17 papers
Thermodynamics of Genuine Kerr-Bertotti-Robinson Black Holes
David Kubiznak, Hryhorii Ovcharenko, Jiri Podolsky
We propose a thermodynamic description of the genuine Kerr-Bertotti-Robinson (Kerr-BR) black hole spacetimes. Contrary to previous studies, such solutions no longer have electric c…
Kerr-Newman and genuine Kerr black holes in the Bertotti-Robinson magnetic field
Hryhorii Ovcharenko, Jiri Podolsky
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 surprisi…
Circular orbits in spherically symmetric spacetimes and BSW effect with nonzero force
Hryhorii Ovcharenko, O. B. Zaslavskii
We consider circular particle motion under the action of an unspecified force in a static spherically symmetric spacetime. We derive the machinery that allows one to find the force…
Comment on the "New Rotating Black Hole in Electromagnetic Fields: Cosmological Horizon without Cosmological Constant''
Hryhorii Ovcharenko
In this comment we discuss some properties of the novel spacetime, recently found in [L. Ma, H. Lü, arXiv:2606.23782]. In particular, we draw attention to the background of this s…
Uniqueness of stationary axisymmetric type D black holes with non-aligned electromagnetic field
Hryhorii Ovcharenko, Jiri Podolsky
We demonstrate the uniqueness of the spacetimes recently found by us in [H. Ovcharenko and J. Podolsky, Phys. Rev. D 112 (2025) 064076]. First, we prove that the conformal-to-Carte…
Exact Kerr-Newman-(A)dS and other spacetimes in bumblebee gravity: employing a simple generating technique
Hryhorii Ovcharenko
In this work, we show that if the bumblebee field in the Einstein-bumblebee theory is given by its vacuum expectation value () and it is not dynamical ($\partial_μB_ν-…