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arXiv · 1905.01672

Toward a relative q-entropy

Nikolaos Kalogeropoulos
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Abstract

We address the question and related controversy of the formulation of the $q$-entropy, and its relative entropy counterpart, for models described by continuous (non-discrete) sets of variables. We notice that an $L_p$ normalized functional proposed by Lutwak-Yang-Zhang (LYZ), which is essentially a variation of a properly normalized relative R\'{e}nyi entropy up to a logarithm, has extremal properties that make it an attractive candidate which can be used to construct such a relative $q$-entropy. We comment on the extremizing probability distributions of this LYZ functional, its relation to the escort distributions, a generalized Fisher information and the corresponding Cram\'{e}r-Rao inequality. We point out potential physical implications of the LYZ entropic functional and of its extremal distributions.

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BibTeXRIS

Nikolaos Kalogeropoulos. 2019-05-05. Toward a relative q-entropy. https://doi.org/10.1016/j.physa.2019.123270

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