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arXiv · 2504.10712

Improved approximation algorithms for the EPR Hamiltonian

Nathan Ju·Ansh Nagda
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Abstract

The EPR Hamiltonian is a family of 2-local quantum Hamiltonians introduced by King (arXiv:2209.02589). We introduce a polynomial time $\frac{1+\sqrt{5}}{4}\approx 0.809$-approximation algorithm for the problem of computing the ground energy of the EPR Hamiltonian, improving upon the previous state of the art of $0.72$ (arXiv:2410.15544). As a special case, this also implies a $\frac{1+\sqrt{5}}{4}$-approximation for Quantum Max Cut on bipartite instances, improving upon the approximation ratio of $3/4$ that one can infer in a relatively straightforward manner from the work of Lee and Parekh (arXiv:2401.03616).

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Nathan Ju, Ansh Nagda. 2025-04-14. Improved approximation algorithms for the EPR Hamiltonian. https://arxiv.org/abs/2504.10712

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