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arXiv · 2312.16765

Approximation algorithms for noncommutative CSPs

Eric Culf·Hamoon Mousavi·Taro Spirig
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Abstract

Noncommutative constraint satisfaction problems (NC-CSPs) are higher-dimensional operator extensions of classical CSPs. Despite their significance in quantum information, their approximability remains largely unexplored. A notable example of a noncommutative CSP that is not solvable in polynomial time is NC-Max-$3$-Cut. We present a $0.864$-approximation algorithm for this problem. Our approach extends to a broader class of both classical and noncommutative CSPs. We introduce three key concepts: approximate isometry, relative distribution, and $\ast$-anticommutation, which may be of independent interest.

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Eric Culf, Hamoon Mousavi, Taro Spirig. 2023-12-28. Approximation algorithms for noncommutative CSPs. https://arxiv.org/abs/2312.16765

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