[foxhill]

> But what about quantum computers? It would seem to me like their inherent nondeterministic behaviour would be an ideal fit for simulating other nondeterministic quantum systems.

true, but in this case now you either need a computer the size of the universe to simulate the universe in real time, or you can simulate a universe in (incredibly small) fractions of real time in a system less than the size of the universe.

this doesn't even get around the state-storage problem - storing the state of a simulated universe (assuming literally zero-overhead) takes the entirety of the universe too.

> In any case, it doesn't sound like they found any real theoretical limitation, just a practical one.

and therein lies the kicker :)