Earlier quoted context omitted.
It's always been my understanding that the normal laws of physics don't work at big bang time as well. One thing I've wondered about is how people are so adamantly confident in the theory of the Big Bang in light of this. Is it simply because they don't like the alternatives, because they've never been heard an alternative, or is there a better reason?
The big bang theory explains a lot of stuff, like the cosmic microwave background, and the redshift of far-away galaxies.
Its usually given as an answer to "where did the universe come from".