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arXiv · 1510.09210

Quantum bounds on multiplayer linear games and device-independent witness of genuine tripartite entanglement

Gláucia Murta·Ravishankar Ramanathan·Natália Móller·Marcelo Terra Cunha
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Abstract

Here we study multiplayer linear games, a natural generalization of XOR games to multiple outcomes. We generalize a recently proposed efficiently computable bound, in terms of the norm of a game matrix, on the quantum value of 2-player games to linear games with $n$ players. As an example, we bound the quantum value of a generalization of the well-known CHSH game to $n$ players and $d$ outcomes. We also apply the bound to show in a simple manner that any nontrivial functional box, that could lead to trivialization of communication complexity in a multiparty scenario, cannot be realized in quantum mechanics. We then present a systematic method to derive device-independent witnesses of genuine tripartite entanglement.

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Gláucia Murta, Ravishankar Ramanathan, Natália Móller, Marcelo Terra Cunha. 2015-11-17. Quantum bounds on multiplayer linear games and device-independent witness of genuine tripartite entanglement. https://doi.org/10.1103/physreva.93.022305

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