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Here's a hidden gem:

"The key point is that seeing a hidden variable’s history would effectively let us simulate non- collapsing measurements."

This fact allows one to dismiss all hidden-variables theories (including Bohm's of course) as having no metaphysical relevance. Hidden variables are the invisible pink unicorn of physics. If you can't measure it, it doesn't exist. Deal with it.




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I don't think you understand the quantum mechanical concept of hidden variablea. They are not at all the same as classical unknowns.


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> Hidden variables have more meaning to me in sociological and psychological systems.

Then you are talking about something completely different than the matter at hand. The term "hidden variable theory" has a specific technical meaning in quantum mechanics:

http://en.wikipedia.org/wiki/Hidden_variable_theory

> there exists a way to reason about systems that contain hidden variables, we just do not know it yet

The whole point here is that we can definitively eliminate that possibility. If it were possible to reconstruct the values of hidden variables in quantum mechanics then it would be possible to simulate collapse-free measurement, and the entire theory would be wrong.


In Quantum Mechanics, hidden variable theories are ones that reduce QM to a probabilistic (or even deterministic) theory that is local and causal.


Not necessarily local. In fact, Bell's theorem shows that local hidden variables theories are not possible (to be technically correct, that all local hidden variables theories produce predictions that are at odds with experiment). The reason Aaronson's statement is cool is because it allows us to eliminate ALL hidden variables theories -- local and non-local -- on metaphysical grounds (i.e. by Occam's razor). Yes, you can produce (non-local) hidden-variables theories whose predictions are consistent with experiment. But if you could assign historical values to those variables that would be tantamount to performing collapse-free measurement and that is (almost certainly) not possible.




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