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arXiv · 2609.10332

Generalized Black holes with Fully Non-aligned Electromagnetic Fields

Abstract

We develop a Pleba\'nski--Demia\'nski-adapted parametrization of the general Ovcharenko--Podolsk\'y solution and construct new families of generalized black holes in four-dimensional Einstein--Maxwell theory. These Petrov type~D spacetimes possess non-null, fully non-aligned electromagnetic fields. A restriction imposed in the previous parametrization is not required by the field equations in shifted coordinates. Removing it retains an independent charge parameter $q$, which may be real or purely imaginary. For $q^2\geq0$, both the metric and electromagnetic field admit a smooth aligned limit to the charged Pleba\'nski--Demia\'nski solution with $\Lambda=0$ and $e^2+g^2=q^2$. We impose angular conditions in the Griffiths--Podolsk\'y form allowing Killing horizon cross sections with spherical topology. The resulting eight-parameter class extends the seven-parameter class of Ovcharenko and Podolsk\'y [arXiv:2508.04850]. The remaining normalization condition is generically quartic, defining four algebraic branches. We give explicit metrics and electromagnetic fields for the non-twisting and $l=0$ twisting families and analyze their black hole and acceleration horizons, extremality, conicity, and further limits. We determine the effective-NUT-free branches of the latter family and their degenerate cases. Using the genuine Griffiths--Podolsk\'y form, we establish an explicit correspondence between the non-accelerating effective-NUT-free subclass and the Kerr--Newman--Bertotti--Robinson family and express its electromagnetic flux charges in our parameters. The $q^2<0$ sector includes the genuine uncharged Kerr--Bertotti--Robinson solution recently identified by Ovcharenko and Podolsk\'y [arXiv:2608.21672].

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BibTeXRIS

Hideo Furugori, Shinya Tomizawa. 2026-09-09. Generalized Black holes with Fully Non-aligned Electromagnetic Fields. https://arxiv.org/abs/2609.10332

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