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arXiv · 2001.03421

Error bounds for constrained dynamics in gapped quantum systems: Rigorous results and generalizations

Zongping Gong·Nobuyuki Yoshioka·Naoyuki Shibata·Ryusuke Hamazaki
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Abstract

In arXiv:2001.03419 we introduce a universal error bound for constrained unitary dynamics within a well-gapped energy band of an isolated quantum system. Here, we provide the full details on the derivation of the bound. In addition, we generalize the result to isolated quantum many-body systems by employing the local Schrieffer-Wolff transformation, obtaining an error bound that grows polynomially in time. We also generalize the result to Markovian open quantum systems and quantitatively explain the quantum Zeno effect.

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BibTeXRIS

Zongping Gong, Nobuyuki Yoshioka, Naoyuki Shibata, Ryusuke Hamazaki. 2020-01-03. Error bounds for constrained dynamics in gapped quantum systems: Rigorous results and generalizations. https://doi.org/10.1103/physreva.101.052122

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