All the more support for my assertion that seeing fall galaxies constitutes ‘seeing the edges of the universe’.
They’ve been providing light since the moment of their creation, we should be able to see them now. Please tell me the why you disagree on both of both of those.
Because, after inflation, the universe may have expanded to, say, 500 billion light-years (arbitrary number) in radius (…if “radius” truly has any meaning in this sense…). But light can only have traveled around 13 or 14 billion light years since the time of last scattering. Therefore, any galaxy 500 billion light years away, or 100 billion light years away, or 15 billion light years away, at that point in time has still not had enough time to send a photon to us. Get it?
**Toadspittle **has already answered, but I feel compelled to put my two cents in.
It’s easy to imagine the Big Bang like an explosion. Everything starts off at a point in space and goes flying off in all directions. Since nothing can travel faster than light, something that happens in one part of the explosion should be visible to all the other parts.
But that’s not a particularly good way to imagine the Big Bang. The Big Bang wasn’t an explosion IN space, but a rapid expansion OF space. And since the expansion of space isn’t limited by the speed of light, it’s possible (indeed, almost certain) for most of the universe to be carried away from our local neighborhood so rapidly that it’s outside our “light cone”: The light from those very distant galaxies hasn’t had time to reach us yet. (And, because the rate of expansion seems to be accelerating, it probably never will.)