It is not that difficult. A event occured call it what ever the hell you wish to call it:
a. singularity
b. quantum event
c. quantum fluctuation
d. Big Bang
e. Genesis for all I care.
Ok.. you with me on that?
Now once this event occured space/time and the universe began to exist.
My only point is that once this event occured the universe came into existance. So we can attribute the universes beginning to the : a ..b...c..d..or e..
This says nothing of if it was caused by God, the Devil or super intelligent aliens. Or if it was even caused at all, for all we know it just just happened all by itself. My point is there is as of this date any one in the scientific community that can say for sure that the universe is "uncaused". It is postulated and theorized that it may be uncaused. But it is still possible that it could of had a cause.