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arXiv · 2105.10658

Glued magic games self-test maximally entangled states

Laura Mančinska·Thor Gabelgaard Nielsen·Jitendra Prakash
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Abstract

Self-testing results allow us to infer the underlying quantum mechanical description of states and measurements from classical outputs produced by non-communicating parties. The standard definition of self-testing does not apply in situations when there are two or more inequivalent optimal strategies. To address this, we introduce the notion of self-testing convex combinations of reference strategies, which is a generalisation of self-testing to multiple strategies. We show that the Glued Magic Square game [Quantum 4 (2020), p. 346] self-tests a convex combination of two inequivalent strategies. As a corollary, we obtain that the Glued Magic square game self-tests two EPR pairs thus answering an open question from [Quantum 4 (2020), p. 346]. Our self-test is robust and extends to natural generalisations of the Glued Magic Square game.

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Laura Mančinska, Thor Gabelgaard Nielsen, Jitendra Prakash. 2021-05-22. Glued magic games self-test maximally entangled states. https://arxiv.org/abs/2105.10658

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