If the big bang created the universe what created the big bang?
"The Big Bang" is a viewpoint that embraces that our reality (essentially physics - and all that entails) seems to have a beginning point in space and time (indeed, space and time being an aspect of physics). Our reality had a starting point.
"WHAT" may have existed "BEFORE" that (both issues being irrelevant since our reality was not before that and remember there is no time before time existed) is simply unknown and probably unknowable since we can only know OUR reality, we have no clue what other realities MAY have existed at that time or before that time or even in our time. Some theoretical physicists hold that we live in a multiverse, with perhaps hundreds, thousands, millions, billions, trillions of other realities all co-existing but all unaware of each other since each has its own reality and only exists in that.
Physicist reject that because we don't (and probably can't) know what Reality or Realities existed does not mean ERGO God did it. That would be giving an answer that simply has no evidence in physics (indeed, theists hold that God is OUTSIDE physics). The question is unanswered and likely unanswerable for scientists. Theists may hold that God did it - and no physicists would hold that's impossible, only that physics doesn't prove that.
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