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Efficient Algorithms for Approximating Quantum Partition Functions

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 نشر من قبل Ryan Mann
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
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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 Netov{c}ny 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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