Far out cosmology: Multiverse essay (Introduction)

by David Turell , Monday, March 21, 2016, 14:18 (3168 days ago) @ David Turell

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.