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Global information balance in quantum measurements

Francesco Buscemi·Masahito Hayashi·Michal Horodecki
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Abstract

We perform an information-theoretical analysis of quantum measurement processes and obtain the global information balance in quantum measurements, in the form of a closed chain equation for quantum mutual entropies. Our balance provides a tight and general entropic information-disturbance trade-off, and explains the physical mechanism underlying it. Finally, the single-outcome case, that is, the case of measurements with post-selection, is briefly discussed.

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Francesco Buscemi, Masahito Hayashi, Michal Horodecki. 2008-05-09. Global information balance in quantum measurements. https://doi.org/10.1103/physrevlett.100.210504

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