That’s false. Most of them still agree that Big Bang happened, it is just that the first extra small fraction of a second of Big Bang can’t be explained with our current understanding of physics, and there is still a lot of some unanswered questions about it.
Well apparently now astrophysicists are saying maybe the Big Bang didn’t happen. ¯_(ツ)_/¯
That’s false. Most of them still agree that Big Bang happened, it is just that the first extra small fraction of a second of Big Bang can’t be explained with our current understanding of physics, and there is still a lot of some unanswered questions about it.
But it is still the result of background radiation, which is caused by something.