I disagree that the rules just happen to be simple. Thinking in dynamical systems or evolutionary terms, a language and mental model of the universe just won’t stick around unless it’s useful. Imagining that the universe happens to be horribly complex, but has some emergent phenomena that happen to be simple, we’re almost inevitably going to think in those simpler terms and go “wow the universe is simple!”
Then if the foundation underlying those simple emergent concepts turns out to be horrible complex, maybe we get stuck with the foundations at some point. Or maybe simplicity is relative and a visitor from a different hypothetical universe would be astounded at all the shit we have to simulate because the answer isn’t just obvious.
Like how macroscopic objects are an emergent phenomenon, but they’re simple. Maybe the universe at a fundamental level follows some ultra convoluted string theory. Doesn’t matter for us, the same way that flipping a coin is 50-50 regardless of questions about foundational physics.
It’s taken a long time to develop the hierarchy of physical and mathematical concepts in which we can usefully describe much of the universe as simple. And those concepts, the best we have so far, still don’t tell the whole story.
> if the foundation underlying those simple emergent concepts turns out to be horrible complex
That is extremely unlikely. The simplicity of the universe is not just an artifact of our best theories, it appears to be baked into the very structure of those theories. If our current theories are even in the ballpark, then there are very few places that hidden complexity could possibly hide.
Take quantum randomness, for example. It used to be thought that the apparent randomness could just be papering over our ignorance of some hidden underlying mechanism, but it turns out that we can prove that this is not the case. We can eliminate entire classes of theories based on finite observations, and one of the classes that we can eliminate (with very high probability) is theories with high Kolmogorov complexity.
I assume you’re taking about the Bell experiments. Imagine that it’s the nonlocality side of things that ends up being correct. In that case, a full foundation of QM could be a nightmare.
Regardless, we don’t have a full unified theory of everything, so it seems premature to say we know how complex it’ll end up needing to be.
Also, the universe isn’t just an time evolution differential equation. It’s that, plus all the initial/boundary conditions. Saying the Kolmogorov complexity of the universe is small while only looking at the side that’s simplifiable seems circular.
Then if the foundation underlying those simple emergent concepts turns out to be horrible complex, maybe we get stuck with the foundations at some point. Or maybe simplicity is relative and a visitor from a different hypothetical universe would be astounded at all the shit we have to simulate because the answer isn’t just obvious.
Like how macroscopic objects are an emergent phenomenon, but they’re simple. Maybe the universe at a fundamental level follows some ultra convoluted string theory. Doesn’t matter for us, the same way that flipping a coin is 50-50 regardless of questions about foundational physics.
It’s taken a long time to develop the hierarchy of physical and mathematical concepts in which we can usefully describe much of the universe as simple. And those concepts, the best we have so far, still don’t tell the whole story.