[nadam]

Not too much, just one thing: If we could simulate the universe then of course there would be a simulation in the simulation, etc... And maybe there is a fundamental yet undiscovered 'law of computation' that a sufficiently complex simulation can embed itself only on a slower timescale, so even if everything is deterministic, we even theoretically cannot calculate fast enough to calculate the future.

[comex]

Embedding itself is one thing, but what about embedding a small portion of itself? Suppose the area to be simulated was merely the Solar System (with the rest faked), and the size of the computer far larger...

Very hypothetical of course :)