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arXiv · 1705.07396

Variance-based uncertainty relation for incompatible observers

Xiao Zheng·Guo-Feng Zhang
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Abstract

Based on mixedness definition as M=1-tr(\r{ho}^2), we obtain a new variance-based uncertainty equality along with an inequality for Hermitian operators of a single-qubit system. The obtained uncertainty equality can be used as a measure of the system mixedness. A qubit system with feedback control is also exploited to demonstrate the new uncertainty.

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Xiao Zheng, Guo-Feng Zhang. 2017-05-21. Variance-based uncertainty relation for incompatible observers. https://arxiv.org/abs/1705.07396

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