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arXiv · 2110.03547

Can we detect a supertranslated black hole?

Subhodeep Sarkar·Shailesh Kumar·Srijit Bhattacharjee
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Abstract

We attempt to address the question of whether standard tests of general relativity can detect the presence of a black hole carrying a supertranslation field. In this regard, we study the photon sphere of a dynamical black hole carrying a supertranslation hair. We find that the dynamics of the photon sphere is quite subtle and it may offer an opportunity to differentiate a supertranslated black hole from its bald counterpart. This represents a first step towards understanding the observational signatures of a supertranslated dynamical black hole.

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Subhodeep Sarkar, Shailesh Kumar, Srijit Bhattacharjee. 2021-10-07. Can we detect a supertranslated black hole?. https://doi.org/10.1103/physrevd.105.084001

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