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arXiv · 2511.21538

Hidden symmetries and separability structures of Ovcharenko-Podolsk\'y and conformal-to-Carter spacetimes

Finnian Gray·David Kubiznak·Hryhorii Ovcharenko·Jiri Podolsky
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Abstract

Recently, a remarkable new class of spacetimes describing black holes immersed in a non-aligned electromagnetic field has been found. While still of type D, this class goes beyond the famous Pleba\'nski--Demia\'nski family. Here we demonstrate that the whole class admits a hidden symmetry encoded in the non-degenerate conformal Killing--Yano 2-form. Interestingly, as a direct consequence of non-alignment of the electromagnetic field and contrary to the Pleba\'nski--Demia\'nski class (where the field is aligned), such a symmetry no longer generates the full "tower of symmetries". Despite this, it enables one to separate variables in massless Hamilton--Jacobi, conformal wave, and massless Dirac equations, as well as allows one to tackle massless vector and tensor perturbations. These results provide a useful mathematical tool for discussing numerous (astrophysical) applications to be described by these metrics. Moreover, as we shall show, the novel spacetimes provide an interesting test-ground for studying the recently defined Penrose charges whose existence is intrinsically related to hidden rather than explicit symmetries.

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Finnian Gray, David Kubiznak, Hryhorii Ovcharenko, Jiri Podolsky. 2025-11-26. Hidden symmetries and separability structures of Ovcharenko-Podolsk\'y and conformal-to-Carter spacetimes. https://arxiv.org/abs/2511.21538

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