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arXiv · 2502.01759

Spinning generalizations of Majumdar-Papapetrou multi-black hole spacetimes: light rings, lensing and shadows

Zeus S. Moreira·Carlos A. R. Herdeiro·Luís C. B. Crispino
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Abstract

A generalization of the Majumdar-Papapetrou multi-black hole spacetime was recently constructed by Teo and Wan [1], describing charged and spinning (extremal) balanced black holes in asymptotically flat spacetime. We explore the dynamics of null geodesics on this geometry, focusing on the two-center solution. Using the topological charge formalism, we show that various light ring arrangements arise from different choices of individual angular momenta: light rings with opposite topological charges can merge and annihilate each other, resulting in configurations with a total of 4, 6, or 8 light rings. Using backward ray-tracing, we obtained the shadow and lensing of these spacetimes. The former, in particular, closely resembles those for the double-Kerr metric.

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Zeus S. Moreira, Carlos A. R. Herdeiro, Luís C. B. Crispino. 2025-02-03. Spinning generalizations of Majumdar-Papapetrou multi-black hole spacetimes: light rings, lensing and shadows. https://arxiv.org/abs/2502.01759

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