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arXiv · 2107.07370

Light rings of stationary spacetimes

Rajes Ghosh·Sudipta Sarkar
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Abstract

We present a novel theorem regarding light rings in a stationary spacetime with an ergoregion. We prove that any stationary, axisymmetric, and asymptotically flat spacetime in 1 + 3 dimensions with an ergoregion must have at least one light ring outside the ergoregion. A possible extension of the proof for asymptotically de-Sitter and anti-de-Sitter spherically symmetric black holes is also discussed.

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Rajes Ghosh, Sudipta Sarkar. 2021-07-15. Light rings of stationary spacetimes. https://doi.org/10.1103/physrevd.104.044019

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