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arXiv · 2109.01345

A note on uncertainty relations of arbitrary N quantum channels

Qing-Hua Zhang·Jing-Feng Wu·Shao-Ming Fei
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Abstract

Uncertainty principle plays a vital role in quantum physics. The Wigner-Yanase skew information characterizes the uncertainty of an observable with respect to the measured state. We generalize the uncertainty relations for two quantum channels to arbitrary N quantum channels based on Wigner-Yanase skew information. We illustrate that these uncertainty inequalities are tighter than the existing ones by detailed examples. Especially, we also discuss the uncertainty relations for N unitary channels, which could be regarded as variance-based sum uncertainty relations with respect to any pure state.

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Qing-Hua Zhang, Jing-Feng Wu, Shao-Ming Fei. 2021-09-03. A note on uncertainty relations of arbitrary N quantum channels. https://doi.org/10.1088/1612-202x%2Fac1e30

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