Imagine we had this incredibly powerful computer that can simulate our universe, and that we somehow knew the initial conditions of the big bang (or the planet earth) down to the exact detail. Fast forward the simulation we will uncover the many many secrets of the universe as we can see the cause and effect relationship established clearly (imagine it as a function with x as the time and y as the current state). Okay so what would happen if we fast forward it to the future and see, for example, yourself sitting in the same chair for the next 2 hours, but after seeing it you decide to jump to prove it wrong. I didn't know where to ask this reddit or the physics stackexhange (i was told on the sci fi platform to ask here) but this purely hypothetical situation has been bugging me for a while. The only probable solution i could see was
The simulation itself wouldn't be possible as in the quantum level particles do behave by chance so any outcome becomes equally likely (i personally thought it is determined by things we don't understand yet)
Edit 1: Okay maybe this wasn't the best SE to ask the question my bad, I'm fairly knew to SE as a whole and I'm not that regular either.
Edit 2: The point isn't simulating every atom in the universe, this would work with just Earth being simulated like I have mentioned but thanks I get it now. The problem with the infinite machines having to be simulated by the machine makes sense thank you. I think my problem was with the technical aspects of all this which now I have been referred to Determinism and its philosophy.