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arXiv · 1704.08223

Communication games reveal preparation contextuality

Alley Hameedi·Armin Tavakoli·Breno Marques·Mohamed Bourennane
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Abstract

A communication game consists of distributed parties attempting to jointly complete a task with restricted communication. Such games are useful tools for studying limitations of physical theories. A theory exhibits preparation contextuality whenever its predictions cannot be explained by a preparation noncontextual model. Here, we show that communication games performed in operational theories reveal the preparation contextuality of that theory. For statistics obtained in a particular family of communication games, we show a direct correspondance with correlations in space-like separated events obeying the no-signaling principle. Using this, we prove that all mixed quantum states of any finite dimension are preparation contextual. We report on an experimental realization of a communication game involving three-level quantum systems from which we observe a strong violation of the constraints of preparation noncontextuality.

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Alley Hameedi, Armin Tavakoli, Breno Marques, Mohamed Bourennane. 2017-11-18. Communication games reveal preparation contextuality. https://doi.org/10.1103/physrevlett.119.220402

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