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arXiv · 2205.04805

Weisfeiler-Leman Invariant Promise Valued CSPs

Libor Barto·Silvia Butti
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Abstract

In a recent line of work, Butti and Dalmau have shown that a fixed-template Constraint Satisfaction Problem is solvable by a certain natural linear programming relaxation (equivalent to the basic linear programming relaxation) if and only if it is solvable on a certain distributed network, and this happens if and only if its set of Yes instances is closed under Weisfeiler-Leman equivalence. We generalize this result to the much broader framework of fixed-template Promise Valued Constraint Satisfaction Problems. Moreover, we show that two commonly used linear programming relaxations are no longer equivalent in this broader framework.

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Libor Barto, Silvia Butti. 2022-05-10. Weisfeiler-Leman Invariant Promise Valued CSPs. https://arxiv.org/abs/2205.04805

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