Possible Duplicate:
Did spacetime start with the Big bang?
on causality and The Big Bang Theory
Before the Big Bang
What's a compact scientific answer to question "(Why there is) / (what is before) the Big Bang?" Some fellow physics / science students ask question "what is before the Big Bang?" or alternatively "Why there is a Big Bang" (assuming the time dimension and hence 'before' is ill-defined at the event of Big Bang). We couldn't get any qualitative answer we universally agree on. Is there some compact way to answer this?
