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arXiv · 2510.08484

Guess your neighbor's input: Quantum advantage in Feige's game

Simon Schmidt·Sigurd A. L. Storgaard·Michael Walter·Yuming Zhao
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Abstract

In this article, we study a nonlocal game with two questions and three answers per player, which was first considered by Feige in 1991, and show that there is quantum advantage in this game. We prove that the game is a robust self-test for the $3$-dimensional maximally entangled state. Furthermore, we show that the game can be seen as the "or" of two games that each do not have quantum advantage. Lastly, we investigate the behavior of the game with respect to parallel repetition in the classical, quantum and non-signalling case and obtain perfect parallel repetition of the non-signalling value if Feige's game is repeated an even amount of times.

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Simon Schmidt, Sigurd A. L. Storgaard, Michael Walter, Yuming Zhao. 2025-10-09. Guess your neighbor's input: Quantum advantage in Feige's game. https://arxiv.org/abs/2510.08484

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