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arXiv · 0902.3729

Uncertainty relation of mixed states by means of Wigner-Yanase-Dyson information

D. Li·X. Li·F. Wang·H. Huang·L. C. Kwek
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Abstract

The variance of an observable in a quantum state is usually used to describe Heisenberg uncertainty relation. For mixed states, the variance includes quantum uncertainty and classical uncertainty. By means of the skew information and the decomposition of the variance, a stronger uncertainty relation was presented by Luo in [Phys. Rev. A 72, 042110 (2005)]. In this paper, by using Wigner-Yanase-Dyson information which is a generalization of the skew information, we propose a general uncertainty relation of mixed states.

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D. Li, X. Li, F. Wang, H. Huang, L. C. Kwek. 2009-02-21. Uncertainty relation of mixed states by means of Wigner-Yanase-Dyson information. https://doi.org/10.1103/physreva.79.052106

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