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arXiv · 2205.03193

Probability density functions of quantum mechanical observable uncertainties

Lin Zhang·Jinping Huang·Jiamei Wang·Shao-Ming Fei
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Abstract

We study the uncertainties of quantum mechanical observables, quantified by the standard deviation (square root of variance) in Haar-distributed random pure states. We derive analytically the probability density functions (PDFs) of the uncertainties of arbitrary qubit observables. Based on these PDFs, the uncertainty regions of the observables are characterized by the supports of the PDFs. The state-independent uncertainty relations are then transformed into the optimization problems over uncertainty regions, which opens a new vista for studying state independent uncertainty relations. Our results may be generalized to multiple observable case in higher dimensional spaces.

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Lin Zhang, Jinping Huang, Jiamei Wang, Shao-Ming Fei. 2022-05-06. Probability density functions of quantum mechanical observable uncertainties. https://doi.org/10.1088/1572-9494%2Fac6b93

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