I haven’t looked at this in a few months but wish to add a comment. As far as science goes, it is never really settled. Big Bang or Big Bounce. I have a fondness for quantum mechanics and cut my scientific teeth on it in the 80’s (J. Phys. Chem. 1983, 87, 1438ff.), plus I find distasteful a singularity of energy at zero volume, and indeterminate physical laws left fully to Chance. With the quantom view, there is no initial singularity, and the universe expands from a finite volume where general relativity and the small scale physical laws are pre-existant. Even some stucture, such as massive black holes this early in the universe, might be explained. In addition, Big Bounce ekpyrotic (https://en.wikipedia.org/wiki/Ekpyrotic_universe) and cyclic models do not produce a multiverse, and while the random physical properties in a Big Bang expansion yields a universe truly left to Chance with the very properties of the universe determined by random Chance, this is not true with a Big Bounce. The uncertainty principle prevents an entirely predictive universe structure, but the laws of physics are invariant.

I find this much more appealing, not fully left to Chance. In any case, one still has to come to grips with the origin of a cyclic universe.