Black hole cosmology suggests that the Milky Way and every other observable galaxy in our universe is contained within a black hole that formed in another, much larger, universe.
The theory challenges many fundamental models of the cosmos, including the idea that the Big Bang was the beginning of the universe.
It also provides the possibility that black holes within our own universe may be the boundaries to other universes, opening up a potential scenario for a multiverse.
Mine blown 🤯
The mass of the visible universe is apparently enough to make a black hole with an event horizon ten times larger than the visible universe’s. I don’t understand how that hasn’t happened already, but apparently it just doesn’t look like it’s happened (“unless…”).
It could totally have happened already and we just don’t notice, though there’s kind of a critical size where a black hole just gets infinitely big as adsorbing a stray hydrogen atom in the vacuum of space increases its radius enough to encompass multiple new hydrogen atoms and the whole thing just expands to encompass the entire universe. Kind of when everything is a black hole then nothing is a black hole sorta situation.