Roger Penrose, Stephen Hawking's teacher, and Paul Steinhardt, the Einstein chair at Princeton, both independently reject the big bang in part and go for a more cyclic model.
As Penrose points out CBR, cosmic background radiation, is 0.1% uninorm in all directions and looks like 3 degrees K radiation. That is as high entropy as it gets. The big bang would have had to be perfectly low entropy. Thus the theory in trouble with not only gravity, but the second law of thermodynamics. Yet two Nobel prizes have been handed out for the big bang.
For anyone who can think, this is troubling.
Not really, not so much as dark energy/dark matter that we had to invent to make the equations come out right. We're missing something bigly.
On the other hand there are particles (we postulate) so small and exist for so short a time that seem to hold atomic nuclei together that they cannot be individually detected by observation under our present understanding of physical laws (uncertainty principle). On the other hand the Hubble ultra deep space photo
(Wiki) reveals seemingly countless galaxies all with atoms composed of those tiny particles. A magnificent system to have come about on its own.
