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arXiv · 2601.21140

Efficient Algorithms for Weakly-Interacting Quantum Spin Systems

Ryan L. Mann·Gabriel Waite
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Abstract

We establish efficient algorithms for weakly-interacting quantum spin systems at arbitrary temperature. In particular, we obtain a fully polynomial-time approximation scheme for the partition function and an efficient approximate sampling scheme for the thermal distribution over a classical spin space. Our approach is based on the cluster expansion method and a standard reduction from approximate sampling to approximate counting.

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Ryan L. Mann, Gabriel Waite. 2026-01-29. Efficient Algorithms for Weakly-Interacting Quantum Spin Systems. https://doi.org/10.1103/45rz-42gr

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