@chrism Not an astrophysicist, but I think about this a lot. The idea of a cyclical universe conceptually makes a lot of sense, but it seems that the entities and forces that could make it happen are already known. If the Big Bang originated from a singularity, could it be a singularity at the center of a particularly massive black hole? Is it possible that black holes consolidate material until the Hawking radiation is not enough of a pressure release valve and then they explode? Would a large enough version of this obliterate anything nearby, making it appear as if the explosion was the beginning of everything? Could that process repeat again and again and again? These are just thought experiments my brain keeps me awake with at 4am, but I would love to have someone walk me through the evidence that invalidates that theory.