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arXiv · 1710.03062

Two-player entangled games are NP-hard

Anand Natarajan·Thomas Vidick
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Abstract

We show that the maximum success probability of players sharing quantum entanglement in a two-player game with classical questions of logarithmic length and classical answers of constant length is NP-hard to approximate to within constant factors. As a corollary, the inclusion $\mathrm{NEXP}\subseteq\mathrm{MIP}^*$, first shown in [IV12] with three provers, holds with two provers only. The proof is based on a simpler, improved analysis of the low-degree test Raz and Safra (STOC'97) against two entangled provers.

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Anand Natarajan, Thomas Vidick. 2017-10-09. Two-player entangled games are NP-hard. https://doi.org/10.4230/lipics.ccc.2018.20

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