I'm not an expert.
But, I believe that when the amount of matter in a black hole reaches a certain point, the density of the matter can get no greater, and a "rebound effect" of some sort occurs. It may have to do with "weak" nuclear forces or something. When you get the matter packed that densely, new forces become stronger than the gravitational pull of the black hole, and cause it to reverse direction with a big bang!
View Question Answers