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arXiv · 1411.7448

Rényi entropy uncertainty relation for successive projective measurements

Jun Zhang·Yang Zhang·Chang-shui Yu
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Abstract

We investigate the uncertainty principle for two successive projective measurements in terms of Rényi entropy based on a single quantum system. Our results cover a large family of the entropy (including the Shannon entropy) uncertainty relations with a lower optimal bound. We compare our relation with other formulations of the uncertainty principle in a two-spin observables measured on a pure quantum state of qubit. It is shown that the low bound of our uncertainty relation has better tightness.

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Jun Zhang, Yang Zhang, Chang-shui Yu. 2015-04-12. Rényi entropy uncertainty relation for successive projective measurements. https://doi.org/10.1007/s11128-015-0950-z

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