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Escort density operators and generalized quantum information measures

Jan Naudts
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Abstract

Parametrized families of density operators are studied. A generalization of the lower bound of Cramer and Rao is formulated. It involves escort density operators. The notion of phi-exponential family is introduced. This family, together with its escort, optimizes the generalized lower bound. It also satisfies a maximum entropy principle and exhibits a thermodynamic structure in which entropy and free energy are related by Legendre transform.

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Jan Naudts. 2004-07-30. Escort density operators and generalized quantum information measures. https://arxiv.org/abs/cond-mat/0407804

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