From: gsmith@concour.cs.concordia.ca (Gene Ward Smith)
Newsgroups: talk.religion.misc
Subject: Re: Origins of the Universe was (Clouds of hydrogen gas)
Keywords: We are all a product of the big-bang!
Date: 24 Jul 92 04:46:12 GMT
Organization: Centre Interuniversitaire en Calcul Mathematique Algebrique

In article <12371@inews.intel.com> pharvey@mipos3.intel.com (Paul
Harvey) writes:

>In article <4561@daily-planet.concordia.ca>
>gsmith@concour.cs.concordia.ca (Gene Ward Smith) writes:

>>1.  Recollapse *does not* mean cyclical.  It is far from clear how
>>a cyclical universe would work, and the big crunch does not necessarily lead
>>to another big bang.

>Yeah, but doesn't it seem unlikely that the big crunch would be stable?

I don't see why, a black hole is a singularity and it is stable.  The
trouble with big bang/big crunch singularities is that it is hard to
come up with any decent mathematical argument about what they ought to
do, but a big crunch singularity would seem to represent a high degree
of entropy in some sense.  I don't see any reason for regarding it as
likely to blow apart--gravity is attractive, not repulsive.

>Are you saying that assuming cycles of big-bang and big-crunch, that each cycle
>has higher entropy than the previous? If that is the case, then entropy
>death would still be the final result. Thus, an end.

I don't think such models have worked the bugs out, but this would
seem to be a problem--we wouldn't get a new clean universe like the
one we are in, but one with a grotty, irregular big bang with lot of
black holes and stuff flying out--if it manages to explode at all,
which I still don't see how it could do (compare the entropy at the
end of the old universe with that at the start of the new one, for
instance.)

>Right, but there seems to be a trend towards that direction. If sufficient
>mass is discovered, do you think it will change common culture, like the
>discovery by Europeans that the earth was round? 

I doubt it.  People right now usually know very little cosmology, and
why would this change?

>No! You mean Hawking is not the direct word from God?

He was offered the job, but turned it down.


>>Not true.  If there is a difference, what is it?

>Big-bang just takes us back to time zero which is a boundary. Who's to
>say what's on the other negative-time side? The problem really lies with
>the word begining and the causality it implies. Your basic chicken and
>egg problem. Which came first, the woman or the boy?

Well, this is just one formulation of the what is before the big bang
problem, or where did the BB come from.  And this has been thought on
by various people.  All very speculative, of course.

>But assuming that the Great Unified Field Theory, essentially
>the monotheistic God of science, is discovered, will the concept of entropy 
>still exist as one approaches time zero? At what point in time does the
>Second Law cease to exist?

Probably.  The Second Law is a statistical law of a very general
character, and it is pretty hard for any field theory to change it.
But *at* time zero is another problem.  Does a big crunch or big bang
singulariy have a definite entropy?  Just defining the entropy (in
some sense) of the universe as a whole is enough of a problem.
--
     Gene Ward Smith/Brahms Gang/CICMA/Concordia University 
                  gsmith@cs.concordia.ca