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arXiv · hep-th/9902088

Holography, Cosmology and the Second Law of Thermodynamics

Richard Easther·David A. Lowe
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Abstract

We propose that in time dependent backgrounds the holographic principle should be replaced by the generalized second law of thermodynamics. For isotropic open and flat universes with a fixed equation of state, the generalized second law agrees with the cosmological holographic principle proposed by Fischler and Susskind. However, in more complicated spacetimes the two proposals disagree. A modified form of the holographic bound that applies to a post-inflationary universe follows from the generalized second law. However, in a spatially closed universe, or inside a black hole event horizon, there is no simple relationship that connects the area of a region to the maximum entropy it can contain.

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Richard Easther, David A. Lowe. 1999-02-18. Holography, Cosmology and the Second Law of Thermodynamics. https://doi.org/10.1103/physrevlett.82.4967

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