- #36
DrChinese
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Derek Potter said:To be quite clear about this, Bartlemann's socks are perfectly correlated with classical correlation. They were made as a pair and sent on their way. Alice and Bob's photons were made as a pair too, and were sent on their way. The difference is, the socks were sent as a mixed state |red>|blue> OR |blue>|red> but the photons are created (because of spatial symmetry) as a superposition of |H>|V> AND |V>|H>. |H> and |V> span the same state space as |a> and |a+90>, where a is an arbitrary angle, so the EPR correlation is maintained for just as long as the superposition does not collapse or otherwise decohere..
Almost everything here is incorrect as it pertains to the Delay Choice Entanglement Swapping (DCES, which is completely analogous to the DCQE in theoretical points). Bertlmann's socks IS classical (and has no bearing here anyway). But the entangled photon pair in DCES is not, and not only were they NOT made as a pair - they need never have existed at the same time. The EPR correlation does not even exist at the time the photons are measured and the related "collapse" occurs. That is done later.
I think my point in all this is: you are selling a naive version of these experiments. But they are complicated and touch on the outer edges of quantum weirdness. You deny that any collapse has occurred when measurement has taken place, yet in a different context you could say that is absolutely has because the outcome of an observation on entangled twins can be predicted with certainty. That does not imply an ongoing superposition at all!
What I am saying mimics QM itself: know the full context, you know the probabilities. The context need not be local or in a particular causal sequence. Why it works out that way is the mystery.