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Anchored parallel repetition for nonlocal games

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 نشر من قبل Henry Yuen
 تاريخ النشر 2015
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We introduce a simple transformation on two-player nonlocal games, called anchoring, and prove an exponential-decay parallel repetition theorem for all anchored games in the setting of quantum entangled players. This transformation is inspired in part by the Feige-Kilian transformation (SICOMP 2000), and has the property that if the quantum value of the original game $G$ is $v$ then the quantum value of the anchored game $G_bot$ is $1 - (1 - alpha)^2 cdot (1 - v)$ where $alpha$ is a parameter of the transformation. In particular the anchored game has quantum value $1$ if and only if the original game $G$ has quantum value $1$. This provides the first gap amplification technique for general two-player nonlocal games that achieves exponential decay of the quantum value.



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