Science and Astronomy Questions
Posted: 24 Nov 2019 05:54
midtskogen wrote:Source of the post Assuming that the Big Bang produced exactly equal amounts of matter and anti-matter, could the creation of anti-matter black holes be what shifted the balance and prevented everything from just annihilate into pure energy?
Interesting idea. Unfortunately I don't think this would solve the problem, because if say an equal amount of matter and antimatter collapsed into black holes, then there would still be an equal amount of matter and antimatter not in black holes, which presumably would still annihilate completely. Then we'd have either a universe full of nothing but black holes, or if those black holes were small enough to evaporate by now, a universe full of Hawking radiation. So we'd need some mechanism for having more antimatter to collapse into black holes than matter, which only shifts the problem. We also need this to happen over the right timescales and in such a way as to be consistent with observations.
This problem of why the universe is mostly full of matter rather than purely radiation from equal amount of matter and antimatter annihilating is called baryon asymmetry, and it's not fully understood. There are also other types of symmetries in particle physics, which were long held to be physical laws, but then discovered to be violated under certain conditions (CP-symmetry for example).