[scott_s]

There are situations in nature where our models are NP-hard. Whether or not this is the same as saying that nature itself performs those computations is, I think, tied into the question of whether or not our Universe is a simulation.

[elektronjunge]

If natures models reduce to our NP-hard models which they would if our models are accurate, that is to say if and only if there is some computation that is NP-hard (which means that it is proven to not have a polynomial time solution unless P=NP) that nature can solve in polynomial time and we have proven that P must equal NP.

[scott_s]

Our models are not (necessarily) nature. The map is not the territory.

[baddox]

I've never read any explanation of the Universe-as-a-simulation concept that I have understood. If the Universe isn't a simulation, then what is it?

[scott_s]

I don't know - but answering a question with "I don't know" does not imply that we should pick an answer just because we don't have a good answer.

[baddox]

I think it's pretty important to convey or at least have a clear definition of the concept of the Universe being a simulation.