English

Gravitational entropy and thermodynamics away from the horizon

High Energy Physics - Theory 2015-06-03 v2 General Relativity and Quantum Cosmology

Abstract

We define, by an integral of geometric quantities over a spherical shell of arbitrary radius, an invariant gravitational entropy. This definition relies on defining a gravitational energy and pressure, and it reduces at the horizon of both black branes and black holes to Wald's Noether charge entropy. We support the thermodynamic interpretation of the proposed entropy by showing that, for some cases, the field theory duals of the entropy, energy and pressure are the same as the corresponding quantities in the field theory. In this context, the Einstein equations are equivalent to the field theory thermodynamic relation TdS=dE+PdV supplemented by an equation of state.

Keywords

Cite

@article{arxiv.1201.5754,
  title  = {Gravitational entropy and thermodynamics away from the horizon},
  author = {Ram Brustein and A. J. M. Medved},
  journal= {arXiv preprint arXiv:1201.5754},
  year   = {2015}
}

Comments

13 pages, Substantial changes to presentation. Conclusions unchanged, version to be published in PLB