Cosmology; Does electromagnetism vary across the universe (Introduction)
by David Turell 
, Tuesday, November 01, 2011, 00:46 (4772 days ago)
Perhaps. The implications:
http://www.physorg.com/news/2011-10-nature-laws-vary-universe.html
Cosmology; Does electromagnetism vary across the universe
by David Turell , Saturday, February 10, 2018, 01:22 (2479 days ago) @ David Turell
The universe is filled with magnetic fields. The cause is now clarified:
https://phys.org/news/2018-02-astrophysicists-cosmic-debate-magnetism-planets.html
"The universe is highly magnetic, with everything from stars to planets to galaxies producing their own magnetic fields. Astrophysicists have long puzzled over these surprisingly strong and long-lived fields, with theories and simulations seeking a mechanism that explains their generation.
"...a team led by University of Chicago scientists experimentally confirmed one of the most popular theories for cosmic magnetic field generation: the turbulent dynamo. By creating a hot turbulent plasma the size of a penny, that lasts a few billionths of a second, the researchers recorded how the turbulent motions can amplify a weak magnetic field to the strengths of those observed in our sun, distant stars, and galaxies.
***
"Confirming decades of numerical simulations, the experiment revealed that turbulent plasma could dramatically boost a weak magnetic field up to the magnitude observed by astronomers in stars and galaxies.
"'We now know for sure that turbulent dynamo exists, and that it's one of the mechanisms that can actually explain magnetization of the universe," said Petros Tzeferacos, research assistant professor of astronomy and astrophysics and associate director of the Flash Center. "This is something that we hoped we knew, but now we do."
"A mechanical dynamo produces an electric current by rotating coils through a magnetic field. In astrophysics, dynamo theory proposes the reverse: the motion of electrically-conducting fluid creates and maintains a magnetic field. In the early 20th century, physicist Joseph Larmor proposed that such a mechanism could explain the magnetism of the Earth and Sun, inspiring decades of scientific debate and inquiry.
***
"The team also used FLASH simulations to develop two independent methods for measuring the magnetic field produced by the plasma: proton radiography, the subject of a recent paper from the FLASH group, and polarized light, based on how astronomers measure the magnetic fields of distant objects. Both measurements tracked the growth in mere nanoseconds of the magnetic field from its weak initial state to over 100 kiloGauss—stronger than a high-resolution MRI scanner and a million times stronger than the magnetic field of the Earth.
"'This work opens up the opportunity to verify experimentally ideas and concepts about the origin of magnetic fields in the universe that have been proposed and studied theoretically over the better part of a century," said Fausto Cattaneo, Professor of Astronomy and Astrophysics at the University of Chicago and a co-author of the paper."
Comment: There have been comments about an electromagnetic universe fields in previous dicussions, and we certainly need to learn more about them, as electromagnetism in one of the four basic forces of the universe.
Cosmology; detection of first light
by David Turell , Saturday, March 03, 2018, 18:42 (2457 days ago) @ David Turell
Light in the initial darkness came (by theory) with the first stars:
https://cosmosmagazine.com/space/first-light-the-signature-of-the-earliest-stars-detected
"The traces of the first daybreak in the universe have been detected by a small radio-telescope in Western Australia.
"Astronomers know that shortly after the Big Bang, 13.7 billion years ago, everything was dark. After its intensely energetic burst of expansion, the universe cooled. Gradually, in the ensuing eons, gravity pulled bits of matter together into clumps, then into larger bodies, until finally, around 180 million years after the process began, a critical mass was reached and the first stars ignited.
"As the light interacted with hydrogen gas, a signal was created. That signal has now been finally detected by a collaboration between Australian research organisation, the CSIRO, and Arizona State University in the US.
"The accepted models for predicting events in the very early universe suggest that when ultraviolet light produced by the first stars interacted with hydrogen gas, it would change how the gas absorbs radiation. This change was expected to show up as a dip in radiowaves coming from space at frequencies lower than 200 megahertz.
"In a paper published in the journal Nature, scientists led by Judd Bowman of Arizona State report the detection of such a dip around 78 megahertz, with a profile “largely consistent with expectations” for signals produced by early stars.
"There are, however, some significant differences between it and the predictions, Mainly, Bowman and colleagues reveal the amplitude of the signal is twice as strong as suggested in even the uppermost estimates.
"This, they write, may be because the primordial hydrogen was colder than expected, or the radiation temperature was hotter. The scientists suggest the best-fit explanation is cooling caused by interactions between dark matter and subatomic particles.
***
“'This is one of the most technically challenging radio astronomy experiments ever attempted,” says MRO manager Antony Schinckel.
“'The lead authors include two of the best radio astronomy experimentalists in the world and they have gone to great lengths to design and calibrate their equipment in order to have convincing evidence for a real signal.”
"Schinckel describes the result as “an absolute triumph”.
"Other scientists have been equally effusive.
“'The apparent detection of the signature of the first stars in the universe will be a revolutionary discovery if it stands the tests of time,” says astrophysicist and Nobel laureate Brian Schmidt.
“'While the detection appears robust, it is an incredibly challenging measurement, and needs to be confirmed. The fact that the detection is much stronger than expected, and that can be easily explained, is particularly exciting.”
***
"If the signal is confirmed by other experiments (which may happen soon),” he adds, “the implications for our understanding of the evolution of the universe and the nature of cosmic dark matter will be profound.'”
Comment: It is truly amazing how much can be predicted from the dawn of the universe deduced from observations made and understood today.
Cosmology; Hawking's theory of a beginning
by David Turell , Saturday, March 03, 2018, 18:57 (2457 days ago) @ David Turell
Basically there is no 'before' before the Big Bang. This is a 15+ year old theory championed by Alan Guth et. al.:
https://www.livescience.com/61914-stephen-hawking-neil-degrasse-tyson-beginning-of-time...
"Hawking's answer to the question "What was there before there was anything?" relies on a theory known as the "no-boundary proposal.
***
"As scientists know now, the universe is constantly expanding. As you move backward in time, then, the universe contracts. Rewind far enough (about 13.8 billion years), and the entire universe shrinks to the size of a single atom, Hawking said.
"This subatomic ball of everything is known as the singularity (not to be confused with the technological singularity during which artificial intelligence will overtake humans). Inside this extremely small, massively dense speck of heat and energy, the laws of physics and time as we know them cease to function. Put another way, time as we understand it literally did not exist before the universe started to expand. Rather, the arrow of time shrinks infinitely as the universe becomes smaller and smaller, never reaching a clear starting point.
"According to TechTimes, Hawking says during the show that before the Big Bang, time was bent — "It was always reaching closer to nothing but didn't become nothing," according to the article. Essentially, "there was never a Big Bang that produced something from nothing. It just seemed that way from mankind's point of perspective."
"In in a lecture on the no-boundary proposal, Hawking wrote: "Events before the Big Bang are simply not defined, because there's no way one could measure what happened at them. Since events before the Big Bang have no observational consequences, one may as well cut them out of the theory, and say that time began at the Big Bang." (my bold)
"This isn't the first time Hawking has discussed this theory. He previously delivered lectures on the topic and starred in a free documentary about it, available on YouTube.
Comment: If time began at the Big Bang (that is the time of our reality) it looks like a creation to us. Of course, scientists can't bring in God as creator, but it is a piece of the evidence for God.
Cosmology; Hawking's theory of a beginning
"In a lecture on the no-boundary proposal, Hawking wrote: "Events before the Big Bang are simply not defined, because there's no way one could measure what happened at them. Since events before the Big Bang have no observational consequences, one may as well cut them out of the theory, and say that time began at the Big Bang." (David's bold)
DAVID’s comment: If time began at the Big Bang (that is the time of our reality) it looks like a creation to us. Of course, scientists can't bring in God as creator, but it is a piece of the evidence for God.
Time is whatever you define it to be. I define it as a sequence of before-now-after. The fact that we can't observe the consequences of events before the BB (if it happened) does not mean there was no before, i.e. no cause, cause of the cause etc. You and I would agree on that, I think. Presumably, since he is an atheist, Hawking is convinced there is no point in considering any theory that cannot be verified by observation, because the universe consists only of its materials. That should be anathema to you, so I don't quite know why you're quoting him with such boldness. As for evidence, however, the Big Bang (if it happened) is no more evidence for a God than it is for chance, though no doubt you and Hawking would disagree - you one way and he the other.
Cosmology; Hawking's theory of a beginning
by David Turell , Sunday, March 04, 2018, 15:14 (2457 days ago) @ dhw
"In a lecture on the no-boundary proposal, Hawking wrote: "Events before the Big Bang are simply not defined, because there's no way one could measure what happened at them. Since events before the Big Bang have no observational consequences, one may as well cut them out of the theory, and say that time began at the Big Bang." (David's bold)
DAVID’s comment: If time began at the Big Bang (that is the time of our reality) it looks like a creation to us. Of course, scientists can't bring in God as creator, but it is a piece of the evidence for God.
dhw: Time is whatever you define it to be. I define it as a sequence of before-now-after. The fact that we can't observe the consequences of events before the BB (if it happened) does not mean there was no before, i.e. no cause, cause of the cause etc. You and I would agree on that, I think. Presumably, since he is an atheist, Hawking is convinced there is no point in considering any theory that cannot be verified by observation, because the universe consists only of its materials. That should be anathema to you, so I don't quite know why you're quoting him with such boldness. As for evidence, however, the Big Bang (if it happened) is no more evidence for a God than it is for chance, though no doubt you and Hawking would disagree - you one way and he the other.
I am quoting him because the 'no boundaries' proposal specifically says there is no 'before' before the Big Bang. It specifically implies a creation of some sort. Naturally I choose God.
Cosmology; Hawking's theory of a beginning
DAVID’s comment: If time began at the Big Bang (that is the time of our reality) it looks like a creation to us. Of course, scientists can't bring in God as creator, but it is a piece of the evidence for God.
dhw: Time is whatever you define it to be. I define it as a sequence of before-now-after. The fact that we can't observe the consequences of events before the BB (if it happened) does not mean there was no before, i.e. no cause, cause of the cause etc. You and I would agree on that, I think. Presumably, since he is an atheist, Hawking is convinced there is no point in considering any theory that cannot be verified by observation, because the universe consists only of its materials. That should be anathema to you, so I don't quite know why you're quoting him with such boldness. As for evidence, however, the Big Bang (if it happened) is no more evidence for a God than it is for chance, though no doubt you and Hawking would disagree - you one way and he the other.
DAVID: I am quoting him because the 'no boundaries' proposal specifically says there is no 'before' before the Big Bang. It specifically implies a creation of some sort. Naturally I choose God.
If there is no ‘before’, there is no God. If there is a ‘before’, it can just as easily have been mindless energy and matter as a conscious mind. I really don’t think for one moment that the atheist Hawking thinks his theory specifically implies a “creation” that would allow for your God.
Cosmology; Hawking's theory of a beginning
by David Turell , Monday, March 05, 2018, 14:57 (2456 days ago) @ dhw
DAVID’s comment: If time began at the Big Bang (that is the time of our reality) it looks like a creation to us. Of course, scientists can't bring in God as creator, but it is a piece of the evidence for God.
dhw: Time is whatever you define it to be. I define it as a sequence of before-now-after. The fact that we can't observe the consequences of events before the BB (if it happened) does not mean there was no before, i.e. no cause, cause of the cause etc. You and I would agree on that, I think. Presumably, since he is an atheist, Hawking is convinced there is no point in considering any theory that cannot be verified by observation, because the universe consists only of its materials. That should be anathema to you, so I don't quite know why you're quoting him with such boldness. As for evidence, however, the Big Bang (if it happened) is no more evidence for a God than it is for chance, though no doubt you and Hawking would disagree - you one way and he the other.
DAVID: I am quoting him because the 'no boundaries' proposal specifically says there is no 'before' before the Big Bang. It specifically implies a creation of some sort. Naturally I choose God.
dhw: If there is no ‘before’, there is no God. If there is a ‘before’, it can just as easily have been mindless energy and matter as a conscious mind. I really don’t think for one moment that the atheist Hawking thinks his theory specifically implies a “creation” that would allow for your God.
Of course he won't. And 'before' only God existed outside of time.
Cosmology; universe based on math & quantum mechanics
by David Turell , Monday, March 05, 2018, 16:33 (2456 days ago) @ David Turell
Recent research seems to show it:
https://phys.org/news/2018-03-massive-astrophysical-subatomic-equation.html
"Quantum mechanics is the branch of physics governing the sometimes-strange behavior of the tiny particles that make up our universe. Equations describing the quantum world are generally confined to the subatomic realm—the mathematics relevant at very small scales is not relevant at larger scales, and vice versa. However, a surprising new discovery from a Caltech researcher suggests that the Schrödinger Equation—the fundamental equation of quantum mechanics—is remarkably useful in describing the long-term evolution of certain astronomical structures.
***
"While teaching a Caltech course on planetary physics, Batygin (the theorist behind the proposed existence of Planet Nine) turned to an approximation scheme called perturbation theory to formulate a simple mathematical representation of disk evolution. This approximation, often used by astronomers, is based upon equations developed by the 18th-century mathematicians Joseph-Louis Lagrange and Pierre-Simon Laplace. Within the framework of these equations, the individual particles and pebbles on each particular orbital trajectory are mathematically smeared together. In this way, a disk can be modeled as a series of concentric wires that slowly exchange orbital angular momentum among one another.
***
"Using this approximation to model disk evolution, however, had unexpected results.
"When we do this with all the material in a disk, we can get more and more meticulous, representing the disk as an ever-larger number of ever-thinner wires," Batygin says. "Eventually, you can approximate the number of wires in the disk to be infinite, which allows you to mathematically blur them together into a continuum. When I did this, astonishingly, the Schrödinger Equation emerged in my calculations."
"The Schrödinger Equation is the foundation of quantum mechanics: It describes the non-intuitive behavior of systems at atomic and subatomic scales. One of these non-intuitive behaviors is that subatomic particles actually behave more like waves than like discrete particles—a phenomenon called wave-particle duality. Batygin's work suggests that large-scale warps in astrophysical disks behave similarly to particles, and the propagation of warps within the disk material can be described by the same mathematics used to describe the behavior of a single quantum particle if it were bouncing back and forth between the inner and outer edges of the disk.
"The Schrödinger Equation is well studied, and finding that such a quintessential equation is able to describe the long-term evolution of astrophysical disks should be useful for scientists who model such large-scale phenomena. Additionally, adds Batygin, it is intriguing that two seemingly unrelated branches of physics—those that represent the largest and the smallest of scales in nature—can be governed by similar mathematics.
"'This discovery is surprising because the Schrödinger Equation is an unlikely formula to arise when looking at distances on the order of light-years," says Batygin. "The equations that are relevant to subatomic physics are generally not relevant to massive, astronomical phenomena. Thus, I was fascinated to find a situation in which an equation tha
"'Fundamentally, the Schrödinger Equation governs the evolution of wave-like disturbances." says Batygin. "In a sense, the waves that represent the warps and lopsidedness of astrophysical disks are not too different from the waves on a vibrating string, which are themselves not too different from the motion of a quantum particle in a box. In retrospect, it seems like an obvious connection, but it's exciting to begin to uncover the mathematical backbone behind this reciprocity.'"
Comment: This is a giant hint that God uses math and quantum mechanics as the basis of the universe
Cosmology; universe based on math & quantum mechanics
by David Turell , Monday, February 17, 2020, 18:14 (1741 days ago) @ David Turell
Another article on the issue of a mathematical universe:
https://www.sciencenews.org/article/how-quantum-technique-highlights-math-mysterious-li...
"It has long been a mystery why pure math can reveal so much about the nature of the physical world.
"Antimatter was discovered in Paul Dirac’s equations before being detected in cosmic rays. Quarks appeared in symbols sketched out on a napkin by Murray Gell-Mann several years before they were confirmed experimentally. Einstein’s equations for gravity suggested the universe was expanding a decade before Edwin Hubble provided the proof. Einstein’s math also predicted gravitational waves a full century before behemoth apparatuses detected those waves (which were produced by collisions of black holes — also first inferred from Einstein’s math).
"Nobel laureate physicist Eugene Wigner alluded to math’s mysterious power as the “unreasonable effectiveness of mathematics in the natural sciences.” Somehow, Wigner said, math devised to explain known phenomena contains clues to phenomena not yet experienced — the math gives more out than was put in. “The enormous usefulness of mathematics in the natural sciences is something bordering on the mysterious and … there is no rational explanation for it,” Wigner wrote in 1960.
***
"In an enormously complicated 165-page paper, computer scientist Zhengfeng Ji and colleagues present a result that penetrates to the heart of deep questions about math, computing and their connection to reality. It’s about a procedure for verifying the solutions to very complex mathematical propositions, even some that are believed to be impossible to solve. In essence, the new finding boils down to demonstrating a vast gulf between infinite and almost infinite, with huge implications for certain high-profile math problems. Seeing into that gulf, it turns out, requires the mysterious power of quantum physics.
***
"Today’s quantum computers are relatively rudimentary, but in principle, an advanced model could crack codes by calculating the prime factors for enormously big numbers.
"That power stems, at least in part, from the weird phenomenon known as quantum entanglement. And it turns out that, similarly, quantum entanglement boosts the power of MIP provers. By sharing an infinite amount of quantum entanglement, MIP provers can verify vastly more complicated proofs than nonquantum MIP provers. [MIP refers to a mathematical theorum about proofs]
***
"...pursuit of this discovery quite possibly will turn up deeper implications for math, computer science and quantum physics.
"It probably won’t shed any light on controversies over the best way to interpret quantum mechanics, as computer science theorist Scott Aaronson notes in his blog about the new finding. But perhaps it could provide some sort of clues regarding the nature of infinity. That might be good for something, perhaps illuminating whether infinity plays a meaningful role in reality or is a mere mathematical idealization.
"On another level, the new work raises an interesting point about the relationship between math and the physical world. The existence of quantum entanglement, a (surprising) physical phenomenon, somehow allows mathematicians to solve problems that seem to be strictly mathematical. Wondering why physics helps out math might be just as entertaining as contemplating math’s unreasonable effectiveness in helping out physics. Maybe even one will someday explain the other."
Comment: Note this last paragraph. God, the master mathematician, has used math to create the universe. A reality based on quantum mechanics can let us use quantum mechanics to solve how God does it. One might note the almost thirty-year-old book, "Fearful Symmetry. Is God a Geometer?"
https://www.amazon.com/Fearful-Symmetry-Geometer-Dover-Mathematics/dp/0486477584
"This fascinating study explores a fundamental paradox behind the patterns of the natural world, in which symmetrical causes lead to asymmetrical effects. Lesser and greater patterns—the structure of subatomic particles, a tiger's stripes, the shapes of clouds, and the vibrations of the stars—are produced by broken symmetry. This accessible exploration of the physical and biological world employs the mathematical concepts of symmetry to consider the deepest questions of modern physics."
Cosmology; Hawking's theory of a beginning
DAVID: I am quoting him because the 'no boundaries' proposal specifically says there is no 'before' before the Big Bang. It specifically implies a creation of some sort. Naturally I choose God.
dhw: If there is no ‘before’, there is no God. If there is a ‘before’, it can just as easily have been mindless energy and matter as a conscious mind. I really don’t think for one moment that the atheist Hawking thinks his theory specifically implies a “creation” that would allow for your God.
DAVID: Of course he won't. And 'before' only God existed outside of time.
“Time” is irrelevant if you accept my definition of time as a sequence of before-now-after. Either there was or there was not a “before” the Big Bang. Hawking says there wasn’t, and you say there was. If there was a before, that does not prove that the before must have been a God. It could have been eternal energy and matter.
Cosmology; Hawking's theory of a beginning
by David Turell , Tuesday, March 06, 2018, 18:24 (2454 days ago) @ dhw
DAVID: I am quoting him because the 'no boundaries' proposal specifically says there is no 'before' before the Big Bang. It specifically implies a creation of some sort. Naturally I choose God.
dhw: If there is no ‘before’, there is no God. If there is a ‘before’, it can just as easily have been mindless energy and matter as a conscious mind. I really don’t think for one moment that the atheist Hawking thinks his theory specifically implies a “creation” that would allow for your God.
DAVID: Of course he won't. And 'before' only God existed outside of time.
dhw" “Time” is irrelevant if you accept my definition of time as a sequence of before-now-after. Either there was or there was not a “before” the Big Bang. Hawking says there wasn’t, and you say there was. If there was a before, that does not prove that the before must have been a God. It could have been eternal energy and matter.
Pure eternal energy has no particles. We see it in the lab as plasma, not real matter as we know it. What has appeared from that initial state includes time and organized matter, requiring a designer, who was/is the eternal One.
Cosmology; importance of a beginning
by David Turell , Tuesday, May 07, 2019, 00:25 (2028 days ago) @ David Turell
Cosmology has problems related to theories of a beginning:
https://principia-scientific.org/cosmology-has-some-big-problems/
Born out of a cosmic explosion 13.8 billion years ago, the universe rapidly inflated and then cooled, it is still expanding at an increasing rate and mostly made up of unknown dark matter and dark energy … right?
This well-known story is usually taken as a self-evident scientific fact, despite the relative lack of empirical evidence—and despite a steady crop of discrepancies arising with observations of the distant universe.
In recent months, new measurements of the Hubble constant, the rate of universal expansion, suggested major differences between two independent methods of calculation. Discrepancies on the expansion rate have huge implications not simply for calculation but for the validity of cosmology’s current standard model at the extreme scales of the cosmos.
Another recent probe found galaxies inconsistent with the theory of dark matter, which posits this hypothetical substance to be everywhere. But according to the latest measurements, it is not, suggesting the theory needs to be reexamined.
***
For a crucial function of theories such as dark matter, dark energy and inflation, which each in its own way is tied to the big bang paradigm, is not to describe known empirical phenomena but rather to maintain the mathematical coherence of the framework itself while accounting for discrepant observations. Fundamentally, they are names for something that must exist insofar as the framework is assumed to be universally valid.
***
Consider the context of the problem and its history. As a mathematically driven science, cosmological physics is usually thought to be extremely precise. But the cosmos is unlike any scientific subject matter on earth. A theory of the entire universe, based on our own tiny neighborhood as the only known sample of it, requires a lot of simplifying assumptions. When these assumptions are multiplied and stretched across vast distances, the potential for error increases, and this is further compounded by our very limited means of testing.
***
The crux of today’s cosmological paradigm is that in order to maintain a mathematically unified theory valid for the entire universe, we must accept that 95 percent of our cosmos is furnished by completely unknown elements and forces for which we have no empirical evidence whatsoever. For a scientist to be confident of this picture requires an exceptional faith in the power of mathematical unification.
In the end, the conundrum for cosmology is its reliance on the framework as a necessary presupposition for conducting research. For lack of a clear alternative, as astrophysicist Disney also notes, it is in a sense stuck with the paradigm. It seems more pragmatic to add new theoretical floors than to rethink the fundamentals.
Contrary to the scientific ideal of getting progressively closer to the truth, it looks rather like cosmology, to borrow a term from technology studies, has become path-dependent: overdetermined by the implications of its past inventions.
Comment: Not a very solid edifice. Please read on in the next entry for a different set of thoughts.
Cosmology; importance of a beginning
by David Turell , Tuesday, May 07, 2019, 00:45 (2028 days ago) @ David Turell
Another point of view. Rob Sheldon's take: Reconsider the 'beginning' and answer Ekeberg:
https://uncommondescent.com/intelligent-design/rob-sheldon-the-real-reason-there-is-a-c...
"The edifice of the Big Bang has some serious cracks in it. It isn’t that physics models have to be perfect, but this one is so essential to the entire field, there’s a feeling of the ground shifting under the cosmologists feet. You might even say that cosmology wasn’t a field of physics until this model came along.
"Bit by dribbled bit, the data from Planck has been analyzed so thoroughly and squeezed so hard they’ve gotten blood from this turnip. That’s what the 6-digit accuracy on the Big Bang model is all about, which the Europeans proudly call “precision cosmology.”
***
"Let me say what Bjorn [Ekeberg]can’t–the discrepancies are a consequence of bad metaphysics (like the reason Einstein added the cosmological constant to the model) and are irreparable.
"Either the universe has a beginning, or it doesn’t, and if it has a beginning we are not going to escape it with bouncing or multiverses or inflation or wormholes. We must accept the metaphysical consequences of a beginning and move on. Nearly everything that has failed about the Big Bang model has been added because of bad metaphysics, a refusal to accept the consequences of a beginning.
"The remaining pieces of the Big Bang model that are failing and which can’t be attributed to bad metaphysics were added from sheer laziness (or to say it more generously) from the limitations of paper-and-pencil calculations and primitive computers. We now have both better mathematical tools and better computers, so neither of these excuses work any longer. Therefore there is no reason to assume isotropic, homogeneous, non-magnetic solutions are the only valid ones.
***
"And this is where I part ways with Ekeberg. He has only suggested that the model is wrong, he has not suggested how it can be repaired. He hints at some of the options: Do we add “new physics”, “new particles”, or abandon “old physics”
***
"My solution is none of those things. Rather, I argue we need to abandon all the bad metaphysics that motivated the add-ons to the model. That would be inflation, isotropy, homogeneity, dark energy, “dark matter” in its “new particle” expression, and of course, non-magnetic “gas”. Once all these barnacles are off the model, we can then embrace the difficulties of a fully kinetic plasma (ie. not MHD), a fully 3-D model, and cast about for formulations that can effectively explain the data.
"What gets me excited, is that my preliminary research shows that we have some excellent candidate models with nothing more exotic than extremely large magnetic fields. Some would hold that any magnetic field at all is exotic, but I reply that at least we have lots of evidence of astrophysical objects with large magnetic fields, making this assumption far more empirical than “new particles” or “MOND”. In other words, all we need is courage and bravery, willing to face the criticism and the difficulties of non-homogeneous, anisotropic, 3-D models.
"What we don’t need, however, is some sort of metaphysical justification for abandoning empirical physics or believing in 5 dimensions and invisible particles. It isn’t our faith in the philosophy of science that needs repair, but our former gullibility that let scientists slip in bad metaphysics.
"The hard work of the Planck team is not wasted, because the repairs to the model will make it even more physical, and therefore not just “precise” but also “accurate”. The ground may be shifting in cosmology, but it is finding its true foundation."
Comment: I should note that Rob Sheldon accepts that God exists. He is a research cosmologist and has worked on the Planck findings. My view is take a neutral view of science, neither pro-God or anti-God and study the results. Underlying bias has no place in scientific thinking about cosmology or evolution as we have discussed.
Cosmology; importance of a beginning
QUOTES from Ekeberg: Born out of a cosmic explosion 13.8 billion years ago, the universe rapidly inflated and then cooled, it is still expanding at an increasing rate and mostly made up of unknown dark matter and dark energy … right?
This well-known story is usually taken as a self-evident scientific fact, despite the relative lack of empirical evidence—and despite a steady crop of discrepancies arising with observations of the distant universe.
“…”the cosmos is unlike any scientific subject matter on earth. A theory of the entire universe, based on our own tiny neighborhood as the only known sample of it, requires a lot of simplifying assumptions. When these assumptions are multiplied and stretched across vast distances, the potential for error increases, and this is further compounded by our very limited means of testing.
QUOTE from Sheldon: "The edifice of the Big Bang has some serious cracks in it. It isn’t that physics models have to be perfect, but this one is so essential to the entire field, there’s a feeling of the ground shifting under the cosmologists feet."
DAVID: I should note that Rob Sheldon accepts that God exists. He is a research cosmologist and has worked on the Planck findings. My view is take a neutral view of science, neither pro-God or anti-God and study the results. Underlying bias has no place in scientific thinking about cosmology or evolution as we have discussed.
Thank you for these very important articles. It is clear that both authors are sceptical about the Big Bang theory and all the theories derived from it. Of course that doesn’t mean it is wrong, but it is certainly not to be regarded as scientific fact, despite the many text books which present it as such. For what it’s worth, I have always been sceptical of the very concept of a beginning out of nothing. Until today, you have argued that only your eternal God, who is pure energy, could have preceded the Big Bang. I have proposed that whether there was a Big Bang or not, the universe has always existed in the form of energy and matter constantly changing itself. Once again, thank you for drawing our attention to this welcome challenge to current scientific dogma.
Cosmology; importance of a beginning
by David Turell , Tuesday, May 07, 2019, 14:57 (2028 days ago) @ dhw
QUOTES from Ekeberg: Born out of a cosmic explosion 13.8 billion years ago, the universe rapidly inflated and then cooled, it is still expanding at an increasing rate and mostly made up of unknown dark matter and dark energy … right?
This well-known story is usually taken as a self-evident scientific fact, despite the relative lack of empirical evidence—and despite a steady crop of discrepancies arising with observations of the distant universe.“…”the cosmos is unlike any scientific subject matter on earth. A theory of the entire universe, based on our own tiny neighborhood as the only known sample of it, requires a lot of simplifying assumptions. When these assumptions are multiplied and stretched across vast distances, the potential for error increases, and this is further compounded by our very limited means of testing.
QUOTE from Sheldon: "The edifice of the Big Bang has some serious cracks in it. It isn’t that physics models have to be perfect, but this one is so essential to the entire field, there’s a feeling of the ground shifting under the cosmologists feet."
DAVID: I should note that Rob Sheldon accepts that God exists. He is a research cosmologist and has worked on the Planck findings. My view is take a neutral view of science, neither pro-God or anti-God and study the results. Underlying bias has no place in scientific thinking about cosmology or evolution as we have discussed.
dhw: Thank you for these very important articles. It is clear that both authors are sceptical about the Big Bang theory and all the theories derived from it. Of course that doesn’t mean it is wrong, but it is certainly not to be regarded as scientific fact, despite the many text books which present it as such. For what it’s worth, I have always been sceptical of the very concept of a beginning out of nothing. Until today, you have argued that only your eternal God, who is pure energy, could have preceded the Big Bang. I have proposed that whether there was a Big Bang or not, the universe has always existed in the form of energy and matter constantly changing itself. Once again, thank you for drawing our attention to this welcome challenge to current scientific dogma.
Thank you. The expanding universe gives rise to the theory , which tries to answer the question, expanding from what? Einstein's theories lead to singularity, but what is missing is quantum gravity, which doesn't want to fit into the studies.
Cosmology; fine tuning factor confirmed
by David Turell , Monday, February 24, 2020, 19:08 (1734 days ago) @ David Turell
The fine structure constant is confirmed as unchanged by a black hole:
https://www.sciencenews.org/article/fine-structure-constant-remains-same-even-near-blac...
"According to standard physics, the fine-structure constant, which governs interactions of electrically charged particles, is the same everywhere in the universe. Some alternative theories, however, suggest that the constant might be different in certain locales, such as the extreme gravitational environment around a black hole. But when put to the test near the supermassive black hole at the center of the Milky Way, the number didn’t budge, physicists report in a paper accepted in Physical Review Letters.
"The fine-structure constant is one of an assortment of unchanging numbers found in physics formulas, such as the mass of an electron or the speed of light. It determines the strength with which electrically charged particles pull on one another. Scientists don’t know why it has the value it does — about 1/137. But its size seems crucial: If that number were much different, atoms wouldn’t form.
***
"It’s the first time scientists have searched for a variation of the fine-structure constant in the general vicinity of a black hole, says Wim Ubachs of Vrije Universiteit Amsterdam, a physicist who previously has searched for changes in various constants of nature.
"A 2010 study gave tentative hints that the fine-structure constant might vary as scientists look farther out into space, with the number increasing or decreasing in certain directions, but the evidence for that phenomenon is not conclusive (SN: 9/3/10). So scientists are probing the constant in a variety of ways, including near a black hole.
“'The work is very important because it denotes the beginning of a new type of study,” namely, searching for variation of the fine-structure constant at the center of the galaxy, says physicist John Webb of the University of New South Wales in Sydney.
"In previous research, Webb and colleagues found no variation while probing the fine-structure constant in an environment that’s even more gravitationally extreme: the surface of dense dead stars called white dwarfs. So if the new research had found any indication of change in the steadfast constant, Webb says, “I would have been very surprised.'”
Comment: All the fine tuning values are well-known, but surprisingly the reasons for each exact number is not understood. God works are still mysterious in many ways.
Cosmology; new studies of universe's magnetic fields
by David Turell , Thursday, July 02, 2020, 19:53 (1605 days ago) @ David Turell
No new advanced theories of the origin of the magnetic fields in the universe, but increased study is occurring:
https://www.quantamagazine.org/the-hidden-magnetic-universe-begins-to-come-into-view-20...
"Twenty years ago, astronomers started to detect magnetism permeating entire galaxy clusters, including the space between one galaxy and the next. Invisible field lines swoop through intergalactic space like the grooves of a fingerprint.
"Last year, astronomers finally managed to examine a far sparser region of space — the expanse between galaxy clusters. There, they discovered the largest magnetic field yet: 10 million light-years of magnetized space spanning the entire length of this “filament” of the cosmic web. A second magnetized filament has already been spotted elsewhere in the cosmos by means of the same techniques. “We are just looking at the tip of the iceberg, probably,” said Federica Govoni of the National Institute for Astrophysics in Cagliari, Italy, who led the first detection.
"The question is: Where did these enormous magnetic fields come from?
***
"One possibility is that cosmic magnetism is primordial, tracing all the way back to the birth of the universe. In that case, weak magnetism should exist everywhere, even in the “voids” of the cosmic web — the very darkest, emptiest regions of the universe. The omnipresent magnetism would have seeded the stronger fields that blossomed in galaxies and clusters.
***
"The problem at the heart of the Hubble tension is that the universe seems to be expanding significantly faster than expected based on its known ingredients. In a paper posted online in April and under review with Physical Review Letters, the cosmologists Karsten Jedamzik and Levon Pogosian argue that weak magnetic fields in the early universe would lead to the faster cosmic expansion rate seen today.
"Primordial magnetism relieves the Hubble tension so simply that Jedamzik and Pogosian’s paper has drawn swift attention. “This is an excellent paper and idea,” said Marc Kamionkowski, a theoretical cosmologist at Johns Hopkins University who has proposed other solutions to the Hubble tension.
***
"If these magnetic fields arose in the infant universe, the question becomes: How?"
***
“'I thought, wow,” Pogosian said, “this could be pointing us to [magnetic fields’] actual presence. So I wrote Karsten immediately.” The two got together in Montpellier in February, just before the lockdown. Their calculations indicated that, indeed, the amount of primordial magnetism needed to address the Hubble tension also agrees with the blazar observations and the estimated size of initial fields needed to grow the enormous magnetic fields spanning galaxy clusters and filaments. “So it all sort of comes together,” Pogosian said, “if this turns out to be right.'”
Comment: The content of this article describes much of the recent studies and theoretical ideas. It is a work in progress
Cosmology; magnetic fields may pay a role in planets birth
by David Turell , Friday, July 23, 2021, 00:00 (1220 days ago) @ David Turell
A new study offers support:
http://abstractions.nautil.us/article/702/astronomers-find-secret-planet-making-ingredi...
"For some time now, scientists have suspected that magnetism may also play a role. What, specifically, magnetic fields do has remained unclear, partly because of the difficulty in including magnetic fields alongside gravity in the computer models used to investigate planet formation. In astronomy, said Meredith MacGregor, an astronomer at the University of Colorado, Boulder, there’s a common refrain: “We don’t bring up magnetic fields, because they’re difficult.”
"And yet magnetic fields are commonplace around planetesimals and protoplanets, coming either from the star itself or from the movement of starlight-washed gas and dust. In general terms, astronomers know that magnetic fields may be able to protect nascent planets from a star’s wind, or perhaps stir up the disk and move planet-making material about. “We’ve known for a long time that magnetic fields can be used as a shield and be used to disrupt things,” said Zoë Leinhardt, a planetary scientist at the University of Bristol who was not involved with the work. But details have been lacking, and the physics of magnetic fields at this scale are poorly understood.
“'It’s hard enough to model the gravity of these disks in high enough resolution and to understand what’s going on,” said Ravit Helled, a planetary scientist at the University of Zurich. Adding magnetic fields is a significantly larger challenge.
"In the new work, Helled, used the fastest [computer] in Europe, to run extremely high-resolution simulations that incorporated magnetic fields alongside gravity.
"Magnetism seems to have three key effects. First, magnetic fields shield certain clumps of gas—those that may grow up to be smaller planets—from the destructive influence of stellar radiation. In addition, those magnetic cocoons also slow down the growth of what would have become supermassive planets. The magnetic pressure pushing out into space “stops the infalling of new matter,” said Mayer, “maybe not completely, but it reduces it a lot.”
"The third apparent effect is both destructive and creative. Magnetic fields can stir gas up. In some cases, this influence disintegrates protoplanetary clumps. In others, it pushes gas closer together, which encourages clumping.
***
"At this stage, we can’t be totally sure what is happening with magnetic fields on a protoplanetary scale. “This is more a proof of concept, that they can do this, they can marry the gravity and the magnetic fields to do something very interesting that I haven’t seen before.'”
Comment: the activities in the universe are so complex, we still have much to discover.
Cosmology; knowing a star's age is difficult
by David Turell , Saturday, July 24, 2021, 19:17 (1218 days ago) @ David Turell
There are several methods, with uncertain accuracy:
https://www.sciencenews.org/article/star-age-calculation-astronomy-life-cycle
"But the one variable scientists haven’t quite cracked yet is time.
“The sun is the only star we know the age of,” says astronomer David Soderblom of the Space Telescope Science Institute in Baltimore. “Everything else is bootstrapped up from there.”
***
"Scientists do have a pretty good handle on how stars are born, how they live and how they die. For instance, stars burn through their hydrogen fuel, puff up and eventually expel their gases into space, whether with a bang or a whimper. But when exactly each stage of a star’s life cycle happens is where things get complicated. Depending on their mass, certain stars hit those points after a different number of years. More massive stars die young, while less massive stars can burn for billions of years.
"At the turn of the 20th century, two astronomers — Ejnar Hertzsprung and Henry Norris Russell — independently came up with the idea to plot stars’ temperature against their brightness. The patterns on these Hertzsprung-Russell, or H-R, diagrams corresponded to where different stars were in that life cycle. Today, scientists use these patterns to determine the age of star clusters, whose stars are thought to have all formed at the same time.
"The caveat is that, unless you do a lot of math and modeling, this method can be used only for stars in clusters, or by comparing a single star’s color and brightness with theoretical H-R diagrams. “It’s not very precise,” says astronomer Travis Metcalfe of the Space Science Institute in Boulder, Colo. “Nevertheless, it’s the best thing we’ve got.”
"By the 1970s, astrophysicists had noticed a trend: Stars in younger clusters spin faster than stars in older clusters. In 1972, astronomer Andrew Skumanich used a star’s rotation rate and surface activity to propose a simple equation to estimate a star’s age: Rotation rate = (Age) -½.
"This was the go-to method for individual stars for decades, but new data have poked holes in its utility. It turns out that some stars don’t slow down when they hit a certain age. Instead they keep the same rotation speed for the rest of their lives.
“'Rotation is the best thing to use for stars younger than the sun,” Metcalfe says. For stars older than the sun, other methods are better.
***
"Watching a star flicker can give clues to its age. Scientists look at changes in a star’s brightness as an indicator of what’s happening beneath the surface and, through modeling, roughly calculate the star’s age. To do this, one needs a really big dataset on the star’s brightness — which the Kepler telescope could provide.
“'Everybody thinks it was all about finding planets, which was true,” Soderblom says. “But I like to say that the Kepler mission was a stealth stellar physics mission.'”
Comment: This only shows we still don't know much about our universe, but we do know it is fine-tuned-for-life