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arXiv · 1412.2618

A violation of the covariant entropy bound?

Ali Masoumi·Samir D. Mathur
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Abstract

Several arguments suggest that the entropy density at high energy density $ρ$ should be given by the expression $s=K\sqrt{ρ/G}$, where $K$ is a constant of order unity. On the other hand the covariant entropy bound requires that the entropy on a light sheet be bounded by $A/4G$, where $A$ is the area of the boundary of the sheet. We find that in a suitably chosen cosmological geometry, the above expression for $s$ violates the covariant entropy bound. We consider different possible explanations for this fact; in particular the possibility that entropy bounds should be defined in terms of volumes of regions rather than areas of surfaces.

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Ali Masoumi, Samir D. Mathur. 2015-01-24. A violation of the covariant entropy bound?. https://doi.org/10.1103/physrevd.91.084058

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