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Average Entropy of a Subsystem from its Average Tsallis Entropy

L. C. Malacarne·R. S. Mendes·E. K. Lenzi
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Abstract

In the nonextensive Tsallis scenario, Page's conjecture for the average entropy of a subsystem[Phys. Rev. Lett. {\bf 71}, 1291(1993)] as well as its demonstration are generalized, i.e., when a pure quantum system, whose Hilbert space dimension is $mn$, is considered, the average Tsallis entropy of an $m$-dimensional subsystem is obtained. This demonstration is expected to be useful to study systems where the usual entropy does not give satisfactory results.

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L. C. Malacarne, R. S. Mendes, E. K. Lenzi. 2002-01-15. Average Entropy of a Subsystem from its Average Tsallis Entropy. https://doi.org/10.1103/physreve.65.046131

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