I have several questions regarding the "big bounce" theory. It appears to be popular among LQG researchers. My questions are as as follows.
1) How one reconciles it with the fact that it is now experimentally established that the universe is expanding in an accelerating manner?
2) The entropy of the universe should have been very very low (maybe zero) at the time of the big bang/ big bounce. What was the entropy "before" that event? Was it even lower? If it was lower then doesn't that mean entropy decreases indefinitely? On the other hand if we accept the entropy was higher then doesn't that violate the second law of thermodynamics?
3) What observational evidence can confirm pre-bounce physics? According to GR there are some points near the bang/bounce where one simply can't easily define time in a meaningful way. Even for a quantum gravity theory, is it possible for any theory to extrapolate itself "before" the "bounce"? If there are no observational consequences after the bounce shouldn't one apply Occam's razor?