English

Can a radiation gauge be horizon-locking?

General Relativity and Quantum Cosmology 2024-07-10 v2

Abstract

In this short Note, I answer the titular question: Yes, a radiation gauge can be horizon-locking. Radiation gauges are very common in black hole perturbation theory. It's also very convenient if a gauge choice is horizon-locking, i.e. the location of the horizon is not moved by a linear metric perturbation. Therefore it is doubly convenient that a radiation gauge can be horizon-locking, when some simple criteria are satisfied. Though the calculation is straightforward, it seemed useful enough to warrant writing this Note. Finally I show an example: the \ell vector of the Hartle-Hawking tetrad in Kerr satisfies all the conditions for ingoing radiation gauge to keep the future horizon fixed.

Cite

@article{arxiv.2404.10113,
  title  = {Can a radiation gauge be horizon-locking?},
  author = {Leo C. Stein},
  journal= {arXiv preprint arXiv:2404.10113},
  year   = {2024}
}

Comments

5+1 pages, comments welcome. v2: Matches version published to CQG

R2 v1 2026-06-28T15:55:07.365Z