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Non-additivity of Tsallis entropies and fluctuations of temperature

Christian Beck
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Abstract

We show that the non-additivity relation of the Tsallis entropies in nonextensive statistical mechanics has a simple physical interpretation for systems with fluctuating temperature or fluctuating energy dissipation rate. We also show that there is a distinguished dependence of the entropic index q on the spatial scale that makes the Tsallis entropies quasi-additive. Quasi-additivity implies that q is a strictly monotonously decreasing function of the spatial scale r, as indeed observed in various experiments.

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Christian Beck. 2001-05-18. Non-additivity of Tsallis entropies and fluctuations of temperature. https://doi.org/10.1209/epl%2Fi2002-00464-8

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