3 upvotes, 2 direct replies (showing 2)
View submission: Ask Anything Wednesday - Physics, Astronomy, Earth and Planetary Science
What is the earliest age of the universe at which a black hole can theoretically be formed?
Comment by [deleted] at 13/09/2023 at 20:09 UTC
4 upvotes, 0 direct replies
I don't know the subject but I know the term Primordial black hole, a theory about very early formation of black holes: https://en.wikipedia.org/wiki/Primordial_black_hole[1] - one second after big bang, it says! But they have never been confirmed.
1: https://en.wikipedia.org/wiki/Primordial_black_hole
Comment by nivlark at 13/09/2023 at 16:49 UTC
4 upvotes, 1 direct replies
There's nothing that says a black hole couldn't form at arbitrarily early times. But the only known mechanism by which one actually forms is the collapse of a massive star, which couldn't happen until the first stars formed around a hundred million years after the Big Bang.
There may well be other mechanisms that formed black holes earlier, for example the direct collapse of massive gas clouds has been suggested as the origin of the supermassive black holes found at the centres of galaxies, but currently these are all hypothetical.