English

Is gravitational entropy quantized ?

General Relativity and Quantum Cosmology 2009-02-23 v1 Astrophysics High Energy Physics - Theory

Abstract

In Einstein's gravity, the entropy of horizons is proportional to their area. Several arguments given in the literature suggest that, in this context, both area and entropy should be quantized with an equally spaced spectrum for large quantum numbers. But in more general theories (like, for e.g, in the black hole solutions of Gauss-Bonnet or Lanczos-Lovelock gravity) the horizon entropy is \emph{not} proportional to area and the question arises as to which of the two (if at all) will have this property. We give a general argument that in all Lanczos-Lovelock theories of gravity, it is the \emph{entropy} that has equally spaced spectrum. In the case of Gauss-Bonnet gravity, we use the asymptotic form of quasi normal mode frequencies to explicitly demonstrate this result. Hence, the concept of a quantum of area in Einstein Hilbert (EH) gravity needs to be replaced by a concept of \emph{quantum of entropy} in a more general context.

Keywords

Cite

@article{arxiv.0807.1481,
  title  = {Is gravitational entropy quantized ?},
  author = {Dawood Kothawala and T. Padmanabhan and Sudipta Sarkar},
  journal= {arXiv preprint arXiv:0807.1481},
  year   = {2009}
}

Comments

RevTeX 4; 4 pages; no figures

R2 v1 2026-06-21T10:58:57.623Z