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Post by Progenitor A on Mar 3, 2011 10:50:32 GMT 1
A question asked today by:
Carlos Frenk
Director of the Institute for Computational Cosmology at the University of Durham
On Melvyn Bragg's R4 'How Old Is The Universe?'
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Post by abacus9900 on Mar 3, 2011 11:19:57 GMT 1
A question asked today by: Carlos Frenk Director of the Institute for Computational Cosmology at the University of Durham On Melvyn Bragg's R4 'How Old Is The Universe?' Oh dear, nay, you're gonna get STA all worked up now! She, in common with many other physicists and or cosmologists seems to think that all of creation began with the BB. Not very likely though is it? There was an 'Horizon' programme screened sometime last year where most of the 'experts' appearing on it did not any longer consider the BB model as tenable in its current form, even Roger Penrose. He admitted that sometimes one has to re-examine current ideas in favour of ones that seem to be a better fit for the latest evidence. I think the universe is probably eternal although it probably takes on many incarnations and our particular one is what is happening now. |
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Post by jonjel on Mar 3, 2011 11:49:15 GMT 1
One question I have puzzled over (and no doubt will now be shot down in flames over) is this.
If the universe started with a big bang then all the matter emanated from one 'central' source.
If that is the case then why does the matter in the universe not follow inverse square law, i.e. the further from the source the less dense the matter?
Can that be explained without reams of mathematical formulae?
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Post by eamonnshute on Mar 3, 2011 11:54:15 GMT 1
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Post by eamonnshute on Mar 3, 2011 12:53:38 GMT 1
The programme doesn't actually discuss before the big bang, just the time since the BB, making the unjustified assumption that the BB is origin of the universe.
It was interesting that Newton came to the conclusion that the universe is infinite in size (12 minutes). I would agree with his conclusion, although I am not convinced by the reasoning given in the programme, which was that in a finite universe all stars would collapse into a single mass. The solar system is finite, but the sun and planets do not merge into one!
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Post by Progenitor A on Mar 3, 2011 13:52:56 GMT 1
One question I have puzzled over (and no doubt will now be shot down in flames over) is this. If the universe started with a big bang then all the matter emanated from one 'central' source. If that is the case then why does the matter in the universe not follow inverse square law, i.e. the further from the source the less dense the matter? Can that be explained without reams of mathematical formulae? Interesting In fact on this morning's programme it was stated that at one period in the expansion of the universe, gravity 'turned head over tails' and repelled rather than attracted (anti-gravity). That will have an effect upon the answer to your question (that I cannot provide). It was also stated that the rate of expansion has varied from time to time That also is interesting, because an accelaeration or deceleration requires a force, so somewhere ther is (or has been) a force acting on the universe (big force that!) |
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Post by abacus9900 on Mar 3, 2011 14:14:28 GMT 1
I think this just shows that our knowledge is incomplete, in fact, it will probably always be incomplete.
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Post by speakertoanimals on Mar 3, 2011 16:48:42 GMT 1
Because that is WRONG. It wasn't matter that started from some central point , and spread out (hence you'd expect 'edges' to be less dense), but space itself that started very small (but with matter equally-spread), and then expanded. Hence everywhere is pretty much like everywhere else because it always WAS.
The Big Bang happened EVERYWHERE, all at the same time, just that everywhere was a lot closer together back then...
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Post by abacus9900 on Mar 3, 2011 17:13:07 GMT 1
Because that is WRONG. It wasn't matter that started from some central point , and spread out (hence you'd expect 'edges' to be less dense), but space itself that started very small (but with matter equally-spread), and then expanded. Hence everywhere is pretty much like everywhere else because it always WAS. The Big Bang happened EVERYWHERE, all at the same time, just that everywhere was a lot closer together back then... Well, no, the universe as it is now cannot be the same as it was after the first few moments of the BB because in inflating it has evolved to become something different, even if the basic constituents are the same. |
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Post by Progenitor A on Mar 3, 2011 17:41:46 GMT 1
Because that is WRONG. It wasn't matter that started from some central point , and spread out (hence you'd expect 'edges' to be less dense), but space itself that started very small (but with matter equally-spread), and then expanded. Hence everywhere is pretty much like everywhere else because it always WAS. The Big Bang happened EVERYWHERE, all at the same time, just that everywhere was a lot closer together back then... Well, no, the universe as it is now cannot be the same as it was after the first few moments of the BB because in inflating it has evolved to become something different, even if the basic constituents are the same. Quite On the programme this morning they said one of the most important discoveries of cosmology in the '60's was the fact that the earliest universe was very much different than our our near-time universe and it is possible to track the evolution of the universe through these changes So well reasoned Abacus; Oxford , Cambridge and Durham cosmologists agree with you! |
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Post by abacus9900 on Mar 3, 2011 17:48:30 GMT 1
Thank you naymissus, but, er, can STA really be a physicist if she does not know that?
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Post by speakertoanimals on Mar 3, 2011 18:01:24 GMT 1
I never said it WAS idiot -- I said that everwhere THEN was much the same (as anyplace else THEN), whereas NOW, on average, everywhere NOW is pretty much the same as anywhere else NOW (apart from small perturbations like galaxies and clusters of galaxies.......)
God, some people don't care how stupid they have to pretend to be, if the supposed prize is supposedly finding me in error.............which makes them really idiotic.......................
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Post by Progenitor A on Mar 3, 2011 18:06:12 GMT 1
Thank you naymissus, but, er, can STA really be a physicist if she does not know that? ;D Don't be silly! Of course she is not a physicist! Physicists are numerate, don't speak gobbldegook and do not contradict themselves ;D |
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Post by speakertoanimals on Mar 3, 2011 18:46:28 GMT 1
Well, if you expect physicists to be super-human, and NEVER contradict themselves, no wonder you claim to not have found one...............
And if you knew ANY academics, you'd find that talking (seeming) gobbledegook is actually something we do quite often...................
Numerate? Who's the person round here who understand logs then......
Silly boys, playing their silly little games............
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Post by speakertoanimals on Mar 3, 2011 18:53:49 GMT 1
Not true, on ANY count.
STANDARD beginners level cosmology (General relativity) has a singularity at the Big Bang. Carefully stated, OUR universe began then, because if you take the singularity seriously, not clear how any information about anything earlier could have got through.
Once you begin to modify classical GR (string theory, loop quantum gravity), then you get the prospect of a before.
Actually, the previous stages of the universe concept is quite old, and various possibilities have been discussed. Just all gets a bit hung=up because we can't do quantum gravity yet, hence don't really have the tools to describe exactly what went on right back at OUR start, even if it wasn't THE start.................
Hence we have yet another thread spoiled by gross inaccuracies, ones that have been pointed out before as incorrect, yet ignored by the usual sock-puppets.............
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