From what I have seen from reading and from a presentation Stephen hawking made is it true that the laws of physics affect the universe in the same way every time. If we knew how to account for every affect we could predict the future outcome of the universe, as you couldn't do a single situation prediction without accounting for everything in the universe. As every tiny effect would add up.
So, it makes sense, but is it true? Also please discuss the plausibility of a machine that can actually do this in the future if it is possible.