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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Algorithm for nondestructive estimation of quantum relative entropy

Alexei Kaltchenko

Published Aug 24, 2004• 0 citations
Publisher

Abstract

We propose a new simple algorithm for non-destructive estimation of quantum relative entropy S(ρ||σ), where the density operators ρ and σ are defined on the same finite-dimensional Hilbert space but are otherwise completely unspecified (unknown). See text for formula.
DOI
10.1117/12.541901

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Motivated by the importance of entropy functions in quantum data compression, entanglement theory, and various quantum information-processing tasks, this study demonstrates how classical algorithms for entropy estimation can effectively contribute to the construction of quantum algorithms for universal quantum entropy estimation. Given two quantum i.i.d. sources with completely unknown density matrices, algorithms are developed for estimating quantum cross entropy and quantum relative entropy. These estimation techniques represent a quantum generalization of the classical algorithms by Lempel, Ziv, and Merhav.
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