Improved unitary uncertainty relations

• URL: http://arxiv.org/abs/2201.08886v1
• Date: Fri, 21 Jan 2022 21:02:08 GMT
• Title: Improved unitary uncertainty relations
• Authors: Xiaoli Hu and Naihuan Jing
• Abstract summary: We derive strong variance-based uncertainty relations for arbitrary two and more unitary operators. This is achieved by strengthening the celebrated Cauchy-Schwarz inequality using a method of brackets and convex functions.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• 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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