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Renormalization-group running cosmologies and the generalized second law

R. Horvat
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Abstract

We explore some thermodynamical consequences of accelerated universes driven by a running cosmological constant (CC) from the renormalization group (RG). Application of the generalized second law (GSL) of gravitational thermodynamics to a framework where the running of the CC goes at the expense of energy transfer between vacuum and matter, strongly restricts the mass spectrum of a (hypothetical) theory controlling the CC running. We find that quantum effects driving the running of the CC should be dominated by a trans-planckian mass field, in marked contrast with the GUT-scale upper mass bound obtained by analyzing density perturbations for the running CC. The model shows compliance with the holographic principle.

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R. Horvat. 2007-03-22. Renormalization-group running cosmologies and the generalized second law. https://doi.org/10.1016/j.physletb.2007.03.037

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