Related papers: Binary Black Hole in a Double Magnetic Monopole Fi…
The detection of gravitational waves from binary black holes sources has opened the possibility to search for electric charges and "dark" charges on black holes, the latter being candidates for dark matter. This requires theoretical…
We generalize duality invariance for the free Maxwell action in an arbitrary background geometry to include the presence of electric and magnetic charges. In particular, it follows that the actions of equally charged electric and magnetic…
The interaction of black holes with ambient magnetic fields is important for a variety of highly energetic astrophysical phenomena. We study this interaction within the force-free approximation in which a tenuous plasma is assumed to have…
Gravitational waves from merging binary black holes present exciting opportunities for understanding fundamental aspects of gravity, including nonlinearities in the strong-field regime. One challenge in studying and interpreting the…
We review the main physical processes that lead to the formation of stellar binary black holes (BBHs) and to their merger. BBHs can form from the isolated evolution of massive binary stars. The physics of core-collapse supernovae and the…
An intriguing open problem in general relativity is whether a stationary equilibrium configuration of multiple, physically relevant black holes can exist. In such a hypothetical setup, the gravitational attraction would need to be balanced…
It is an interesting open problem whether two non-extremal rotating and electrically charged black holes can be in physical equilibrium, which might be possible due to a balance between the gravitational attraction and the spin-spin and…
We present an exact black hole solution in a model having besides gravity a dilaton and a monopole field, which is a generalization of a black hole solution we have found. The new solution, as the previous one, has three free parameters,…
Black holes are the simplest macroscopic objects, and provide unique tests of General Relativity. They have been compared to the Hydrogen atom in quantum mechanics. Here, we establish a few facts about the simplest systems bound by gravity:…
In this paper we analyze a binary system consisting of a star and a rotating black hole. The electromagnetic radiation emitted by the star interacts with the background of the black hole and stimulates the production of dilaton waves. We…
Using a generalized Weyl formalism, we show how stationary, axisymmetric solutions of the four-dimensional vacuum Einstein equation can be turned into static, axisymmetric solutions of five-dimensional dilaton gravity coupled to a two-form…
We examine the angular momentum of an electric charge e placed at rest outside a dilaton black hole with magnetic charge Q. The electromagnetic angular momentum which is stored in the electromagnetic field outside the black hole shows…
As a black hole and neutron star approach during inspiral, the field lines of a magnetized neutron star eventually thread the black hole event horizon and a short-lived electromagnetic circuit is established. The black hole acts as a…
The electric and magnetic black hole solutions are found by coupling the recently introduced nonlinear electrodynamics (NED) model, called "double logharitmic nonlinear electrodynamics" with cosmological Einstein gravity. The solutions…
We reconsider the problem of the formation of a large-scale magnetic field in the accretion disks around black holes. In contrast with previous work we take into account the nonuniform vertical structure of the disk. The high electrical…
We show that the attractor mechanism for generic black hole is a consequence of the double-horizon. Investigation of equations of motion shows that in the case of the double-horizon black holes, the dynamics of the geometry, the scalars and…
Magnetic layers are narrow regions where the field direction changes sharply. They often occur in the association with neutral points of the magnetic field. We show that an organised field can produce these structures near a rotating black…
Stellar-mass binary black hole (BBH) mergers occurring within the disks of active galactic nuclei (AGN) are promising sources for gravitational waves detectable by the LIGO, Virgo, and KAGRA (LVK) interferometers. Some of these events have…
We construct a new extreme black hole solution in toroidally compactified heterotic string theory. The black hole saturates the Bogomol'nyi bound, has zero angular momentum, but nonzero electric dipole moment. It is obtained by starting…
We show that under certain astrophysical conditions a binary system consisting of two compact objects can be stabilized against indefinite shrinking of orbits due to the emission of gravitational radiation. In this case, the lighter binary…