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Re:Researchers Advance 'Quantum Teleportation' by EGreg on Sunday November 23, 2014 @10:27AM (#8648978)
I thought something like pilot wave theory gets around Bell's theorem. Also since Bell's theorem makes an assumption of local realism and nothing-goes-faster-than-light, how does the description of entanglement as "spooky action at a distance" not violate those?

Sheesh, these are awfully handwavy questions for someone who was in a math ph D program. I should really sit sown and learn quantum mechanics for a while with the math. How long do you think it would take to reason intelligently about it? Going by what Feynman said, maybe I can't.

Re:Researchers Advance 'Quantum Teleportation' by inclemnet on Sunday November 23, 2014 @11:21AM (#8649105)
> I thought something like pilot wave theory gets around Bell's theorem

Bell's theorem remains true, but pilot wave theory achieves the quantum results by sacrificing locality instead of hidden variables.

> how does the description of entanglement as "spooky action at a distance" not violate those?

It's just a name, and an old one at that. I suppose if you ascribe it to non-locality then it really does involve something FTL on some level, but even with a standard locality-preserving, no hidden variables theory, no information travels faster than light so you don't actually hit a FTL problem. The strange thing is that the quantum state appears to behave consistently regardless of its spatial extent, which is weird.

> How long do you think it would take to reason intelligently about it?

I would have thought that someone in a PhD mathematics program would be well equipped to understand the mathematics - maybe the hard part is finding a good resource that takes things in a good order. I'm afraid I can't really recommend anything, though Feynman's stuff is probably good.