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arXiv · 0708.0584

Experimental Falsification of Leggett's Non-Local Variable Model

Cyril Branciard·Alexander Ling·Nicolas Gisin·Christian Kurtsiefer·Antia Lamas-Linares·Valerio Scarani
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Abstract

Bell's theorem guarantees that no model based on local variables can reproduce quantum correlations. Also some models based on non-local variables, if subject to apparently "reasonable" constraints, may fail to reproduce quantum physics. In this paper, we introduce a family of inequalities, which allow testing Leggett's non-local model versus quantum physics, and which can be tested in an experiment without additional assumptions. Our experimental data falsify Leggett's model and are in agreement with quantum predictions.

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Cyril Branciard, Alexander Ling, Nicolas Gisin, Christian Kurtsiefer, Antia Lamas-Linares, Valerio Scarani. 2007-08-06. Experimental Falsification of Leggett's Non-Local Variable Model. https://doi.org/10.1103/physrevlett.99.210407

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