So i have jut finish watching BBC Horizon Documentary about What happen before big bang. Documentary raises more question then answers. So i suppose main theory goes like this: there was nothing and then at some moment, for what ever reasons, there is a huge explosion and universe comes to existence and continues expanding. Am i right? Anyway, then comes along some scientis and says "No, No that is impossible how can something be created from nothing". So they think of brane, universes form black holes and so on. So lets assume that they are right about brane and that big bang was actually collision of two branes. Ok but this raises question where are branes located and how they come to existence. So for example : my house-->city-->country-->continent-->earth-->solar system-->our galaxy-->universe-->brane-->>x-->y-->z--> and so on and so on. So my question on is is origin of universe(branes or what ever) hole with no bottom? Any thoughts?