Re: Thrust of Big Bang

In article
<5f383654-6023-4fc3-804c-d365ec0b7d1c@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
stork <Todd.Bandrowsky@xxxxxxxxx> writes:

If I look at a simple chronology for the Big Bang, I see that there's
a period between the advent of the big bang and then maybe a few
million years out where there's enough hydrogen and helium gas for the
first stars to form. It's immensely fascinating, and I have a
question is this.

Where's the gravity?

What keeps all of this newly created matter from sinking back into a
singularity, black hole style, to begin with?

Nothing. It WILL recollapse---if the matter density is high enough.
However, it will not necessarily recollapse---if the matter density is
low enough. Think of a rocket fired from Earth---it will eventually
fall back down, unless escape velocity is reached, in which case it
won't. The gravity is still there, but if the escape velocity is
reached, it will never win out.

.