Related papers: Higher Order Terms of Kerr Parameter for Blandford…
Scattering of particles in the gravitational field of Kerr black holes is considered. It is shown that scattering energy of particles in the centre of mass system can obtain very large values not only for extremal black holes but also for…
In this research, we explore the electromagnetic energy emitted by astrophysical black holes within the Kerr+PFDM spacetime, a model encompassing rotating black holes surrounded by dark matter. Our investigation focuses on black holes…
Black hole (BH) mergers are natural sources of gravitational waves (GWs) and are possibly associated with electromagnetic events. Such events from a charged rotating BH with an accretion on to it could be more energetic and…
Much of the success of gravitational-wave astronomy rests on perturbation theory. Historically, perturbative analysis of gravitational-wave sources has largely focused on post-Newtonian theory. However, strong-field perturbation theory is…
We investigate the energy extraction by the Penrose process in Kerr-MOG black hole~(BH). We derive the gain in energy for Kerr-MOG as \begin{eqnarray} \Delta {\cal E} \leq…
We investigate superradiant scattering off a rotating regular black hole described by a black-bounce metric which generalizes the Kerr spacetime of mass $M$ and specific angular momentum $a$ through a regularization parameter $p$ and two…
Typical mechanisms to extract energies from a rotating black hole are the Blandford-Znajek process and the Penrose process. The Penrose process requires a special condition that is difficult to occur in common astrophysical situations.…
Using a recursive solution of the Einstein equations, we consider the perturbative expansion of the metric corresponding to a Kerr black hole. Because the metric is a function of two parameters, Newton's constant G and the Kerr spin…
Employing higher order perturbation theory, we find a new class of charged rotating black hole solutions of Einstein-Maxwell-dilaton theory with general dilaton coupling constant. Starting from the Myers-Perry solutions, we use the electric…
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…
In this paper, we study the magnetic reconnection process of energy extraction from a rapidly rotating Kerr-Newman-modified-gravity (MOG) black hole by investigating the combined effect of black hole charge and the MOG parameter. We explore…
An analytical metric of four-dimensional General Relativity, representing an array of collinear and accelerating black holes, is constructed with the inverse scattering method. The solution can be completely regularised from any conical…
Sorce and Wald proposed a new version of gedanken experiments to examine the weak cosmic censorship conjecture (WCCC) in Kerr-Newmann black holes. However, their discussion only includes the second-order approximation of perturbation and…
From the Reissner-Nordstrom metric we obtain the higher-order terms for the deflection of light around a massive-charged black hole using the Lindstedt-Poincar\'e method to solve the equation of motion of a photon around the compact object.…
In previous work [1] we proposed an improvement of the WKB-based semianalytic technique of Iyer and Will for calculation of the quasiormal modes of black holes by constructing the Pad\'e approximants of the formal series for $\omega^{2}.$…
Extracting the rotational energy from a Kerr black hole (BH) is one of the crucial topics in relativistic astrophysics. Here, we give special attention to the Penrose ballistic process based on the fission of a massive particle $\mu_0$ into…
We discuss one of the possible origins of large-scale magnetic fields based on a continuous distribution of toroidal electric current flowing in the inner region of the disc around a Kerr black hole (BH) in the framework of general…
We study black hole solutions at first order in the Hartle-Thorne slow-rotation approximation in Horndeski gravity theories. We derive the equations of motion including also cases where the scalar depends linearly on time. In the…
According to Blandford & Znajek (1977), energy can be extracted electromagnetically from a rotating black hole, should the latter be endowed with a magnetic field supported by electric currents in a surrounding disk. We show that exact…
A number of long-standing puzzles, such as the origin of ultrahigh-energy cosmic rays, could perhaps be solved if we found a mechanism for effectively transferring energy from black holes to particles and, correspondingly, accelerating the…