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arXiv · 2101.02019

Light from Reissner-Nordstrom-de Sitter black holes

Ion I. Cotaescu
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Abstract

We derive for the first time the form of the spiral null geodesics around the photon sphere of the Reissner-Nordstrom black hole in the de Sitter expanding universe. Moreover, we obtain the principal parameter we need for deriving, according to our method [I. I. Cot\u aescu. {Eur. Phys. J. C.} (2021) 81:32], the black hole shadow and the related redshift as measured by a remote observer situated in the asymptotic zone. We obtain thus a criterion of detecting charged black holes without peculiar velocities when one knows the mass, redshift and the black hole shadow.

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Ion I. Cotaescu. 2021-01-06. Light from Reissner-Nordstrom-de Sitter black holes. https://doi.org/10.1142/s0217732321501625

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