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arXiv · 2509.19966

No Quantum Advantage in Decoded Quantum Interferometry for MaxCut

Ojas Parekh
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Abstract

Decoded Quantum Interferometry (DQI) is a framework for approximating special kinds of discrete optimization problems that relies on problem structure in a way that sets it apart from other classical or quantum approaches. We show that the instances of MaxCut on which DQI attains a nontrivial asymptotic approximation guarantee are solvable exactly in classical polynomial time. We include a streamlined exposition of DQI tailored for MaxCut that relies on elementary graph theory instead of coding theory to motivate and explain the algorithm.

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Ojas Parekh. 2025-09-24. No Quantum Advantage in Decoded Quantum Interferometry for MaxCut. https://arxiv.org/abs/2509.19966

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