Oh yes time is necessary for the universe to exist.<quoted text>OK, progress. I take that to mean you agree that we cannot know anything about t = 0. I do disagree though that we would prove anything about 't = 0' if we succeeded in a "0 time" condition because who can say if time (motion) is neccessary for existance? No one can.
There would be no motion , and energy requires motion.
Motion requires time and without motion there is only a singularity lacking dimension.
Infinite density is , zero time zero motion zero space zero heat.
Absolute zero, or Pandora's box is a unsolvable mystery.
But it doesn't mean it had a uncaused causer of causes.
It just means it's paradoxical and counter intuitive to human reasoning. t=0 is the opposite of infinity.
The answer is "The universe simply always was, because there was no time before it." AND "Without a time before, the notion of "cause" no longer applies."