Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site duke.UUCP
Path: utzoo!watmath!clyde!bonnie!akgua!mcnc!duke!crm
From: crm@duke.UUCP (Charlie Martin)
Newsgroups: net.astro.expert
Subject: Re: Where's the center of the universe?
Message-ID: <5869@duke.UUCP>
Date: Wed, 22-May-85 10:36:27 EDT
Article-I.D.: duke.5869
Posted: Wed May 22 10:36:27 1985
Date-Received: Fri, 24-May-85 06:12:56 EDT
References: <1544@amdahl.UUCP>
Reply-To: crm@duke.UUCP (Charlie Martin)
Distribution: net
Organization: Duke University
Lines: 38
Summary: 

In article <1544@amdahl.UUCP> gam@amdahl.UUCP (G A Moffett) writes:
>If the Universe is expanding from a common point, where is that
>point?  In particular, in what area of our sky is the direction
>of this point?
>-- 
>Gordon A. Moffett               ...!{ihnp4,cbosgd,sun}!amdahl!gam

Someone better qualified than I will probably give a wonderful technical
explanation, but in the mean time....

The big bang background radiation (i.e. 3degK microwave flux) appears to
be evenly distributed around the sky in all directions; that is, there
is no stronger point in any direction.  This could be interpreted to
mean that *we* are at the centre of the universe (and I'm surprized that
no Creationist has picked that one up.)

However, it is easier to explain (for me, anyway) that the universe as
we see it is a hypersurface which is expanding is some n-space (say
4-space for tradition, although there are arguments for lots of other
spaces).  Then we could see the space expanding away in all directions
evenly because the actual point from which it is expanding is not in our
perceived space at all.

This is all pretty loose in these words, but it can be seen with a nice
analogy: suppose we were Flatlanders on the surface of a sphere in
3-space (these are actually spherelanders, but you know what I mean).
If the sphere expands uniformly in 3-space (like a balloon being
inflated) then *each* flatlander will see every other point move away
from them while they stand still -- and each will perceive no
"direction" from which the expansion of the universe is centered.

So the direction you are asking about seems to be backwards in time to
the Big Event -- or at least off in some direction outside of our
space.
-- 

			Charlie Martin
			(...mcnc!duke!crm)