Why can't classical information be transmitted through quantum entanglement by measuring time between change events?

Question

If the effect of measurement in quantum entanglement occurs instantaneously why can't it be used to transmit classical information faster than light?

I'm based my question off this seemingly well cited Wikipedia article: http://en.wikipedia.org/wiki/Quantum_entanglement#cite_note-10

Edit: It would seem that my question should be more focused on why we can't use change as a method of data transmission.

possible duplicate of The choice of measurement basis on one half of an entangled state affects the other half. Can this be used to communicate faster than light? — Emilio Pisanty, Aug 14 '14 at 18:56
Reading that question - The premise of the answer is that we don't know what the resultant change would be on the other side. Should I change this question to ask why it is we can't use the fact that there is a change as a method of transferring information? — Dan O'Boyle, Aug 14 '14 at 18:58
Sure, that would help. There's a ton of similar questions, though, so have a good look at the search first. — Emilio Pisanty, Aug 14 '14 at 19:06
I would suggest that the EPR paradox can be phrased as "Humans are having a hard time differentiating quantum correlations from physical causality.". That's the whole point of "paradoxes": they offer clear evidence for our tendency to misinterpret the actual meaning of physical effects. — CuriousOne, Aug 14 '14 at 19:26
Who says there's change? How do Bob's possible measurements change compared to the case where Alice does not measure? — Emilio Pisanty, Aug 14 '14 at 19:44

score 0 · Answer 1 · edited Apr 13 '17 at 12:39

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Looking at other similar questions...

My understanding is that we can't use change events as a measure without knowing "when" measurements are made on one end we can't differentiate those changes from random changes (noise) on the other end.

Why can't quantum teleportation be used to transport information?

Improvements to my understanding are welcome!

edited Apr 13 '17 at 12:39

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answered Aug 14 '14 at 19:25

Dan O'Boyle

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You can basically understand the consequences of QM by looking at quantum cryptography: there is always a public channel in addition to the quantum channel. The public channel transmits the timing/result of the measurements on the source side. One can intercept the public channel without being noticed, but without the quantum channel's information, it's just a random string of numbers. One needs both channels to decrypt the transmission. – CuriousOne Aug 14 '14 at 19:40

Why can't classical information be transmitted through quantum entanglement by measuring time between change events?

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