The “Big bang theory” is nonsense.
All of the visible evidence points to the steady, uniform expansion called for in the Bible.
.
there was no air...therefore there was no audible bang. the term was used by a noted astronomer, Fred Hoyle, as a denigration of the expansion theory...but it was then used to describe that expansion theory almost as snarky homage to the guy who didn’t believe in it...(Einstein also did not want an expanding universe...he wanted for all the world for the Universe to be steady state)