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arXiv · 2608.21672

Kerr-Newman and genuine Kerr black holes in the Bertotti-Robinson magnetic field

Hryhorii Ovcharenko·Jiri Podolsky
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Abstract

We present a spacetime that describes a rotating and charged black hole immersed in an external magnetic field. This exact solution to the Einstein-Maxwell equations has a surprisingly simple form which reduces to standard Kerr-Newman metric, and to the uniform Bertotti-Robinson magnetic universe. We show that the Kerr-BR solution presented in [Phys. Rev. Lett. {\bf 135}, 181401 (2025)] has a special charge, and we identify a genuine Kerr black hole without any charge, in the magnetic field. In the weak-field limit it gives the Wald solution. We analyze main physical properties of the new family, namely singularities, horizons, regularity of axes, charges, entropy and temperature.

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Hryhorii Ovcharenko, Jiri Podolsky. 2026-08-21. Kerr-Newman and genuine Kerr black holes in the Bertotti-Robinson magnetic field. https://arxiv.org/abs/2608.21672

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