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arXiv · 2009.10605

Hidden non-Markovianity in open quantum systems

Daniel Burgarth·Paolo Facchi·Marilena Ligabò·Davide Lonigro
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Abstract

We show that non-Markovian open quantum systems can exhibit exact Markovian dynamics up to an arbitrarily long time; the non-Markovianity of such systems is thus perfectly "hidden", i.e. not experimentally detectable by looking at the reduced dynamics alone. This shows that non-Markovianity is physically undecidable and extremely counterintuitive, since its features can change at any time, without precursors. Some interesting examples are discussed.

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Daniel Burgarth, Paolo Facchi, Marilena Ligabò, Davide Lonigro. 2020-09-22. Hidden non-Markovianity in open quantum systems. https://doi.org/10.1103/physreva.103.012203

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