Fast mixing of all-to-all quantum systems at high temperatures

Thiago Bergamaschi

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arXiv · 2606.26090

Fast mixing of all-to-all quantum systems at high temperatures

Thiago Bergamaschi

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Abstract

It is shown that arbitrary quantum $k$-local Hamiltonians with bounded strength interactions admit a quantum Gibbs sampler [CKG23] with a system-size independent spectral gap, at sufficiently high temperatures. This generalizes the existing quantum fast-mixing results beyond the geometrically-local setting. As a consequence, such systems admit fully-polynomial time quantum approximation algorithms for partition functions and global expectation values.

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Thiago Bergamaschi. 2026-06-24. Fast mixing of all-to-all quantum systems at high temperatures. https://arxiv.org/abs/2606.26090

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