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arXiv · 2404.10113

Can a radiation gauge be horizon-locking?

Leo C. Stein
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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.

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Leo C. Stein. 2024-04-15. Can a radiation gauge be horizon-locking?. https://doi.org/10.1088/1361-6382%2Fad563b

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