q: what caused the big bang?

bad quesadillas 

The Big Bang is fact because they know the exact location where it happened and can still detect the cosmic background radiation it caused.  That all dates from May 1964.  What caused the Big Bang and what happened during the first few minutes after is not known and never will be known because all the evidence was destroyed.

The correct answer is that we do not know. That is the honesty of science. It admits to what it does not know.

To assume, as you do, that something caused the Big Bang is incorrect. You have no evidence for this. That gets far too close to the audacious nonsense of an intelligent designer caused it to happen or, not much worse, that a god did it.

There are a number of difeerent hypotheses but without further research we cannot know which ones are the more likely to be correct and without some evidence we can never know for sure how it happened. One day we may know. The discovery could happen during our life times or in many generations to come. It may be something to which we shall never know the answer.

If we think of the "Big Bang", as being the start of what we call our universe , then it was simply a transition from that which already existed .

There was "existence" before "our universe" came along.

We may choose to think of existence /time beginning at the Big Bang -- but that is very unlikely.

And in case I don't get another chance --  I guess good bye to everyone . 

The Big Bang is a bunch of theorhetical numbers for something that never happened. Man has thus far failed to grasp the breadth of eternity and requires a starting point that doesn't exist. If you must have a starting point, it would be right now.

The first event can not have a cause or else it wouldn't be the first. If something caused the Big Bang, we can then ask want caused that. 

Cause (and causality) are not bound by the quantum realm which came into existence as a hot, dense energy state.  Expansion took over and the Big Bang began.  Is this any harder to believe than "God created the universe from nothing?"   I think not.

God spoke and there was a big bang?  (or maybe just a big flash of light)