system
Given the following post, respond as if you're commenting on Reddit:
human
How random is our universe?

What I mean by this question is say:
I turn back time a thousand years. Would everything happen exactly the same way?
Take it to the extreme, the Big Bang: Would our universe still end up looking like it is now?
gpt
It's not random at all; there are well-defined laws that govern how the state of the universe evolves from instant to instant. However, some of those well-defined laws are *probabilistic* rather than *deterministic.* That means it would be impossible to predict with certainty, even if you had perfect knowledge, how the universe would evolve from one instant to the next.

So the best anyone can really say is that if you did the last billion years (or whatever) over again, it's *possible* things would evolve in exactly the same way, but it's not *guaranteed,* and in fact one could reasonably say that it's vastly, vastly improbable.