An Ideal Experiment

R. Casalbuoni, G. Domokos, Susan Kovesi-Domokos +1 more

João N. C. Especial

Bell inequalities applicable to non-ideal EPRB experiments are critical to the interpretation of experimental Bell tests. In this article it is shown that previous treatments of this subject are incorrect due to an implicit assumption and new inequalities are derived under general conditions. Published experimental evidence is reinterpreted under these results and found to be entirely compatible with local-realism, both, when experiments involve inefficient detection, if fair-sampling detection is assumed, as well as when experiments have nearly ideal detection and measurement crosstalk is taken into account.

Wu Xiao-Hua

Santos argued that quantum mechanical states which do violate the Bell inequalities are not physically realizable and local hidden-variable theories for quantum mechanics are still possible. We discuss the non-idealized experiment given by Santos, and show local-realism violation in such an experiment without requiring high efficiencies of the detectors and the polarization analyzers.

Pieter Kok

Karl Otto Greulich

Detecting non-locality requires almost ideal experimental conditions - ideal sources for entangled photon pairs and ideal detectors. Deviations from this ideal situation may critically hamper interpretations of experiments attempting to prove non-locality. Of two major known loopholes, the detector loophole is not yet unequivocally closed. Now another loophole emerges: When in such experiments down converting crystals with lasers as primary sources are used, exceeding threshold values in the Bell inequalities, i.e. their violation, can be caused by so far not fully recognized problems in the generation and detection of photon pairs. Taken together, nonlocality is still not yet unequivocally proven.