English

Bekenstein-Hawking entropy in expanding universes from black hole theorems

High Energy Physics - Theory 2014-05-29 v1 Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology

Abstract

We show that the use of suitable theorems for black hole formation in Friedmann expanding universes leads to a modification of the Bekenstein-Hawking entropy. By adopting an argument similar to the original Bekenstein one, we write down the expression for the Bekenstein-Hawking entropy suitable for non-static isotropic expanding universes together with the equation of state of a black hole. This equation can be put in a form similar to the one of an ideal gas but with a factor depending on the Hubble radius. Moreover, we give some argument on a possible relation between our entropy expression and the Cardy-Verlinde one. Finally, we explore the possibility that primordial inflation is due to black hole evaporation in our context.

Keywords

Cite

@article{arxiv.1405.6816,
  title  = {Bekenstein-Hawking entropy in expanding universes from black hole theorems},
  author = {Stefano Viaggiu},
  journal= {arXiv preprint arXiv:1405.6816},
  year   = {2014}
}

Comments

Accepted for publication in Mod. Phys. Lett A Vol. 29, Issue 17 (2014)