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arXiv · 2610.05430

Strong Refutation for Random Quantum 3-SAT at Constant Density

Siu On Chan·Jeff Xu
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Abstract

We give a classical polynomial-time algorithm that strongly refutes random quantum $3$-SAT at sufficiently large constant constraint density, thereby disproving the quantum analogue of Feige's random $3$-SAT hypothesis. This stands in sharp contrast to classical random $3$-SAT, for which polynomial-time strong refutation is known only at constraint density $Δ\gtrsim n^{1/2}$. Although quantum $3$-SAT shares the pairwise-independence barrier of its classical counterpart, our SDP-based refutation overcomes this barrier by exploiting the noncommutativity of quantum constraints.

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Siu On Chan, Jeff Xu. 2026-10-04. Strong Refutation for Random Quantum 3-SAT at Constant Density. https://arxiv.org/abs/2610.05430

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