
#73
Jan2412, 11:05 AM

Astronomy
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The question Edge asked in 2005 was "WHAT DO YOU BELIEVE IS TRUE EVEN THOUGH YOU CANNOT PROVE IT?" ==quote Edge 2005 annual question== Paul Steinhardt Albert Einstein Professor of Physics, Princeton University. I believe that our universe is not accidental, but I cannot prove it. Historically, most physicists have shared this pointofview. For centuries, most of us have believed that the universe is governed by a simple set of physical laws that are the same everywhere and that these laws derive from a simple unified theory. However, in the last few years, an increasing number of my most respected colleagues have become enamored with the anthropic principle—the idea that there is an enormous multiplicity of universes with widely different physical properties and the properties of our particular observable universe arise from pure accident. The only special feature of our universe is that its properties are compatible with the evolution of intelligent life. The change in attitude is motivated, in part, by the failure to date to find a unified theory that predicts our universe as the unique possibility. According to some recent calculations, the current best hope for a unified theory—superstring theory—allows an exponentially large number of different universes, most of which look nothing like our own. String theorists have turned to the anthropic principle for salvation. Frankly, I view this as an act of desperation. I don't have much patience for the anthropic principle. I think the concept is, at heart, nonscientific. A proper scientific theory is based on testable assumptions and is judged by its predictive power. The anthropic principle makes an enormous number of assumptions—regarding the existence of multiple universes, a random creation process, probability distributions that determine the likelihood of different features, etc.—none of which are testable because they entail hypothetical regions of spacetime that are forever beyond the reach of observation. As for predictions, there are very few, if any. In the case of string theory, the principle is invoked only to explain known observations, not to predict new ones. (In other versions of the anthropic principle where predictions are made, the predictions have proven to be wrong. Some physicists cite the recent evidence for a cosmological constant as having anticipated by anthropic argument; however, the observed value does not agree with the anthropically predicted value.) I find the desperation especially unwarranted since I see no evidence that our universe arose by a random process. Quite the contrary, recent observations and experiments suggest that our universe is extremely simple. The distribution of matter and energy is remarkably uniform. The hierarchy of complex structures ranging from galaxy clusters to subnuclear particles can all be described in terms of a few dozen elementary constituents and less than a handful of forces, all related by simple symmetries. A simple universe demands a simple explanation. Why do we need to postulate an infinite number of universes with all sorts of different properties just to explain our one? Of course, my colleagues and I are anxious for further reductionism. But I view the current failure of string theory to find a unique universe simply as a sign that our understanding of string theory is still immature (or perhaps that string theory is wrong). Decades from now, I hope that physicists will be pursuing once again their dreams of a truly scientific "final theory" and will look back at the current anthropic craze as millennial madness. ==endquote== http://edge.org/responsedetail/805/...annotproveit 



#74
Jan2412, 12:43 PM

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#75
Jan2412, 01:35 PM

P: 75

http://www.youtube.com/watch?v=VOz4P...eature=related Videos like these and many more show animations of the big bang, they show it as an observer somewhere outside of the universe. They put these on all the science channels as well, why would they put false information like this in the public and give them faulty ideas of the big bang if it is not true. From what you stated this animation cannot be valid because there is no edge or outside of the universe, correct? 



#76
Jan2412, 01:51 PM

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#77
Jan2412, 02:02 PM

P: 75





#78
Jan2412, 02:05 PM

P: 15,325

The visualization is in the math. Anything that is not described via math is necessarily flawed (that's the nature of models and metaphors). 



#79
Jan2412, 02:08 PM

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#80
Jan2412, 02:10 PM

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#81
Jan2412, 02:19 PM

P: 75

The point I was trying to get to is, if there indeed is more universes out there. A multiverse would be in effect, and the following is true.
The universe has and edge. The universe is expanding into a larger space. Our universe is not infinite. Therefor there is a center to our universe. Weather math can show us where or not. 



#82
Jan2412, 02:22 PM

P: 226

Probably the best counter to Steinhardt's arguement is that alot of effort and science has gone into argung our position in the universe is not special, so why should it follow that the universe as a whole is special.
I agree, however, that pushing multiverses when you can't prove it shouldn't be soaking up sciencetime. An above poster said there was no value in discussing vantage points from outside the universe. That's a prediction about the future. Until the conversation has taken place, we have no idea what value it might have. Every avenue should be explored. 



#83
Jan2412, 02:30 PM

P: 226

I was going to call our universe Cronos, but decided it was too lofty for the subject matter, so Mark it was. If it really helps you, let's go back to the ballon analogy. The center of the ballon, the universe, is Zero Time, the interior is the past, the exterior the future. That's the closest you're going to get to having a center. 



#84
Jan2412, 02:34 PM

P: 75





#85
Jan2412, 02:42 PM

P: 226

The Earth's surface has no center. Where ever you stand upon it there is an equal amount of mileage in any direction before you arrive back where you started. The finite, unbound universe is treated the same way. Where ever you position yourself, here, Andromeda, the Sloan Wall, you will always have an equal amount of lightyears in every direction before you arrive back at where you started.
Have you ever played the old computer game Asteroid? If you are familiar with the idea of the ships and asteroids disappearing off the edge of the screen and reappearing at the opposite edge, then you have the idea of a finite, unbound universe. To further visualise it, imagine that the ship remained in the middle at all times and travelling around simply scrolled the screen around (like a platformer game does). In any case, all you can ever have is a starting point. But there are no starting points of any special property that they can be called the center. 



#86
Jan2412, 02:51 PM

P: 38

Science should never be dogmatic. 



#87
Jan2412, 02:55 PM

P: 75





#88
Jan2412, 03:28 PM

P: 38





#89
Jan2412, 03:39 PM

P: 15,325

Likewise, you can walk along a surface and find yourself back where you started without the surface having to enclose anything, thus without it having to have a centre at all. 



#90
Jan2412, 05:22 PM

P: 226




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