Posted on 07/14/2009 6:09:21 PM PDT by SeekAndFind
BRIAN GREENE spent a good part of the last decade extolling the virtues of string theory. He dreamed that one day it would provide physicists with a theory of everything that would describe our universe - ours and ours alone. His bestselling book The Elegant Universe eloquently captured the quest for this ultimate theory.
"But the fly in the ointment was that string theory allowed for, in principle, many universes," says Greene, who is a theoretical physicist at Columbia University in New York. In other words, string theory seems equally capable of describing universes very different from ours. Greene hoped that something in the theory would eventually rule out most of the possibilities and single out one of these universes as the real one: ours.
So far, it hasn't - though not for any lack of trying. As a result, string theorists are beginning to accept that their ambitions for the theory may have been misguided. Perhaps our universe is not the only one after all. Maybe string theory has been right all along.
Greene, certainly, has had a change of heart. "You walk along a number of pathways in physics far enough and you bang into the possibility that we are one universe of many," he says. "So what do you do? You smack yourself in the head and say, 'Ah, maybe the universe is trying to tell me something.' I have personally undergone a sort of transformation, where I am very warm to this possibility of there being many universes, and that we are in the one where we can survive.
(Excerpt) Read more at newscientist.com ...
Greene’s transformation is emblematic of a profound change among the majority of physicists. Until recently, many were reluctant to accept this idea of the “multiverse”, or were even belligerent towards it. However, recent progress in both cosmology and string theory is bringing about a major shift in thinking. Gone is the grudging acceptance or outright loathing of the multiverse. Instead, physicists are starting to look at ways of working with it, and maybe even trying to prove its existence.
If such ventures succeed, our universe will go the way of Earth - from seeming to be the centre of everything to being exposed as just a backwater in a far vaster cosmos. And just as we are unable to deduce certain aspects of Earth from first principles - such as its radius or distance from the sun - we will have to accept that some things about our universe are a random accident, inexplicable except in the context of the multiverse.
However, if our universe is part of a multiverse then we can ascribe the value of the cosmological constant to an accident. The same goes for other aspects of our universe, such as the mass of the electron. The idea is simply that each universe’s laws of physics and fundamental constants are randomly determined, and we just happen to live in one where these are suited for life. “If not for the multiverse, you would have these unsolved problems at every corner,” says Linde.
Hmm seems like they just made it up to make their equations make sense.
It's just a hunch but it seems remarkably elegant to me.
You know, some freeper is going to read this and post something silly:
“String theory requires that the universe has a property known as supersymmetry, which posits that every particle known to physicists has a heavier and as yet unseen superpartner.”
I have that book, Parallel Worlds,or whatever by that guy Macchu Pichu, and it is difficult, to say the least.
parsy, who tries to keep up but geeeesh
What do you mean a hunch-- isn't that pretty much what they're saying? I mean that was an episode of Star Trek over 10 years ago. In fact, here's a LINK.
Justice League comics were pushing this almost 50 years ago. It allowed DC to retool popular superheroes (eg Flash) and bring back the old versions from “the other Earth” every once in a while.
Woit’s book “Not Even Wrong” was a terrific exploration of the subject. Essentially he explained that maybe physicists shouldn’t be putting all their eggs in a basket that no one’s come close to offering any evidence for. Maybe a few people should stick with string theory and everyone else should skip the unproven meme and look to other ideas that might actually be provable sometime in the near future.
bump
bump
Maybe they're random; maybe they're not; that has not yet been determined, nor, considering the vast differences involved, can it.
I’m really not qualified to comment since I only made it through University and have yet to complete my Multiversity level studies but the idea that there are multiple Universes is intriguing.
You may be more right than you know.
I've Read Brian Greene's "The Fabric of the Cosmos" and it is clear that he is both a very good writer and a very good physicist. 'Cosmos' was a well written and a very entertaining and informative book. In particular, his explanation of Bell's Theorem (weird action at a distance) is far superior to any other description that I have seen - it's actually understandable.
But when Greene get's to String Theory his arguments get very weak. Here is a theory that has been under development for over three decades, promises to explain anything and everything but has yet to be subjected to even a single simple experiment that would validate the basic assumptions, predictions and principles of the theory. So I say: What good is such a theory? In my very, very humble opinion, it's not worth much. I expect that in the end String Theory will to fail to produce because that has been it's track record for a good share of my life. Enough I say. Let some of our bright young physicists work on something else.
Here's the entrance to the multiverse for the 'Sliders' crew.
“If not for the multiverse, you would have these unsolved problems at every corner,” says Linde.
Baaah! If you didn’t have multiverse you wouldn’t HAVE
corners.
Best metaphor I ever encountered:
An old (1960’s) Astro Boy cartoon where he explained it as the other side of a piece of paper.
B4l8r
I mean I have no evidence but the idea is elegant. It’s compelling.
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