If we calculate Birth of Time then T= 0 or T ≠ 0. If Big Bang cause time then should we consider Big Bang time T = 0. But in real life we do have numbers beyond 0. Example : -1 , -2, -3 .....-1000 & so on. We represent space-time with numbers which are infinite on both side before 0 & after 0... so how space-time can be finite starting from Big Bang ? Can we consider Space-time was traveling in high dimension before Big Bang.