When did the universe stop being a black hole?

Question

If inflationary cosmology is correct, then the observable universe was the size of a softball or a basketball or something of that order at the time inflation ended (~10^-32 seconds after the big bang). And all the mass of the observable universe was inside that little sphere.Which means that the mass was inside the Schwarzchild Radius for that amount of mass. Which means that the observable universe should have been a black hole.So: Was the observable universe a black hole? If not, why not? (ELI20 or so, please, if possible.)If it was a black hole, is it still? If not, how did we go from "was a black hole" to "is not a black hole", and when did we do so?If it is still a black hole, then... what? What are the consequences of that?

db48x · Accepted Answer

It never was a black hole. A black hole happens when the density of matter inside a volume is really large, but it also requires that the density of matter _outside_ be small. This may seem so trivial as to be irrelevant, but the big bang is what creates both space and time. All of the space and time are inside the universe, and this was true even when the universe was very small. With no outside, there was no black hole.