After watching a Sam Harris conference a question came to my mind. Maybe it's been discussed several times, but I couldn't find any of that. The starting point is that, according to determinism, the state of the universe in instant $t_1$ could be theoretically determined knowing its state at a previous instant $t_0$. Well, let's take it for granted, which is not by the way. Let's go back in the past, where every instant is predetermined by the instant before. We may eventually arrive to a beginning, let's say the big bang. Question is: what if all the matter at a certain moment (the first moment) was in an homogeneous state ? If all the matter was compressed into a hot dense sphere of homogeneous matter, then how can determinism be true ? Otherwise, there must always be, in any moment, as much variables, as we find in a successive moment, otherwise it's not possible to determine the causes of the actual state of universe. Is then determinism compatible with big bang theory ?