation. The model also considers a wide variety of asteroid bodies. They said this comprehensive approach makes the model applicable to a wide range of potential asteroid scenarios.

"If a real planetary defense emergency should arise, Megan Bruck Syal, LLNL’s planetary defense project lead, said this high-fidelity simulation modeling will be critical in providing decision-makers with actionable, risk-informed information that could prevent asteroid impact, protect essential infrastructure and save lives, explained."

Comment: nuclear war on asteroids is the best use for the world's nuclear arsenals. A two-way protection for the human race.

397 views

That is the general shape seen:

The Early Universe Was Bananashttps://www.spacequarter.com/galaxies-in-the-early-universe-were-shaped-like-ban...

"Rather than eggs or discs, baby galaxies appear to have peculiar shapes, such as bananas, pickles, cigars, or surfboards – take your pick of metaphors. A team of astronomers re-examined images of approximately 4,000 newborn galaxies observed by the Webb telescope during the early stages of the universe, leading them to this surprising conclusion.

***

"If this result holds true, it could have significant implications for our understanding of how galaxies form and evolve. Additionally, it may offer insights into the mysterious nature of dark matter, an invisible form of matter that is believed to make up a substantial portion of the universe, outweighing atomic matter by a ratio of 5 to 1. Dark matter envelops galaxies and provides the gravitational nurseries where new galaxies emerge.

"The discovery builds on earlier observations from the Hubble telescope, which suggested that the earliest galaxies had pickle-like shapes, according to Joel Primack, an astronomer at the University of California, Santa Cruz, and a co-author of the new paper.

"While the result is considered important, some scientists maintain a level of skepticism due to the difficulty of making such measurements, particularly for galaxies that are far away, small, and not very bright.

***

"Galaxies are like the city-states of the cosmos, with an estimated two trillion existing within the visible universe. Each galaxy can contain as many as a trillion stars. However, the visible universe represents only a fraction of what lies beyond. Most of the matter in the cosmos is believed to be dark matter, which constitutes the invisible framework of the universe we observe.

"According to current theories, galaxies were formed from random fluctuations in the density of matter and energy during the Big Bang. As space expanded, denser areas lagged behind, causing dark matter to accumulate and pull normal matter with it. Eventually, this material came together and started emitting light as stars and galaxies or collapsed into black holes. The Webb telescope was designed to investigate this formative and enigmatic era, allowing scientists to observe the most distant and earliest galaxies with its giant mirror and infrared sensors.

***

"However, astronomers have observed a different pattern. Instead of round shapes, they have observed many elongated shapes resembling cigars or bananas. These oblong galaxies are rare in the present universe but make up a significant portion of the galaxies in the CEERS sample, which reaches back approximately 500 million years after the Big Bang. These galaxies have masses similar to those of galaxies like the Milky Way, suggesting that our own galaxy may have undergone a similar cigar/surfboard-shaped phase in its past.

"In the modern universe, galaxies typically fall into two categories: featureless, roundish clouds known as ellipticals, and flat, disc-like structures like our Milky Way. However, it seems that the earliest galaxies did not start out this way. The peculiar shapes observed in these baby galaxies are suspected to be related to the properties of dark matter, although the specifics remain unclear."

Comment: the more we learn about the universe the more we need to learn. I did not include a discussion of dark matter effects theories.

273 views

Latest conclusion from a ten-year study:

https://www.sciencealert.com/most-precise-measure-of-dark-energy-confirms-universe-wont...

"The announcement in New Orleans may take us closer to a better understanding of this form of energy. Among other things, it gives us the opportunity to test our observations against an idea called the cosmological constant that was introduced by Albert Einstein in 1917 as a way of counteracting the effects of gravity in his equations to achieve a Universe that was neither expanding nor contracting. Einstein later removed it from his calculations.

***

"The DES results are the culmination of decades of work by researchers around the globe and provide one of the best measurements yet of an elusive parameter called "w", which stands for the "equation of state" of dark energy. Since the discovery of dark energy in 1998, the value of its equation of state has been a fundamental question.

"This state describes the ratio of pressure over energy density for a substance. Everything in the Universe has an equation of state.

"Its value tells you whether a substance is gas-like, relativistic (described by Einstein's theory of relativity) or not, or if it behaves like a fluid. Working out this figure is the first step to really understanding the true nature of dark energy.

"Our best theory for w predicts that it should be exactly minus one (w=-1). This prediction also assumes that dark energy is the cosmological constant proposed by Einstein.

"An equation of state of minus one tells us that as the energy density of dark energy increases, so the negative pressure also increases. The more energy density in the Universe, the more repulsion there is – in other words, matter pushes against other matter. This leads to an ever-expanding accelerating Universe. It might sound a bit bizarre, as it is counterintuitive to everything we experience on Earth.

***

"..this measurement may signal the end of "Big Rip" models which have equations of state that are more negative than one. In such models the Universe would expand indefinitely at a faster and faster rate – eventually pulling apart galaxies, planetary systems and even space-time itself. That's a relief.

Comment: that's a relief if correct. An ever-expanding universe at an ever-increasing rate certainly suggests it could tear up.

302 views

Hossenfelder adds her opinion:

https://www.patreon.com/posts/our-universe-not-96470792?utm_medium=post_notification_em...

"The Dark Energy Survey has surveyed dark energy and found that our universe is unlikely to rip into pieces. I think that’s good news. Let’s have a look.

"Dark Energy is the name that astrophysicists have given to a hypothetical ingredient of the universe that makes the expansion of the universe faster. So it’s not that dark energy causes the expansion itself, it makes it faster. Dark energy should not be confused with dark matter, which *does contribute to the expansion of the universe but doesn’t make it faster.

***

"In astrophysics the name “dark energy” isn’t used for just one thing. It’s a term that encompasses all kinds of different things which could cause this accelerated expansion. One of these types of dark energy is the cosmological constant, usually denoted with a capital lambda. So the cosmological constant relates to dark energy like a banana relates to fruits. It’s one of many.

"The cosmological constant is, would you have guessed it, constant, and it’s the simplest type of dark energy. But like there are other fruits besides bananas there are other types of dark energy besides the cosmological constant.

***

"And this brings me to the new data from the dark energy survey. They measured this w by looking at light from distant supernovae. The survey was conducted with a camera mounted on the Victor Blanco telescope in Chile that collects data in 5 different wavelength ranges. It closely monitored about one eights of the total sky for a total of more than 500 nights in the years from 2013 to 2019. In the past few years, the collaboration have analysed the data and are now publishing the results.

***

"In the new data analysis they now found that the best-fit value for w is minus 0 point 8. And the 95 percent confident band is within plus 0 point 14 and minus 0 point 16 of the best fit value.

"Now remember that the simplest type of dark energy is the cosmological constant which has w equals minus 1. So the best fit is barely just outside the 95 percent confidence band. It’s a very mild tension. Kinda interesting, but too insubstantial to think much about.

***

"More interesting is that it tilts the balance against w being smaller than even minus 1. This matters because the value of w determines the ultimate fate of the universe. With w at minus 1 or larger, the universe will expand faster and faster and get darker and darker and colder and colder in a rather boring way that’s sometimes called the Big Freeze. It might also recollapse, which is called the “Big Crunch”.

"But if w was smaller, so more negative than minus one it would be much more dramatic. It’s called the “big rip”. If that happened, eventually everything in the universe would move apart from each other at almost the speed of light, and this means that no forces could hold anything together, not even elementary particles.

"The new result from the dark energy survey therefore means that a big rip is unlikely to happen, luckily. I find it kind of hard to understand what a big rip would even mean, but I’m pretty sure I don’t want to be around when it happens."

Comment: so the universe will not tear up. We'll be all gone before it might happen, so all of it is theoretical.

294 views

Had an early start:

https://bigthink.com/starts-with-a-bang/milky-way-grew-up/?utm_campaign=swab&utm_so...

"The Milky Way galaxy may be just one among trillions present within the observable Universe, but it’s uniquely special for personal reasons to us: it’s our cosmic home. It’s the fertile soil from which our Sun and Solar System, including the bodies that would eventually become planet Earth, sprung some 4.6 billion years ago. All told, it’s composed of a few hundred billion stars, about a trillion solar masses worth of dark matter, a supermassive central black hole of about 4 million solar masses, and a plethora of gas and dust. And that’s no outlier; we’re actually somewhat typical of modern galaxies, with perhaps a hundred billion others similar to our own. We’re neither among the biggest nor the smallest of galaxies, nor are we in an ultra-massive cluster or found in isolation, but rather a modest galaxy group, where we’re the second-largest member.

"Our galaxy today, in other words, is the result of 13.8 billion years of cosmic evolution, where large numbers of small proto-galaxies merged together, forming one larger-than-average galaxy, while continuously attracting additional matter into itself. We are what remains after countless other galaxies have been swallowed by our own.

***

"Galaxies, you see, don’t just grow by attracting other galaxies and merging together to form larger ones. Galaxies also experience evolution on their own, meaning that they:
rotate, form stars, funnel matter in toward the center, generate density waves along their spiral arms, attract additional matter from outside the galaxy along cosmic filaments,
and change shape and orientation based on the other galaxies and matter that falls into them.
While the earliest proto-galaxies that eventually grew into the Milky Way may have formed somewhere around 200-250 million years after the Big Bang, cosmic evolution continued all throughout that time.

***

"In some sense, we already know that our fate is sealed. The Milky Way itself is destined, approximately 4 billion years from now, to begin merging with Andromeda, and then in another 3 billion years, that merger process is expected to reach completion: resulting in a new, larger, single galaxy that already has the rather poetic name of Milkdromeda.

***

"The cosmic story that led to the Milky Way is a story of constant, but not necessarily ultra-violent, evolution. We likely formed from hundreds or even thousands of smaller, early-stage proto-galaxies and early galaxies that merged together. The spiral arms that we see today were likely formed many times by interactions, only to re-form from the rotating, gas-rich nature of an evolving, gas-rich, disk galaxy. Star formation occurred inside in waves, often triggered by minor mergers or gravitational interactions, but also occurring during quiet periods in our galaxy’s life: quiescent star formation. Finally, these waves of star-formation, as stars live-and-die, bring along increases in supernova rates, stellar cataclysms, and heavy metal enrichment of the interstellar medium.

"These changes don’t occur all-at-once and abruptly, but rather in a continuous fashion. They were not just a part of our cosmic past, but are still occurring, and will come to an extremely spectacular conclusion just a few billions of years in the future, as all the galaxies of the Local Group eventually will coalesce and merge together. Every single galaxy has its own unique cosmic story, and the Milky Way is just one typical example of a somewhat mature, larger-than-average but not among the largest galaxies, found within the Universe. What’s important to recognize is that the story hasn’t ended yet. As grown up as we are, the Milky Way, our cosmic home, is still evolving."

Comment: We live in our own home galaxy, quietly observing the vast universe around us. It all evolved from the Big Bang. I prefer to examine any process from the standpoint of purpose. Since we have evolved on Earth and are unique thinking beings, it is reasonable to conclude we were the purpose. Even if other colonies of thoughtful folks exist throughout the universe, the same conclusion applies. From a designing mind creating other minds to join with it is a reasonable conclusion.

223 views

They removed hydrogen atoms:

https://www.nature.com/articles/d41586-024-00594-8?utm_source=Live+Audience&utm_cam...

"The research, published today in Nature1, provides evidence that dwarf galaxies roughly 100 times smaller than the Milky Way triggered the process known as reionization, which changed the course of cosmic history. “The Universe became transparent,” says Hakim Atek, an astrophysicist at the Paris Institute of Astrophysics and lead author of the study. “It’s because of reionization that we are able to see distant galaxies.”

"For around 380,000 years after the Big Bang, the Universe was a hot, dense furnace of subatomic particles. As the cosmos cooled, the free electrons and protons combined to form a gas of neutral hydrogen atoms.

"What followed was a dreary period of darkness. This lasted until the gas collapsed in places to fuse and form the first stars, which produced ultraviolet (UV) light. However, the remaining gas permeating the Universe either absorbed or scattered this light. As a result, the Universe resembled a foggy forest speckled with dim, flickering fireflies, and light sources were visible only for short distances.

"To render space transparent, something needed to bombard this gas with powerful ‘ionizing’ radiation, which could transform the neutral hydrogen atoms into charged particles, or ions, of hydrogen. The three candidates were energetic light jets called quasars, which are powered by supermassive black holes; massive galaxies roughly the same size as the Milky Way; and, finally, the ‘minnows’ — dwarf galaxies.

***

"Using data gathered by the JWST, the astronomers analysed the wavelengths of UV light from these galaxies. This allowed the team to estimate that even these faint, small galaxies could have expunged hydrogen gas around them easily. The researchers also estimate that dwarf galaxies were abundant enough up to one billion years after the Big Bang to have ionized the entire Universe, even if 5% of their ionizing radiation escaped into intergalactic space.

"Small galaxies were the first to form in the Universe, which “probably makes it easier to start the [reionization] process early” in the history of the cosmos, Rhoads says. As each galaxy emitted radiation, it effectively blew a bubble of transparency that expanded into neutral gas. Eventually, all the bubbles from all the galaxies overlapped to complete the transformation.

"Dwarf galaxies would have blown bubbles smaller than those produced by quasars and massive galaxies, and such small bubbles might have ensured that reionization proceeded homogeneously across the Universe. This, in turn, had implications for the architecture of the present-day Universe, Atek says."

Comment: this helps to explain the early times after the Big Bang.

157 views

To always keep our seasons on schedule with sun's position:

https://bigthink.com/starts-with-a-bang/most-bizarre-facts-leap-day/?utm_campaign=swab&...

"without a leap day, the physics of planet Earth would quickly cause the seasons to move out of phase with our annual calendar, and the equinoxes and solstices would drift around the days, months and seasons. In fact, if we simply added a leap day to our calendars every four years without fail, things wouldn’t line up very well, either, which is precisely what happened for the centuries under which humanity followed the Julian calendar. Only if we properly account for our planet’s axial rotation and revolution around the Sun can we keep our calendar correct, and that’s what leap day is all about. Here are seven of the most bizarre, but still true, scientific facts that everyone should know.

"1.) Our calendar requires them, in part, because a “day” isn’t 24 hours long. Completing one 360° rotation is not the same as one day, as the Earth’s motion through space relative to the Sun means that rotating once on its axis actually leaves you a little bit “behind” where you needed to be.

"2.) A year is not defined by the Earth completing a revolution around the Sun. This means that by the time one sidereal year (a complete 360° revolution of Earth around the Sun) has passed, the Earth is now oriented slightly differently with respect to the Sun versus how its axis was pointed the sidereal year prior. Instead of a sidereal year, our calendar needs to be based on the tropical year, which differs from a sidereal year by about 20 minutes, with the tropical year being slightly shorter than a sidereal year. In other words, the day and the year both are not defined simply by a constant celestial motion, but also by changes, as the Earth-Sun distance and the relative Earth-Sun orientation are inconstant.

"3.) There aren’t an even number of days in the year, no matter how you measure it. You’ll find that there are 365.242188931 days in a true calendar year, to the best currently-known precision.

"4.) Our current, Gregorian calendar, complete with its prescription for leap days, isn’t quite perfect either. Under the Gregorian calendar, if your year ends in the numbers “00,” as in you’re experiencing the turn of the century, it’s only a leap year if that number is also divisible by 400. In other words, 2000 was a leap year, as was 1600 and as 2400 will be, but 1700, 1800, and 1900 weren’t, and 2100, 2200, and 2300 won’t be, either...Instead of 365.25 days in a year, which the Julian calendar gave us on average, the Gregorian calendar then gives us 365.2425 days in a year, which is much closer to the actual number of days we experience in a year. In fact, whereas the Julian calendar drifted by about a day with each 150 years that went by, the Gregorian calendar won’t drift by a full day until around 3200 years pass.

"5.) Earth’s orbit actually is changing, which means our current system of leap days will need to be revised down the road. Our moon doesn’t just exert a gravitational pull on the Earth, it pulls ever so slightly more on the part of Earth that’s closer to it than the part that’s in the center, and pulls even less on the part that’s farther away.

This creates a tidal bulge on the Earth, and as the Earth spins and the moon orbits around the Earth, those tidal forces from the moon cause two very small changes that occur together.

Earth’s rotation rate, ever so slightly, slows down. it turns out that this effect — known as tidal braking — causes Earth’s rotation rate to slow down by about 14 microseconds per year. This means that, even now, Earth’s Day is getting slightly longer. As time marches onward, we’ll need to add fewer and fewer leap days to keep our calendar in sync.

"6.) In about 4 million years, leap days will be unnecessary, and the calendar will contain exactly 365 days for a time. Tidal braking might be almost imperceptible on human timescales, but its effects — very importantly — are cumulative, meaning that they add up over time.

"7.) The long-term changes in leap days coincide with the loss of total solar eclipses. It’s difficult to believe, but the same tidal braking from our moon that causes Earth’s rate of rotation to gradually slow causes the moon to spiral away from the Earth: it’s a consequence of the law of conservation of angular momentum. Both “spinning” and “orbiting” are types of angular momentum, and as the Earth’s spin slows down owing to the moon’s tidal forces, it gets transferred in a fashion that increases the Earth-moon distance.

***

"For now, however, this leap year means we simply get an extra day for 2024, and that when 2096 rolls around, we’ll have enjoyed a long streak of every 4th year being a leap year since 1904. However, 1900 wasn’t a leap year and 2100 won’t be either, so to those of you with February 29th birthdays — an estimated 5.5 million of you — enjoy celebrating your special day once every four years until then. After that, you’ll have to wait for eight of them to go by between 2096 and 2104!"

Comment: quite a complicated mess, but not to worry. Each year buy a new calendar and you will be OK. Just remember Homo sapiens evolved on time, wherever it was on the measure of days of the year.

151 views

An x-ray study of the universe:

https://www.quantamagazine.org/fresh-x-rays-reveal-a-universe-as-clumpy-as-cosmology-pr...

"Clusters of hundreds or thousands of galaxies sit at the intersections of giant, crisscrossing filaments of matter that form the tapestry of the cosmos. As gravity pulls everything in each galaxy cluster toward its center, the gas that fills the space between the galaxies gets compressed, causing it to heat up and glow in X-rays.

"The eRosita X-ray telescope, lofted into space in 2019, spent more than two years collecting pings of high-energy light from all over the sky. The data has allowed scientists to map the locations and sizes of thousands of galaxy clusters, two-thirds of them previously unknown. In a slew of papers posted online on February 14 that will appear in the journal Astronomy & Astrophysics, the scientists used their initial catalog of clusters to weigh in on several of cosmology’s big questions.

"The results include new estimates of the clumpiness of the cosmos — a much-discussed characteristic of late, as other recent measurements have found it to be unexpectedly smooth — and of the masses of ghostlike particles called neutrinos and of a key property of dark energy, the mysterious repulsive energy that’s speeding up the universe’s expansion.

***

"The eRosita observations...bolster the existing picture on all counts. “It’s a remarkable confirmation of the standard model,” said Dragan Huterer, a cosmologist at the University of Michigan who was not involved in the work.

***

"One number of interest is the “clumpiness factor” of the universe, S8. An S8 value of zero would represent a vast cosmic nothingness, akin to a flat plain with nary a rock in sight. An S8 value closer to 1 corresponds to steep mountains looming over deep valleys. Scientists have estimated S8 based on measurements of the cosmic microwave background (CMB) — ancient light coming from the early universe. Extrapolating from the cosmos’s initial density variations, researchers expect the current S8 value to be 0.83.

***

“'Our result was basically in line with the prediction from the very early time, from the CMB,” said Vittorio Ghirardini, who led the analysis. He and his colleagues calculated an S8 of 0.85.

***

"From their map of thousands of clusters, the researchers found that dark energy matches the profile of a cosmological constant, although their measurement has a 10% uncertainty, so an ever-so-slightly varying dark energy density remains possible.

***

"These initial papers draw from just the first six months of data. The German group expects to find about four times as many galaxy clusters in the additional 1.5 years of observations, which will allow all these cosmological parameters to be pinpointed with more accuracy. “Cluster cosmology could be the most sensitive probe of cosmology other than the CMB,” said Anja von der Linden, an astrophysicist at Stony Brook University."

Comment: the history of the universe since the Big Bang is quite clear and this article gives it more support.

149 views

Another nail in the coffin:

https://mail.google.com/mail/u/0/#inbox/FMfcgzGxSHcKDFJSCffvfBrCJgWTFtFC

"It was a beautiful idea, no doubt, and thousands of physicists spent decades on it. But it didn’t quite go according to plan. String theory became extremely controversial about 20 years ago during a phase that’s been dubbed the “String Wars”. Then it kind of fizzled out. What happened? What were the string wars? And what are string theorists doing now?

***

"After the completion of the standard model, string theory swiftly became the hottest contender for this theory of everything.

***

'This version of string theory still exists today as a bottom-up approach to understand what gluons do, but the string theory that we are concerned with is a different one. You see, when physicists studied what those strings do, they found that some of them behave like a graviton, that’s a quantum of the gravitational interaction.

"It’s a particle which has never been observed, not then and not now, but that could be the start of giving quantum properties to gravity. At the same time, strings were so versatile that they could also behave like particles that make up matter and those who make up light. Strings could do all of it. It was what they’d been looking for – a theory of everything.

***

"Plausible enough you might say, but even so, supersymmetry predicted something else, a type of process that can’t happen in the standard model. It involves what’s known flavour-changing neutral currents. Evidence for those processes should have shown up in the early 1990s at the Large Electron Positron collider at CERN. It did not. And so, string theorists added another fix to their theory, R-symmetry, to make their equations agree with observations again.

"Then there was the problem that string theory required a total of 10 dimensions of space to properly work. Unfortunately, it seems that the space we find ourselves in has merely 3 dimensions. String theorists explained away the extra dimensions of space by saying they are rolled up to sizes so small that we can’t see them. Again this works because measuring something small requires a lot of energy, and we might not have noticed these small dimensions because we haven’t been able to achieve particle collisions with sufficiently high energy.

"Now when I say they rolled up those extra dimensions that might suggest each of them is like a straw and there’s only one way to do it. But actually there are many different ways to do it. Already in two dimensions you have a torus or a sphere as example. And if you have 6 dimensions there’s a huge number of ways to roll these dimensions up, some hundred thousand or so. At this point, the idea that string theory was unique and would just spit out the standard model went out of the window.

"The problems did not stop there. String theory works best in a universe with a negative cosmological constant and string theorists originally just assumed that’d be so. The cosmological constant, if you remember, is a constant of nature that determines how the expansion of the universe changes, whether it gets faster or slower. The expansion of our universe gets faster, and that means the cosmological constant is positive, exactly the opposite of what string theory requires.

***

"But all this paper writing didn’t help string theorists find that theory of everything they’d been looking for. There were just too many versions of string theory now, an estimated 10 to the 500. And since they couldn’t find one that actually reproduced the standard model and general relativity, they postulated all of them exist. This is the so-called string theory landscape.

I’ve always found that to be a particularly idiotic move. Just because you can’t figure out which theory describes reality doesn’t mean all of them are real. And in any case, it didn’t solve any problem because they did, as a matter of fact, not have the theory they were looking for.

***

"I wasn’t the only one back then who had the feeling that something was going badly wrong in the foundations of physics. In 2006, two books appeared almost simultaneously, taking issue with string theory. One was Lee Smolin’s “The trouble with physics”, the other Peter Woit’s “Not Even Wrong”.

***

"in 2010 the LHC turned on, didn’t find any evidence for supersymmetry or extra dimensions or string balls or gravitons or what have you, and the bubble in which string theory had been testable burst.

***

"In summary. String theory had a really good motivation, and it was pursued as a theory of everything for good reasons. However, when that didn’t work out, string theorists were slow to get the message and a lot of time and effort was wasted on it. It’s not that string theory turned out to be completely useless. Some techniques have survived and are being used today in related areas of physics."

Comment: Long ago I quoted Peter Woit here with the same conclusions. Shows we stay up to date.

135 views

A gravitational pull every 2.4 million years:

https://www.livescience.com/planet-earth/rivers-oceans/every-24-million-years-mars-tugs...

Geological evidence tracing back more than 65 million years and taken from hundreds of sites across the world suggests that deep-sea currents have repeatedly gone through periods of being either stronger or weaker. This happens every 2.4 million years and is known as an "astronomical grand cycle."

The stronger currents, known as "giant whirlpools" or eddies, may reach the seafloor at the deepest parts of the ocean, known as the abyss. These powerful currents then erode away at the large pieces of sediment that accumulate during calmer periods in the cycle, according to research published...in the journal Nature Communications.

These cycles happen to coincide with the timing of known gravitational interactions between Earth and Mars as the two planets orbit the sun, the study found.

"The gravity fields of the planets in the solar system interfere with each other and this interaction, called a resonance, changes planetary eccentricity, a measure of how close to circular their orbits are," study co-author Dietmar Müller, a professor of geophysics at the University of Sydney, said.

Due to this resonance, the Earth is pulled slightly closer to the sun by Mars' gravitational pull, meaning our planet is exposed to more solar radiation and hence has a warmer climate, before drifting backward again — all over a period of 2.4 million years.

***

Nevertheless, although speculative at this stage, the findings suggest that this cycle may help periodically maintain some of the ocean's deep currents in the event that global warming decreases them, the authors say.

"We know there are at least two separate mechanisms that contribute to the vigor of deep-water mixing in the oceans," Müller said. One of these mechanisms is known as the Atlantic Meridional Overturning Circulation (AMOC), Müller said. This acts as an ocean "conveyor belt," bringing warm water from the tropics to the Northern Hemisphere, pulling heat deep into the ocean in the process.

Comment: this is an interesting interaction between planets. Yet, as noted, over millions of years all stays in balance.

119 views

Supermassive but quiet:

https://mail.google.com/mail/u/0/#inbox/FMfcgzGxSRGfRtccszfDDBnRbgNTFRph

"...unlike its ferocious cousins in distant galaxies that actively gobble up surrounding material, A* turns out to be a very picky eater.

"And that’s the first reason our black hole is weird: Most of the time, it appears relatively calm, emitting faint radiation and consuming matter at a slow pace. The next reason it’s weird is that while normally very quiet, A* periodically flares up with brief bright infrared and X-ray flares. Just why it does that has so far remained a mystery.

***

"A third reason is that in in 2019 Sagittarius A* it surprised astronomers by a sudden increase in activity, pulling in a much larger amount of dust and gas which no one saw coming.

"A fourth observation that adds to the mystery are the G-objects that orbit A*, where the G stands for gas, though astrophysicists now believe they are a mix of gas and dust. The first such object was discovered in 2004 was called G1, followed by G2 in 2012. By now astronomers have seen about a dozen of them.

"They have elongated shapes and peculiar orbits that bring them close to the event horizon and yet some of them survive mostly intact and escape. Their total mass is probably a few to a few dozen times the mass of Earth. However, it’s unclear exactly what they’re made of, where they come from, or how about how they manage to survive for that long the harsh environment so close to the black hole.

"The fifth reason our black hole is weird is its spin. In a paper that just appeared a few months ago, a study from researchers at Penn State used x-ray data from the Chandra Observatory and radio data from the Very Large Array. They found that Sagittarius A* is spinning almost at the theoretical limit, at 60% of what’s possible. You see black holes can’t spin arbitrarily fast because at some point that would exceed the speed of light limit. The 60% is so fast that it significantly pull spacetime with it as it spins. It goes around about once every 10 minutes.

"The sixth and final reason why our black hole is weird is the blob. A team of astrophysicists at the National Autonomous University of Mexico recently discovered a strange object, a blob of gas whipping around the black hole at an astonishing 30% the speed of light!

"They spotted this object by analysing data collected by the Fermi Gamma-ray Space Telescope. This speeding blob releases powerful bursts of gamma rays, a form of high-energy radiation, every 76 minutes. The scientists say that this discovery could be the key to understanding where the strange gamma-ray blasts come from.

Comment: this is not so mysterious if you accept a designer God who put life on Earth and wanted it protected from a dangerous black hole.

96 views

More discoveries about the ancient beginning of the Milky way:

https://www.sciencealert.com/these-ancient-rivers-of-stars-have-flowed-since-the-milky-...

"Relics of the Milky Way's birth have just been discovered hiding in plain sight.

"Towards the center of the galaxy, two streams of stars nearly as old as the Universe have been discovered circling the heart of the Milky Way. A new analysis based on data from the European Space Agency's Gaia telescope strongly suggests that these ancient streams existed before the Milky Way even had its spiral arms – when it was just a baby galaxy extending its first tendrils of stars out into the space around it.

"These two streams, discovered by astrophysicist Khyati Malhan and astronomer Hans Walter-Rix of the Max Planck Institute for Astronomy in Germany, have been named Shiva and Shakti after the creators of the Universe in Hindu mythology.

***

"The Milky Way is thought to have started forming some 13 billion years ago, when the Universe was freshly minted and forging its first stars and galaxies at a tremendous rate. Piecing together that history is a field known as galactic archaeology, and it relies in part on finding populations of stars whose properties are consistent with an ancient origin.

"This is where the work being performed by Gaia is so valuable. The space telescope is mapping the Milky Way with the highest precision yet, collecting data on the 3D positions of the galaxy's stars, their velocity, and their proper motions. It also measures a property known as the metallicity of a star – that is, metallic elements in its composition.

"Since most metals simply weren't around before stars and novae came along and generated them, the metallicity of a star can give us some idea of how old a star is. The more metal content a star has, the younger it probably is.

"Using this information in conjunction with the Gaia data, astronomers can identify groups of stars that we might not otherwise detect. If a group of stars is in the same place in space, moves through the galaxy in the same way, and has similar metallic properties, that means those stars probably belong to the same specific group.

"Moreover, these structures can be used to determine the history of the Milky Way. Some stellar streams, for instance, can be traced to disrupted clusters of stars. Others are the remnants of other galaxies that fell into and were torn apart by the gravity of the Milky Way.

"This is how Malhan and Walter-Rix identified Shiva and Shakti. They used Gaia to perform galactic archaeology on regions closer towards the heart of the Milky Way in 2022, and identified therein a population of very old, very metal-poor stars. But they noticed two distinct streams with stars of a similar age – around 12 to 13 billion years old – a little farther out from the center.

***

"Each stream has a mass of around 10 million Suns, orbiting in the same direction as the rotation of the Milky Way. Shiva is closer to the galactic center with more elliptical orbits; Shakti is a little farther out, but its stars trace more circular paths around the galactic center.

"Their structures, the researchers found, suggest that the two streams each formed as a distinct structure that then merged with the Milky Way spiral as it was forming, feeding its growth. The pair believes that the galaxy formed from a blob that grew as filaments and tendrils of stars from the surrounding space fell onto and wrapped around it, forming stars. Shiva and Shakti appear to be two of these filaments."

Comment: I'm certain other spiral galaxies had the same history.

91 views

Helped form heavier elements:

https://phys.org/news/2024-03-gravitational-human-life.html

"Could it be that human existence depends on gravitational waves? Some key elements in our biological makeup may come from astrophysical events that occur because gravitational waves exist, a research team headed by John R. Ellis of Kings College London suggests.

"In particular, iodine and bromine are found on Earth thanks to a particular nuclear process that happens when neutron stars collide. In turn, orbiting neutron star pairs inspiral and collide due to their emissions of energy in the form of gravitational waves. There may thus be a direct path from the existence of gravitational waves to the existence of mammals.

"Humans are mostly made up of hydrogen, carbon and oxygen, with many additional trace elements. (There are 20 elements essential to human life.) Those with an atomic number less than 35 are produced in supernovae, implosions of stars that have exhausted their nuclear fuel and collapsed inward. The collapse results in an explosion that spews their atoms all over the universe.

"But two elements are provided by other means—iodine, needed in key hormones produced by the thyroid, and bromine, used to create collagen scaffolds in tissue development and architecture.

"Thorium and uranium have been indirectly important for human life, as their radioactive decays in Earth's interior heat the lithosphere and allow tectonic activity. The movement of tectonic plates removes and submerges carbon from the crust of the planet, which is itself removed from the atmosphere via water reacting with carbon dioxide and silicates, avoiding the possibility of a runaway greenhouse effect like has happened on Venus.

"About half the heavy elemental atoms on Earth (heavier than iron) are produced by what's known as the "r-process"—the rapid neutron-capture process. The r-process occurs when a heavy atomic nucleus captures a succession of free neutrons before the nucleus has had a chance to decay (usually by beta decay).

"With a high enough density of free neutrons, calculated to be about 1024 per cubic centimeter, and at high temperatures, around a billion Kelvin, neutrons are absorbed and heavier isotopes of an element are synthesized.

"Ellis and his colleagues calculate that the r-process has provided 96% of the abundance of 127I on Earth, an isotope essential for human life, and most of the abundance of bromine and gadolinium in the Earth's crust, plus all of the Earth's thorium and uranium and a fraction of the molybdenum and cadmium.

"Where does the r-process occur? One possibility is the material ejected during the rebound from a core-collapse supernova, the explosions of stars near the end of their thermonuclear lifetimes. But there is long-standing uncertainty in the detailed physics of this process.

"One phenomenon where the r-process does occur is the merger of two neutron stars, called a kilonova. Such mergers are directly caused by gravitational waves.

***

"Kilonovae outbursts are important sites of the r-process, as neutron stars are made almost entirely of neutrons. Besides the gravitational wave observatories, other detectors detected GW170817 in the electromagnetic spectrum, and found spectroscopic evidence of the material created and tossed out from the merger.

"The paper concludes that the iodine essential for human life was "probably produced by the r-process in the collisions of neutron stars that were induced by the emissions of gravitational waves, as well as other essential heavy elements." The group suggests searching for 129I in lunar regolith, which is uncontaminated by manmade sources.

"'Neutron star collisions occur because binary systems lose energy by emitting gravitational waves," said Ellis, "so these fundamental physics phenomena may have made human life possible.'"

Comment: what this article describes is a series of contingent events to allow us to arrive. Gould made a great fuss about the importance of contingency. Think about it. The events, theorized in this article to have happened, are so highly improbable, how did such a series of them happen? Back we go to design planning.

82 views

One year in operation:

https://www.symmetrymagazine.org/article/first-results-from-desi-make-the-most-precise-...

"With 5,000 tiny robots in a mountaintop telescope, researchers can look 11 billion years into the past. The light from far-flung objects in space is just now reaching the Dark Energy Spectroscopic Instrument, enabling us to map our cosmos as it was in its youth and trace its growth to what we see today. Understanding how our universe has evolved is tied to how it ends, and to one of the biggest mysteries in physics: dark energy, the unknown ingredient causing our universe to expand faster and faster.

"To study dark energy’s effects over the past 11 billion years, DESI has created the largest 3D map of our cosmos ever constructed, with the most precise measurements to date. This is the first time scientists have measured the expansion history of the young universe with a precision better than 1%, giving us our best view yet of how the universe evolved.

***

"Our leading model of the universe is known as Lambda CDM. It includes both a weakly interacting type of matter (cold dark matter, or CDM) and dark energy (Lambda). Both matter and dark energy shape how the universe expands—but in opposing ways. Matter and dark matter slow the expansion down, while dark energy speeds it up. The amount of each influences how our universe evolves. Lambda CDM does a good job of describing results from previous experiments and how the universe looks throughout time.

"However, when DESI’s first-year results are combined with data from other studies, there are some subtle differences with what Lambda CDM would predict. As DESI gathers more information during its five-year survey, these early results will become more precise, shedding light on whether the data are pointing to different explanations for the results we observe or to the need to update our model. More data will also improve DESI’s other early results, which weigh in on the Hubble constant (a measure of how fast the universe is expanding today) and the mass of particles called neutrinos.

***

"Looking at DESI’s map, it’s easy to see the underlying structure of the universe: strands of galaxies clustered together, separated by voids with fewer objects. Our very early universe, well beyond DESI’s view, was quite different: a hot, dense soup of subatomic particles moving too fast to form stable matter like the atoms we know today. Among those particles were hydrogen and helium nuclei, collectively called baryons.

"Tiny fluctuations in this early ionized plasma caused pressure waves, moving the baryons into a pattern of ripples that is similar to what you’d see if you tossed a handful of gravel into a pond. As the universe expanded and cooled, neutral atoms formed and the pressure waves stopped, freezing the ripples in three dimensions and increasing clustering of future galaxies in the dense areas. Billions of years later, we can still see this faint pattern of 3D ripples, or bubbles, in the characteristic separation of galaxies—a feature called Baryon Acoustic Oscillations.

***

“'We’ve measured the expansion history over this huge range of cosmic time with a precision that surpasses all of the previous BAO surveys combined,” says Hee-Jong Seo, a professor at Ohio University and the co-leader of DESI’s BAO analysis. “We're very excited to learn how these new measurements will improve and alter our understanding of the cosmos. Humans have a timeless fascination with our universe, wanting to know both what it is made of and what will happen to it.”

***

"Researchers used 450,000 quasars, the largest set ever collected for these Lyman-alpha forest measurements, to extend their BAO measurements all the way out to 11 billion years in the past. By the end of the survey, DESI plans to map 3 million quasars and 37 million galaxies.

***

"DESI’s data will be used to complement future sky surveys such as the Vera C. Rubin Observatory and Nancy Grace Roman Space Telescope, and to prepare for a potential upgrade to DESI (DESI-II) that was recommended in a recent report by the US Particle Physics Project Prioritization Panel.

“'We are in the golden era of cosmology, with large-scale surveys ongoing and about to be started, and new techniques being developed to make the best use of these datasets,” says Arnaud de Mattia, a researcher with the French Alternative Energies and Atomic Energy Commission and co-leader of DESI’s group interpreting the cosmological data."

Comment: from our tiny cubbyhole in the universe human ingenuity is allowing us to explore all of it. This first year of results validates its usefulness. One instance where your taxes are reasonably used. Perhaps we will learn why God had to make it so big.

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A huge black hole with high-speed stars in all sorts of wild orbits:

https://www.sciencealert.com/mysterious-stars-at-the-heart-of-the-milky-way-hide-a-dark...

"A study of the stars crashing around in the Milky Way's galactic center suggests that they are much, much older than they appear – and that their youthful good looks are the result of cosmic cannibalism.

"'A few stars win the collision lottery," says astrophysicist Sanaea Rose of Northwestern University in Illinois.

"'Through collisions and mergers, these stars collect more hydrogen. Although they were formed from an older population, they masquerade as rejuvenated, young-looking stars. They are like zombie stars; they eat their neighbors."

"The galactic center is a hectic place. To start with, there is a chonkin' great supermassive black hole there, some 4 million times the mass of the Sun. Around it, stars whirl and whiz, reaching absolutely insane speeds on their long, looping orbits. And there are a lot of them. The galactic center is positively jostling with stars, the Milky Way's densely crowded hub.

:It's an environment that's primed for star-on-star crime.

***

"Studying the stars in the galactic center directly is pretty tricky, because there's a lot of stuff in there, including dense clouds that obscure the view in most wavelengths. Rose and her colleagues turned to simulations, creating a model of the galactic center and everything within it, and watching the outcomes once the stars are set in motion.

"They found that the fate of colliding stars appears to be directly linked to proximity to the black hole. Within 0.01 parsecs – about one-thirtieth of a light-year – interactions between stars are par for the course, but because of their high speeds, they tend to survive. Interactions tend to be grazing collisions that leave both stars more or less intact, although they may lose a fair bit of their outer material in the process.

"Outside of that 0.01-parsec boundary, though, things get a little more violent. Because the stars are moving much more slowly, they don't have the angular momentum to keep going when they encounter each other. Instead, they become snared in each other's gravity, resulting in a full collision that sees the stars moosh together to become one big star.

"And it's in this process that some stars gain enough hydrogen to give them a more youthful appearance, even though they may be quite a bit older. But there's a trade-off. The more massive a star is, the shorter its lifespan.

"'Massive stars are sort of like giant, gas-guzzling cars," Rose explains. "They start with a lot of hydrogen, but they burn through it very, very fast."

"...the findings do explain a curious feature of the star population in the galactic center: a puzzling absence of old red giant stars. Both mass loss from grazing collisions and mergers that create larger, short-lived stars would reduce the number of red giants you'd expect to see in a normal star population, the researchers found."

Comment: by design the Earth is safely far away, two-thirds of the way out on the second spiral arm. It seems the larger the galaxy, the more turbulent is its center.

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Not what theory predicts:

https://www.amazon.com/Bed-Wedge-Pillow-Adjustable-Combination/dp/B08N42364Y/ref=sr_1_3...

"There is a significant discrepancy between theoretical and observed amounts of lithium in our universe. This is known as the cosmological lithium problem, and it has plagued cosmologists for decades. Now, researchers have reduced this discrepancy by around 10%, thanks to a new experiment on the nuclear processes responsible for the creation of lithium. This research could point the way to a more complete understanding of the early universe.

:There is a famous saying that, "In theory, theory and practice are the same. In practice, they are not." This holds true in every academic domain, but it's especially common in cosmology, the study of the entire universe, where what we think we should see and what we really see doesn't always match up. This is largely because many cosmological phenomena are difficult to study due to inaccessibility.

***

"In a nutshell, theory predicts that in the minutes following the big bang that created all matter in the cosmos, there should be an abundance of lithium around three times greater than what we actually observe.

"But Hayakawa and his team accounted for some of this discrepancy and have thus paved the way for research that may one day resolve it entirely.

"13.7 billion years ago, as matter coalesced from the energy of the big bang, common light elements we all recognize -- hydrogen, helium, lithium and beryllium -- formed in a process we call Big Bang nucleosynthesis (BBN)," said Hayakawa.

"'However, BBN is not a straightforward chain of events where one thing becomes another in sequence; it is actually a complex web of processes where a jumble of protons and neutrons builds up atomic nuclei, and some of these decay into other nuclei. For example, the abundance of one form of lithium, or isotope -- lithium-7 -- mostly results from the production and decay of beryllium-7. But it has either been overestimated in theory, underobserved in reality, or a combination of the two. This needs to be resolved in order to really understand what took place way back then."

***

"However, even though the accepted models of BBN predict the relative amounts of all elements involved in BBN with extreme accuracy, the expected amount of lithium-7 is around three times greater than what is actually observed.

"This means there is a gap in our knowledge about the formation of the early universe.

***

"'We scrutinized more than ever before one of the BBN reactions, where beryllium-7 and a neutron decay into lithium-7 and a proton. The resulting levels of lithium-7 abundance were slightly lower than anticipated, about 10% lower," said Hayakawa. "This is a very difficult reaction to observe since beryllium-7 and neutrons are unstable. So we used deuteron, a hydrogen nucleus with an extra neutron, as a vessel to smuggle a neutron into a beryllium-7 beam without disturbing it. This is a unique technique, developed by an Italian group we collaborate with, in which the deuteron is like the Trojan horse in Greek myth, and the neutron is the soldier who sneaks into the impregnable city of Troy without tipping off the guards (destabilizing the sample). Thanks to the new experimental result, we can offer future theoretical researchers a slightly less daunting task when trying to resolve the CLP."

Comment: what God produces is usually so straight forward we can figure out all of it. Sometimes the complexity, as in this case, needs special techniques. But humans are up to it.

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Weighing the Milky Way by comparative galaxy gravitational estimates:-http://www.sciencedaily.com/releases/2014/07/140729224959.htm

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