Related papers: Intrinsic electromagnetic variability in celestial…
We propose a new electromagnetic-emission mechanism in magnetized, force-free plasma, which is driven by the evolution of the underlying dynamic spacetime. In particular, the emission power and angular distribution of the emitted…
Dynamics of charged particles in the vicinity of a rotating black hole embedded in the external large-scale magnetic field is numerically investigated. In particular, we consider a non-axisymmetric model in which the asymptotically uniform…
The Blandford-Znajek (BZ) mechanism is widely recognised as the most compelling process to extract rotational energy from an accreting black hole and power the emission of relativistic jets. We explore the universality of this process for…
We investigate the dynamics of charged and neutral particles in the vicinity of a Schwarzschild-like black hole immersed in an external magnetic field. We find that the innermost stable circular orbits (ISCOs) for charged particles are…
We study the effects of large scale magnetic fields on the dynamics of charged particles near a rotating black hole. We consider a scenario in which the initially neutral particles on geodesic orbits in the equatorial plane become ionized,…
General relativistic magnetohydrodynamic (GRMHD) simulations of accretion disks and jets associated with supermassive black holes show variability on a wide range of timescales. On timescales comparable to or longer than the gravitational…
We consider the Blandford-Znajek process of electromagnetic extraction of energy from a general axially symmetric asymptotically flat slowly rotating black hole. Using the general parametrization of the black-hole spacetime we construct…
We present the first alternative mechanisms to trigger black hole bomb phenomena beyond the famous superradiant instability. By incorporating nonlinear self-interaction into the massive charged scalar field in general relativity, we…
Previous realizations of synthetic gauge fields for ultracold atoms do not allow the spatial profile of the field to evolve freely. We propose a scheme which overcomes this restriction by using the light in a multimode cavity, in…
We use a numerical code to consider the nonlinear processes arising when a Reissner-Nordstrom black hole is irradiated by an exotic scalar field (modelled as a free massless scalar field with an opposite sign for its energy-momentum…
When approaching extremality, rotating black holes tend to expel the magnetic field in which they are immersed. This phenomenon, being reminiscent of the Meissner-Ochsenfeld effect in superconductors, is known as the black hole Meissner…
As a complementary or companion process to the Blandford-Znajek mechanism for the rotational energy extraction from a Kerr black hole to serve as a viable model for the central engine of quasar, AGN and even GRB, the magnetic alignment…
Black holes possess trapping regions which lead to intriguing dynamical effects. By properly scattering test fields off a black hole, one can extract energy from it, leading to the growth of the amplitude of the test field in expense of the…
Cosmic black holes can act as agents of particle acceleration. We study properties of a system consisting of a rotating black hole immersed in a large-scale organized magnetic field. Electrically charged particles in the immediate…
One of the major open questions related to the production of jets by accreting black holes is: why do sources with similar accretion powers produce so vastly different jet powers? What conditions are required to make a powerful jet? If jets…
Blazars show variability on timescales ranging from minutes to years, the former being comparable to and in some cases even shorter than the light-crossing time of the central black hole. The observed gamma-ray lightcurves can be described…
Many quasars and active galactic nuclei (AGN) appear in radio, optical, and X-ray maps, as a bright nuclear sources from which emerge single or double long, thin jets (Thomson et al., 1993). When observed with high angular resolution these…
Rotating black holes are known to launch relativistic jets and accelerate particles provided they accrete a magnetized plasma. However, it remains unclear how the global magnetic field orientation affects the jet powering efficiency. Here,…
We investigate how magnetic field variations around accreting black holes on event horizon scales affect the morphology of magnetically-driven jet on larger scales. By performing radiative transfer calculations on general relativistic…
We explore the connection between black hole spin and AGN power by addressing the consequences underlying the assumption in the recent literature that the gap region between accretion disks and black holes is fundamental in producing…