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arXiv · 2608.16439

Optimal bounds on the classical value of the repeated CHSH game

Andris Ambainis
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Abstract

We show that the maximum winning probability in the repeated CHSH game for classical strategies is at most $\left(\frac{1+\sqrt{5}}{4}\right)^n$. Together with a matching lower bound by Barak et al. (FOCS'2008), this determines the asymptotic value of the repeated CHSH game exactly. We also show that, if an XOR game has a gap between classical and quantum values, there is also a gap between the asymptotic values for the repeated game.

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Andris Ambainis. 2026-08-17. Optimal bounds on the classical value of the repeated CHSH game. https://arxiv.org/abs/2608.16439

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