An infinitely dense particle exploding and forming the universe kinda sounds ridiculous. I buy that the expansion came from a single source, but what if that source is a tear in space, a leak of some sort. Would matter leaking from another dimension through a hole give us the same empirical data (red shift, etc)?
The first line in every economics textbook should be: "Marx was a stupid idiot". The second line should read "and the people who believe this nonsense are probably....."