On Fri, 10 Nov 2000, Doug Pensinger wrote:
> The model most often used to describe the expanding universe is the "skin" of
> a balloon. How literal is that example?
Not very.
It works as a skin of a balloon if you keep firmly in mind that there
is *nothing* inside or outside the balloon. Space itself, the surface,
is what's expanding; stuff isn't moving through it as a result of the
expansion.
> Does all matter expand away from a
> point of origin leaving a void in the center?
No.
A better analogy, and one that's being used more frequently nowadays,
is a rising loaf of raisin bread, with galaxies as the raisins; the thing
as a whole gets bigger, and the raisins get farther apart, but they don't
expand themselves. Now you just need a loaf of raisin bread with no
center or edges, and you've more or less got the universe.
--
Andrea Leistra [EMAIL PROTECTED]
"If you can keep your head while all those about you are
losing theirs, perhaps you have misunderstood the situation."
-- Daniel Keys Moran, _The Long Run_
