Related papers: Electromagnetic fields around black holes and Meis…
The field equations of the original Kaluza's theory are analyzed and it is shown that they lead to modification of Einstein's equations. The appearing extra energy-momentum tensor is studied and an example is given where this extra…
We found quasinormal modes, both in time and frequency domains, of the Ernst black holes, that is neutral black holes immersed in an external magnetic field. The Ernst solution reduces to the Schwarzschild solution, when the magnetic field…
The three-dimensional static and circularly symmetric solution of the Einstein-Born-Infeld-dilaton system is derived. The solutions corresponding to low energy string theory are investigated in detail, which include black hole solutions if…
We study a rotating black hole with anisotropic matter and electromagnetic fields. We show that the electromagnetic field has the same form as the corresponding one in the Kerr-Newman geometry. The reason is thanks to the specific form of…
We discuss two dimensional string theories containing gauge fields introduced either via coupling to open strings, in which case we get a Born-Infeld type action, or via heterotic compactification. The solutions to the modified background…
In this paper, we investigate the effects of the {\ae}ther field and the electric charge on the observed shadow of two types of charged black holes in the Einstein-Maxwell-{\AE}ther theory. By considering that the Einstein-Maxwell-{\AE}ther…
In the present paper we study the long-standing problem for the thermodynamics of magnetized dilaton black holes. For this purpose we construct an exact solution describing a rotating charged dilaton black hole immersed in an external…
Radiation reaction acting on a charged particle moving at a stable circular orbit of a magnetized black hole can lead to the shift of the orbital radius outwards from the black hole. The effect causes increase of the energy and angular…
We examine the issue of magnetic charge quantization in the presence of black holes. It is pointed out that quantization of magnetic charge can lead to the mass quantization for magnetically charged black holes. We also discuss some…
Astrophysical black holes are often embedded into electromagnetic fields, that can usually be treated as test fields not influencing the spacetime geometry. Here we analyse the innermost stable circular orbit (ISCO) of charged particles…
Black hole solutions to the Einstein equations coupled with the Born--Infeld electromagnetism associated with generalized nonlinear electrodynamics, carrying both electric and magnetic charges, often referred to as dyonically charged black…
The free fall of electric charges and dipoles, radial and freely falling into the Schwarzschild black hole event horizon, was considered. Inverse effect of electromagnetic fields on the black hole is neglected. Dipole was considered as a…
Understanding the mechanisms of particle acceleration from the vicinity of black holes poses a challenge. Electromagnetic effects are thought to be a prime suspect, but details still need an explanation. To this end, we study a…
We consider the coupling of the electromagnetic field to a non-local gravity theory comprising of the Einstein-Hilbert action in addition to a non-local $R\, {\Box}^{-2} R$ term associated with a mass scale $m$. We demonstrate that in the…
We scrutinize properties of electrical charges bounded to visible and dark matter sectors, in the vicinity of a magnetic poles of both sectors. It turns out that the considered system has an angular momentum despite the charges are at rest.…
We investigate stationary models of magnetized, self-gravitating disks around black holes. The disks are assumed to rotate according to a recently introduced Keplerian rotation law. We consider different prescriptions of the toroidal…
We numerically construct a family of stationary, axisymmetric black hole solutions in Einstein-Born-Infeld theory, incorporating both electric charge and rotation. Our results indicate that when nonlinear electromagnetic effects are weak,…
The Standard Model of particle physics predicts the speed of light to be a universal speed of propagation of massless carriers. However, other possibilities exist -- including Lorentz-violating theories -- where different fundamental fields…
We consider classical solutions for strings ending on magnetically charged black holes in four-dimensional Kaluza-Klein theory. We examine the classical superstring and the global vortex, which can be viewed as a nonsingular model for the…
We investigate the scenario of black holes coupled with the Euler-Heisenberg nonlinear electromagnetic field in the framework of $f(R,T)$ gravity. The black hole solutions for electrically charged, magnetically charged and the dyonic case…