# Testing Bell's inequality with cosmic photons: closing the setting-independence loophole.

@article{Gallicchio2014TestingBI, title={Testing Bell's inequality with cosmic photons: closing the setting-independence loophole.}, author={Jason Richard Gallicchio and Andrew S. Friedman and David I. Kaiser}, journal={Physical review letters}, year={2014}, volume={112 11}, pages={ 110405 } }

We propose a practical scheme to use photons from causally disconnected cosmic sources to set the detectors in an experimental test of Bell's inequality. In current experiments, with settings determined by quantum random number generators, only a small amount of correlation between detector settings and local hidden variables, established less than a millisecond before each experiment, would suffice to mimic the predictions of quantum mechanics. By setting the detectors using pairs of quasars…

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