Don't know about disproven, I think its been abandoned for the most part though as physicists are working out a "theory of everything" aka "String Theory" which includes 11 dimensions and something about everything being made up of 'strings' which are now believed to actually be branes(membranes)...i used to know a bit more about it but the drugs sorta took care of that.

It turns out that when you have all the matter in the universe compressed into a space so small as the big bang states the laws of physics begin to break down. Do a google search you'll probably find out a lot more than I could post here.