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arXiv · 2504.15276

Improved Algorithms for Quantum MaxCut via Partially Entangled Matchings

Anuj Apte·Eunou Lee·Kunal Marwaha·Ojas Parekh·James Sud
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Abstract

We introduce a $0.611$-approximation algorithm for Quantum MaxCut and a $\frac{1+\sqrt{5}}{4} \approx 0.809$-approximation algorithm for the EPR Hamiltonian of [arXiv:2209.02589]. A novel ingredient in both of these algorithms is to partially entangle pairs of qubits associated to edges in a matching, while preserving the direction of their single-qubit Bloch vectors. This allows us to interpolate between product states and matching-based states with a tunable parameter.

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Anuj Apte, Eunou Lee, Kunal Marwaha, Ojas Parekh, James Sud. 2025-04-21. Improved Algorithms for Quantum MaxCut via Partially Entangled Matchings. https://arxiv.org/abs/2504.15276

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