Journal of Mathematical Physics

Properties of q-entropies

G. A. Raggio

Published Sep 1, 1995• 87 citations

Abstract

Basic properties of the q-entropy Sq[ρ]=(q−1)−1(1−tr(ρq)) (0<q≠1) for states of a quantum system are established: concavity, quasi-convexity, continuity, and failure of ‘‘additivity’’ and ‘‘subadditivity’’ for composite systems.

DOI: 10.1063/1.530920

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