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arXiv · 1501.04906

Cosmological evolution of the gravitational entropy of the large-scale structure

Giovanni Marozzi·Jean-Philippe Uzan·Obinna Umeh·Chris Clarkson
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Abstract

We consider the entropy associated with the large-scale structure of the Universe in the linear regime, where the Universe can be described by a perturbed Friedmann-Lemaître spacetime. In particular, we compare two different definitions proposed in the literature for the entropy using a spatial averaging prescription. For one definition, the entropy of the large-scale structure for a given comoving volume always grows with time, both for a CDM and a $Λ$CDM model. In particular, while it diverges for a CDM model, it saturates to a constant value in the presence of a cosmological constant. The use of a light-cone averaging prescription in the context of the evaluation of the entropy is also discussed.

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Giovanni Marozzi, Jean-Philippe Uzan, Obinna Umeh, Chris Clarkson. 2015-09-01. Cosmological evolution of the gravitational entropy of the large-scale structure. https://doi.org/10.1007/s10714-015-1955-8

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