After reading so many threads here about it, I thought I would take a closer look at Bell's theorem. Consider the simple proof presented http://quantumtantra.com/bell2.html" [Broken], which I'll summarize below:(adsbygoogle = window.adsbygoogle || []).push({});

A light source produces twin state photons, and each photon of the pair goes through a polarizing filter oriented at some angle. If the two filters are oriented at 0 degrees, then it is found that the polarization of the two photons are perfectly correlated, i.e. the error rate is zero. A local realist might say that the two photons were given a definite polarization at the source. If the one of the filters is turned 30 degrees counter clockwise with respect to the other, then the error rate is found to be 25%. A local realist might say that the polarization of one out of every four photons that go through the 30-degree polarizer is changed from the initial polarization it had. So then if you turned both of the filters by 30 degrees in opposite direction, the maximum error rate you would get would be 25%+25%=50%, and the actual error rate would be even less because two simultaneous errors cancel each other out. So this is a version of Bell's inequality: the error rate at 60 degrees is less than or equal to 50%. Experimentally, this inequality has been disproven, as the error rate has been found to be 75%, so this local realist model doesn't seem to work.

My question is, what does this say about how strongly correlated entangled particles are? In the article, it is stated that local realism is disproved because of "the nature of the strong correlations observed". But that doesn't make sense to me. The local realist was expecting the particles to be correlated so strongly that even if you turned the filter by a large angle like 60 degrees, the error rate would still not exceed 50%. So isn't the experimental result that entanglement particles are more weakly correlated than allowed by local realism?

Or is it that the local realist would consider the 75% error rate at 60 degrees to be normal, but would be astounded that the error rate is so low at 30 degrees, so that the particles are more strongly correlated than local realism allows?

Any help would be greatly appreciated.

Thank You in Advance.

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# Does Bell's theorem imply stronger or weaker correlation?

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