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Why quantum entanglement is considered to be active link between particles?

I am a layman trying to read into quantum mechanics. As I understand it quantum entanglement is an experimentally proven mechanism by which the quantum state of two particles become 100% correlated, that is, measuring the quantum state of one object causes you to know the quantum state of its entangled particle with 100% certainty (they're opposite).

Where I don't understand is why this is used to imply that information is "traveling", faster than light or not. Where is the intuition coming from that the correlation between two separated particles has anything to do with one particle effecting the other? For me, a much stronger explanation for why these two particles are correlated is that the entanglement itself effects the particles, that is, upon becoming entangled their quantum states are individually governed by some formula (as a function of time alone) where those formulas produce exact opposite results for each particle. Separating the particles doesn't have to change the formula, so if you measure one you know the other just because they must be opposite.

Yet from what I've read it's taken for granted that quantum entanglement = information is traveling from one to the other. Do we have a reason for thinking that? Have we shown that we can definitely modify the quantum state of one particle and therefore change the quantum state of its entangled partner, or anything else to show that information is traveling? It's the old question of "causation vs. correlation." In principle, the concept of measurement itself modifying the Universe itself (beyond any observer effects) strikes me as somewhat silly.

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marked as duplicate by Luboš Motl, Qmechanic, David Z Aug 19 '12 at 15:32

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    $\begingroup$ Hi Jeremy - it seems that the linked question addresses what you want to know, but if you don't agree, feel free to edit this to reflect what details you are looking for that the linked question doesn't provide, and I'll be happy to reopen it. (By the way, I don't believe "it's taken for granted that quantum entanglement = information is traveling from one to the other" is actually true. Those in the know would say no information is transferred.) $\endgroup$ – David Z Aug 19 '12 at 15:34