What should hidden variables explain?

[stevendaryl]

Mystical theories (theories which reject as the EPR principle of reality, as Reichenbach's common cause) can violate everything. But for a realistic, causal theory with fundamental Lorentz invariance (that means, where not only observables but everything should have Lorentz invariance) you can derive Einstein causality from the requirement that causality has to preserve Lorentz invariance.

And why would this be a problem if there is no causality? For mysticism causal loops are not a problem at all. There are only some correlations, that's all. Everything is somehow mystically correlated, this is sufficient, once the idea of a necessity of a causal explanation is rejected.

Well, if you have two theories that are empirically indistinguishable, then I don't see how you can call one "mystical" and the other not. The correlations implied by quantum mechanics are not arbitrary, they are very specific. It may be emotionally unsatisfying to have a theory that violates Einstein causality, but to go from there to "all bets are off, we might as well embrace magic and voodoo" is an over-reaction.

 

[Ilja]

Well, if you have two theories that are empirically indistinguishable, then I don't see how you can call one "mystical" and the other not. The correlations implied by quantum mechanics are not arbitrary, they are very specific. It may be emotionally unsatisfying to have a theory that violates Einstein causality, but to go from there to "all bets are off, we might as well embrace magic and voodoo" is an over-reaction.

Ok, we have three theories here:

1.) Fundamental realistic relativity, which gives Einstein causality and, then, Bell's inequality. This theory is empirically falsified by the known experiments.
2.) Realistic and causal Lorentz ether, or dBB interpretation of QM. It allows hidden causal influences into the future as defined by the preferred time coordinate. It does not allow to prove Bell's inequality, thus, is not empirically falsified by a violation of Bell's inequality.
3.) The immunization of (1) against this empirical falsification, by rejection of realism (EPR criterion) and causality (Reichenbach's common cause).

(1) and (2) are empirically distinguishable, by the violation of Bell's inequality, and have been empirically distinguished. (3) is mystical.

Feel free to explain me what is different between magic and voodoo, as long as they make predictions (astrology certainly does). The only remaining difference is that the numbers predicted by quantum theory fit better than those predicted by astrology, or at least we scientists think so. If this is fine with you, ok. But there was another difference between science and astrology in the past: Namely that science has constructed models of reality, models which have explained the numbers by realistic, causal influences.

 

[PeterDonis]

From Einstein causality one can derive Bell's inequality.

From a theory with a hidden preferred frame, which would allow hidden causal influences, you cannot derive Bell's inequality.

So what? There are also theories that do not have a hidden preferred frame, from which you cannot derive Bell's inequality (they predict violations of it). So why should I care that "Einstein causality" allows you to derive Bell's inequality? (That assumes that we even have a rigorous definition of "Einstein causality" plus a theory that exhibits it. As stevendaryl has already pointed out, "Einstein causality" is not the same as Lorentz invariance. See below.)

Fundamental realistic relativity

What theory are you talking about?

(1) and (2) are empirically distinguishable, by the violation of Bell's inequality, and have been empirically distinguished

I have closed this thread for moderation. Please PM me specific references for what you mean by "fundamental realistic relativity" if you want the thread reopened.