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arXiv · 1908.05053

Strong unitary uncertainty relations

Bing Yu·Naihuan Jing·Xianqing Li-Jost
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Abstract

In this paper we provide a new set of uncertainty principles for unitary operators using a sequence of inequalities with the help of the geometric-arithmetic mean inequality. As these inequalities are "fine-grained" compared with the well-known Cauchy-Schwarz inequality, our framework naturally improves the results based on the latter. As such, the unitary uncertainty relations based on our method outperform the best known bound introduced in [Phys. Rev. Lett. 120, 230402 (2018)] to some extent. Explicit examples of unitary uncertainty relations are provided to back our claims.

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Bing Yu, Naihuan Jing, Xianqing Li-Jost. 2019-08-14. Strong unitary uncertainty relations. https://doi.org/10.1103/physreva.100.022116

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