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arXiv · 1312.3216

General treatment for dark energy thermodynamics

H. H. B. Silva·R. Silva·R. S. Gonçalves·Zong-Hong Zhu·J. S. Alcaniz
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Abstract

In this work we discuss a general approach for the dark energy thermodynamics considering a varying equation of state (EoS) parameter of the type $ω(a)=ω_0+F(a)$ and taking into account the role of a non-zero chemical potential $μ$. We derive generalized expressions for the entropy density, chemical potential and dark energy temperature $T$ and use the positiveness of the entropy to impose thermodynamic bounds on the EoS parameter $ω(a)$. In particular, we find that a phantom-like behavior $ω(a)< -1$ is allowed only when the chemical potential assumes negative values ($μ<0$).

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H. H. B. Silva, R. Silva, R. S. Gonçalves, Zong-Hong Zhu, J. S. Alcaniz. 2013-12-11. General treatment for dark energy thermodynamics. https://doi.org/10.1103/physrevd.88.127302

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