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Additive entropy underlying the general composable entropy prescribed by thermodynamic meta-equilibrium

Ramandeep S. Johal
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Abstract

We consider the meta-equilibrium state of a composite system made up of independent subsystems satisfying the additive form of external constraints, as recently discussed by Abe [Phys. Rev. E {\bf 63}, 061105 (2001)]. We derive the additive entropy $S$ underlying a composable entropy $\tilde{S}$ by identifying the common intensive variable. The simplest form of composable entropy satisfies Tsallis-type nonadditivity and the most general composable form is interpreted as a monotonically increasing funtion $H$ of this simplest form. This is consistent with the observation that the meta-equilibrium can be equivalently described by the maximum of either $H[\tilde{S}]$ or $\tilde{S}$ and the intensive variable is same in both cases.

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Ramandeep S. Johal. 2003-06-27. Additive entropy underlying the general composable entropy prescribed by thermodynamic meta-equilibrium. https://doi.org/10.1016/s0375-9601(03)01055-7

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