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arXiv · 2303.01307

Notes on time entanglement and pseudo-entropy

K. Narayan·Hitesh K. Saini
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Abstract

Following arXiv:2210.12963 [hep-th], we investigate aspects of the time evolution operator regarded as a density operator and associated entanglement-like structures in various quantum systems. These involve timelike separations and generically lead to complex-valued entropy, although there are interesting real subfamilies. There are many parallels and close relations with reduced transition matrices and pseudo-entropy, which we discuss and clarify. For instance, a related quantity involves the time evolution operator along with a projection onto some initial state, which amounts to analysing pseudo-entropy for the initial state and its time-evolved final state.

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K. Narayan, Hitesh K. Saini. 2023-03-02. Notes on time entanglement and pseudo-entropy. https://arxiv.org/abs/2303.01307

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