The Universe 2

The Universe 2

But this does not mean that we are at the center of the universe, or at the center of its expansion. Aliens on planets millions of light-years away would observe the very same thing. This is because the universe has no center, just as the surface of a ball has no center. An observer at any point on an expanding ball would notice that all other points are moving away from him. The universe is like the surface of an expanding ball, except that where the surface of a ball has two dimensions, space-time has four! [TB] {SL}