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arXiv · 2004.11568

Efficient Algorithms for Approximating Quantum Partition Functions

Ryan L. Mann·Tyler Helmuth
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Abstract

We establish a polynomial-time approximation algorithm for partition functions of quantum spin models at high temperature. Our algorithm is based on the quantum cluster expansion of Neto\v{c}n\'y and Redig and the cluster expansion approach to designing algorithms due to Helmuth, Perkins, and Regts. Similar results have previously been obtained by related methods, and our main contribution is a simple and slightly sharper analysis for the case of pairwise interactions on bounded-degree graphs.

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Ryan L. Mann, Tyler Helmuth. 2020-04-24. Efficient Algorithms for Approximating Quantum Partition Functions. https://doi.org/10.1063/5.0013689

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