From: hal@finney.org
Date: Fri Nov 26 1999 - 10:11:33 MST
Rob Harris, <rob@hbinternet.co.uk>, writes:
> Not. I had some duff knowledge in my head if you two are correct. I was
> certain that I'd heard from some trustworthy source that the galaxies that
> lie farthest from the point of origin of the universe are the oldest. I'll
> check that now.....
This is one of the most common misconceptions about the Big Bang, fostered
by countless animations which depict it as a conventional explosion,
a burst of light and energy spreading out into empty space.
As I understand the Big Bang model, there is no "point of origin"
of the universe. The universe is the same everywhere, and was born
everywhere at once. Consider the two-dimensional surface of a balloon
that starts at a point and then expands. Now point to the spot on that
surface that was the point of origin. You can't - the point of origin
is not on the surface, all parts of the surface are equally old.
Now conceptualize the surface as three dimensional, rather than two
dimensional, and we have our universe (in some models). It starts at
zero size and expands, but all parts of the universe are the same at
every moment. There is no preferred central location.
I don't know much about the inflation and bubble-universe models; maybe
they are non-homogeneous and specify that some parts of the universe
are different from others. But the basic Big Bang models I studied in
school are uniform.
Hal
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