(December 20, 2021 at 7:46 pm)polymath257 Wrote: Sorry, I misspoke. We *can* detect causality violations. There are observations hat have been made that exclude *any* hiddent variable theories that are local.
Excluding local hidden variables doesn't really mean we ruled out causality... the possibility of global hidden variables is wide open. So, my question stands, how do you know that causality is violated in the first place ?
(December 20, 2021 at 7:46 pm)polymath257 Wrote: Classical physics is known to be wrong. That is why we currently use quantum physics. And quantum physics is NOT a causal theory: it is a probabilistic theory.
And we have done so: look up Aspect's experiment related to the EPR paradox. The observations violate Bell's inequalities which *must* be satisfied by any locally causal system.
I thought classical physics are a good approximation when we don't need all the precision of modern theories.? Newton's model of gravitation didn't become garbage because Einstein figured out a better model, we can still use Newtonian mechanics for a great deal of practical purposes.
Engineering mechanics is applied Newtonian mechanics for the most part, because a mechanical engineer doesn't really have to worry about crazy spacetime curves when designing mechanical systems......
Again, let's say there no local causal agent, force, etc. , does that also mean there is no causal agent altogether ???
If classical physics, being a good approximation of reality, preserves causality, it should be safe to say that the subtleties of causality at the quantum level are more due to incomplete information (uncertainty principle) than to a real violation of causality.