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arXiv · 2201.08886

Improved unitary uncertainty relations

Xiaoli Hu·Naihuan Jing
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Abstract

We derive strong variance-based uncertainty relations for arbitrary two and more unitary operators by re-examining the mathematical foundation of the uncertainty relation. This is achieved by strengthening the celebrated Cauchy-Schwarz inequality using a method of brackets and convex functions. The unitary uncertainty relations outperform several strong unitary uncertainty relations, notably better than some recent best lower bounds such as [Phys. Rev. Lett. 120, 230402 (2018)] and [Phys. Rev. A. 100, 022116 (2019)].

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Xiaoli Hu, Naihuan Jing. 2022-01-21. Improved unitary uncertainty relations. https://doi.org/10.1007/s11128-021-03396-3

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