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arXiv · 1706.02130

Self-testing properties of Gisin's elegant Bell inequality

Ole Andersson·Piotr Badziąg·Ingemar Bengtsson·Irina Dumitru·Adán Cabello
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Abstract

An experiment in which the Clauser-Horne-Shimony-Holt inequality is maximally violated is self-testing (i.e., it certifies in a device-independent way both the state and the measurements). We prove that an experiment maximally violating Gisin's elegant Bell inequality is not similarly self-testing. The reason can be traced back to the problem of distinguishing an operator from its complex conjugate. We provide a complete and explicit characterization of all scenarios in which the elegant Bell inequality is maximally violated. This enables us to see exactly how the problem plays out.

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Ole Andersson, Piotr Badziąg, Ingemar Bengtsson, Irina Dumitru, Adán Cabello. 2017-10-05. Self-testing properties of Gisin's elegant Bell inequality. https://doi.org/10.1103/physreva.96.032119

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