English

Black holes without boundaries

General Relativity and Quantum Cosmology 2009-03-20 v1

Abstract

We discuss some of the drawbacks of using event horizons to define black holes and suggest ways in which black holes can be described without event horizons, using trapping horizons. We show that these trapping horizons give rise to thermodynamic behavior and possibly Hawking radiation too. This raises the issue of whether the event horizon or the trapping horizon should be seen as the true boundary of a black hole. This difference is important if we believe that quantum gravity will resolve the central singularity of the black hole and clarifies several of the issues associated with black hole thermodynamics and information loss.

Keywords

Cite

@article{arxiv.0809.1711,
  title  = {Black holes without boundaries},
  author = {Alex B. Nielsen},
  journal= {arXiv preprint arXiv:0809.1711},
  year   = {2009}
}

Comments

8 pages. Invited essay for special edition of the International Journal of Modern Physics D

R2 v1 2026-06-21T11:18:39.754Z