That’s computer science alongside with Church/Turing. Maths could have tried to claim it but they doubled down on formalism so they don’t deserve it.
That said though incompleteness follows from nothing but logical implication itself so it’s more fundamental than physics (try to imagine a physics without cause and effect that doesn’t get you cancelled because Boltzmann) and philosophy (find me a philosopher who wasn’t asleep during their logic lectures).
Yeah, I meant to say that the incompleteness theorem proves that math cannot be perfectly pure and fundamental. I don’t exactly care which field claims it, because I don’t like to encourage artificial boundaries between disciplines. It’s nice to use information theory results in physics :)
The other way around: As long as you accept that cause and effect are a thing, you must accept that there are things that are, fundamentally, uncomputable. And as our universe very much does seem to have cause and effect that’s a physical law, likewise is complexity theory. Differently put: God can’t sort a list with fewer than O(n log n) comparisons.
