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arXiv · 2205.09286

Tighter sum uncertainty relations via metric-adjusted skew information

Hui Li·Ting Gao·Fengli Yan
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Abstract

In this paper, we first provide three general norm inequalities, which are used to give new uncertainty relations of any finite observables and quantum channels via metric-adjusted skew information. The results are applicable to its special cases as Wigner-Yanase-Dyson skew information. In quantifying the uncertainty of channels, we discuss two types of lower bounds and compare the tightness between them, meanwhile, a tight lower bound is given. The uncertainty relations obtained by us are stronger than the existing ones. To illustrate our results, we give several specific examples.

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Hui Li, Ting Gao, Fengli Yan. 2022-05-19. Tighter sum uncertainty relations via metric-adjusted skew information. https://doi.org/10.1088/1402-4896%2Facaa13

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