Posted on 09/09/2001 1:05:44 PM PDT by telos
A GROUP of astronomers and cosmologists has warned that the laws thought to govern the universe, including Albert Einstein's theory of relativity, must be rewritten. The group, which includes Professor Stephen Hawking and Sir Martin Rees, the astronomer royal, say such laws may only work for our universe but not in others that are now also thought to exist. "It is becoming increasingly likely that the rules we had thought were fundamental through time and space are actually just bylaws for our bit of it," said Rees, whose new book, Our Cosmic Habitat, is published next month. "Creation is emerging as even stranger than we thought." Among the ideas facing revision is Einstein's belief that the speed of light must always be the same - 186,000 miles a second in a vacuum. There is growing evidence that light moved much faster during the early stages of our universe. Rees, Hawking and others are so concerned at the impact of such ideas that they recently organised a private conference in Cambridge for more than 30 leading cosmologists. Cosmology - the study of the origins and future of our universe - became popular in the early 20th century for physicists who wanted to think the unthinkable about creation. Einstein's theory of relativity, which describes how gravity controls the behaviour of our universe, was one of cosmology's greatest triumphs. But Einstein said there was an even deeper issue, which he described as whether God had any choice. In other words, could the laws that governed the way our universe formed after the big bang have worked any differently? He concluded that they could not. In the past 40 years, however, the increasing power of astronomical instruments has turned cosmology from a theoretical science into a practical one and forced scientists to re-examine Einstein's conclusions. Among the most striking claims is that our universe only exists because of a fine balance between several crucial factors. One is the rate at which nuclear fusion releases energy in stars such as the sun by squashing hydrogen atoms into helium and then other elements. Astronomers have found that exactly 0.7% of the mass of the hydrogen is converted into starlight and that if this figure had been just a fraction different then carbon and other elements essential to life could never have formed. Another puzzle is the so-called "smoothness" of our universe, by which astronomers mean the distribution of matter and radiation. In theory, the big bang could have produced a universe where all the matter clumped together into a few black holes, or another in which it was spread out evenly, forming nothing but a thin vapour. "It could be that the laws that govern our universe are unchangeable but it is a remarkable coincidence that these laws are also exactly what is needed to produce life," said Rees. "It seems too good to be true." What he, Hawking and others such as Neil Turok, professor of maths and physics at Cambridge, are now looking at is the idea that our universe is just one of an infinite number of universes, with different laws of nature operating in each. Some universes would have all their matter clumped together into a few huge black holes while others would be nothing more than a thin uniform freezing gas. However, Hawking and his colleagues increasingly disagree over how this "multiverse" could work. At the conference Hawking dismissed the idea of a series of big bangs on the grounds that it extended into the infinite past and so could never have a beginning.
At which point we will tranq him, tag his ear and release him back into the wild
to monitor his migration and mating habits.
(This place is an info gold mine!)
At the conference Hawking dismissed the idea of a series of big bangs on the grounds that it extended into the infinite past and so could never have a beginning.PH, I know that this isn't what you wanted to hear.
They have no evidence. I'm still in the game.
Among the ideas facing revision is Einstein's belief that the speed of light must always be the same - 186,000 miles a second in a vacuum. There is growing evidence that light moved much faster during the early stages of our universe.This doesn't bother me. In the very early universe, light could have moved faster. That's virtually implied by cosmological inflation. As long as no causality violations are involved, I see no problems. Now, of course, there are definite problems if we start traveling or communicating faster than light. But initially, photons moving out to the horizon faster than c, that's no big deal, theoretically. Or am I missing something?
I believe it does pose a problem, in that our method of "divining" the properties of the Big Bang is by projecting backwards in time the currently expanding Universe and applying the Theory General Relativity to see what the conditions must have been in earlier stages of the Universe's evolution. It seems to me that one cannot hold the belief that General Relativity is valid all the way back to the BB AND concurrently believe that at some earlier time in the history of the Universe light traveled at a speed >c, as the constancy of the speed of light is an assumption which underlies Special Relativity, which is nothing more than General Relativity in the absence gravity.
In other words, it seems to me that this would constitute asserting that Relativity was both true and NOT true at some point in the history of the Universe. This seems untenable, but perhaps there's more to the story that I don't understand.
I was making a one-time only exception during the brief period of cosmological inflation. I'm still reading Guth, so I'm fuzzy on this, but I thought that ftl expansion of everything is implied at that time.
You have me at a disadvantage, in that I have NOT read Guth at all. Notwithstanding that, I think I see the problem.
The "inflation" does proceed FTL. It is an inflation of space itself, and thus no matter (AFAIK) is being shunted around at FTL speeds, and no information is transferred FTL; hence, no violation of the Theory of Relativity.
If Guth says otherwise, I'll defer to his wisdom on the subject, but that's what I think is going on. Neither light (nor matter) is travelling FTL during the inflation, but the fabric of space does..... no violation; no harm.
I similarly defer to "Physicist" if he has a correction to my remarks.
I trust "temporally infinite" was a typo. Surely you meant "temporarily infinite."
</silly mode> (Don't shoot!)
I too defer to Physicist. But I think that the inflationary expansion of space -- you're correct in that -- does involve moving those photons, which are in space. Perhaps this is a minor quibble to prevent Enstein from spinning in his grave. And as I tried to say before, this doesn't involve transferring information FTL, because it's strictly one-way, and no one is "out there" to receive this information. Thus no causality violations. If causality is preserved, I can sleep easy.
Got something better to do with your time? Like count Bonds HRs? Or is that measuring the universe as well?
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