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arXiv · 2212.14472

On propagation of information in quantum many-body systems

Israel Michael Sigal·Jingxuan Zhang
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Abstract

We prove bounds on the minimal time for quantum messaging, propagation/creation of correlations, and control of states for general lattice quantum many-body systems. The proofs are based on a maximal velocity bound, which states that the many-body evolution stays, up to small leaking probability tails, within a light cone of the support of the initial conditions. This estimate is used to prove the light-cone approximation of dynamics and Lieb-Robinson-type bound, which in turn yield the results above. Our conditions cover long-range interactions. The main results of this paper as well as some key steps of the proofs were first presented in [36].

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Israel Michael Sigal, Jingxuan Zhang. 2022-12-29. On propagation of information in quantum many-body systems. https://arxiv.org/abs/2212.14472

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