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arXiv · 2109.00495

Retrolensing by light rays slightly inside and outside of a photon sphere around a Reissner-Nordström naked singularity

Naoki Tsukamoto
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Abstract

We investigate retrolensing of sunlights reflected by a photon sphere and by a potential barrier near an antiphoton sphere around a Reissner-Nordström naked singularity. We apply the deflection angles of light rays in strong deflection limits to the retrolensing. We show that the retrolensing by the photon sphere around the Reissner-Nordström naked singularity can be brighter than the one around a Reissner-Nordström black hole because of the existence of the rays which reflected by the potential barrier.

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Naoki Tsukamoto. 2021-12-21. Retrolensing by light rays slightly inside and outside of a photon sphere around a Reissner-Nordström naked singularity. https://doi.org/10.1103/physrevd.105.024009

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