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arXiv · 2510.22867

Universal Decay of Mutual Information and Conditional Mutual Information in Gapped Pure- and Mixed-State Quantum Matter

Jinmin Yi·Kangle Li·Chuan Liu·Zixuan Li·Liujun Zou
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Abstract

For spin and fermionic systems in any spatial dimension, we establish that the superpolynomial decay behavior of mutual information and conditional mutual information is a universal property of gapped pure- and mixed-state phases; i.e., all systems in such a phase possess this property if one system in this phase possesses this property. We further demonstrate that the (conditional) mutual information indeed decays superpolynomially in a large class of phases, including chiral phases. As a by-product, we sharpen the notion of mixed-state phases.

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Jinmin Yi, Kangle Li, Chuan Liu, Zixuan Li, Liujun Zou. 2025-10-26. Universal Decay of Mutual Information and Conditional Mutual Information in Gapped Pure- and Mixed-State Quantum Matter. https://doi.org/10.1103/mqp8-y1m7

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