[nocoolnametom]

When you say superdeterminism are you referring to something like Pilot Wave theory, where what appear to our measurements as probabilistic yet random interactions are merely expressions of a more complex yet non-random underlying system that we cannot, as yet, measure? (I don't even know if that's the proper description of the hypothesis.)

[xmcqdpt2]

Superdeterminism is simply the idea that all quantum experiments results could have been known before performing them, assuming a perfect knowledge of the state of the universe.

It's one of those things that could be true and explain all of QM but also is kind of a cop out. "Of course your two detectors are giving correlated results, they were tightly coupled 13.8 billion years ago and now they are forever linked like all things."

[consilient]

> Superdeterminism is simply the idea that all quantum experiments results could have been known before performing them, assuming a perfect knowledge of the state of the universe.

That's just determinism. Superdeterminism additionally posits that the results of those experiments are all correlated so as to make it appear to us as if local hidden variable theories were false. Pick the settings on two polarimeters for a Bell-type experiment by measuring the spins on photons emitted 10 billion years ago from two different galaxies, and you'll find (or rather, won't find, because it's being hidden from you) that they were arranged, long before the Earth was formed, just so as to trick you. The universe is conspiring against us, and the whole scientific project is a farce.

That, or superdeterminism is false.

[zmgsabst]

How is it a cop out?

We know two things:

- universe was small enough everything was tightly coupled

- non-local phenomena occur

Insisting that our beliefs reflect an ideology (eg, you can segregate off portions of reality to study in isolation) which seem contrary to observed reality (eg, the points above) is religion — not a scientific investigation of the universe.

[bowsamic]

Superdeterminism is a loophole in Bell's theorem that allows local hidden variables, so there could just be a fully deterministic theory that determines everything, including your detector settings in advanced. Classical physics has generally assumed that we at least have free choice to choose what to measure. If we don't, we can trivially retain classical gravity