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arXiv · 1209.2016

The Gibbs paradox, Black hole entropy and the thermodynamics of isolated horizons

Andreas G. A. Pithis
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Abstract

This letter presents a new, solely thermodynamical argument for considering the states of the quantum isolated horizon of a black hole as distinguishable. We claim that only if the states are distinguishable, the thermodynamic entropy is an extensive quantity and can be well-defined. To show this, we make a comparison with a classical ideal gas system whose statistical description makes only sense if an additional 1/N!-factor is included in the state counting in order to cure the Gibbs paradox. The case of the statistical description of a quantum isolated horizon is elaborated, to make the claim evident.

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Andreas G. A. Pithis. 2013-04-15. The Gibbs paradox, Black hole entropy and the thermodynamics of isolated horizons. https://doi.org/10.1103/physrevd.87.084061

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