Posted on 09/09/2001 1:05:44 PM PDT by telos
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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