Related papers: Accelerating strangelets via Penrose process in no…
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 work we present a new view on the thermodynamics of black holes introducing effects of irreversibility by employing thermodynamic optimization and finite-time thermodynamics. These questions are of importance both in physics and in…
The Penrose process (PP) is an ingenious mechanism of extracting rotational energy from a rotating black hole, however it was soon realized that it was not very efficient for its astrophysical applications for powering the central engine of…
I present a theoretical and numerical (Monte Carlo) N-particle analysis of Penrose scattering processes in the ergosphere of a supermassive Kerr black hole. These GR model calculations reveal that the observed high energies and luminosities…
We discuss the possible imprints of Strange Quark Matter (SQM) in cosmic ray data. In particular, we investigate the propagation of SQM through the atmosphere and discuss: i) direct candidates for strangelets, ii) exotic events interpreted…
We have investigated the properties of the ergosphere and the energy extraction by Penrose process in a Konoplya-Zhidenko rotating non-Kerr black hole spacetime. We find that the ergosphere becomes thin and the maximum efficiency of energy…
We suggest that ultra-high-energy (UHE) cosmic rays (CRs) may be accelerated in ultra-relativistic flows via a one-shot mechanism, the "espresso" acceleration, in which already-energetic particles are generally boosted by a factor of…
In this paper, we study the electric Penrose energy extraction for charged particles in the spacetime of a covariant quantum-corrected Reissner-Nordstr\"om black hole. We first derive the equations of motion and effective potential for…
The Cauchy problem is considered for the scalar wave equation in the Kerr geometry. We prove that by choosing a suitable wave packet as initial data, one can extract energy from the black hole, thereby putting supperradiance, the wave…
Magnetic Penrose process (MPP) is not only the most exciting and fascinating process mining the rotational energy of black hole but it is also the favored astrophysically viable mechanism for high energy sources and phenomena. It operates…
We use a Monte Carlo code to calculate the geodesic orbits of test particles around Kerr black holes, generating a distribution function of both bound and unbound populations of dark matter particles. From this distribution function, we…
The environs of supermassive black holes are among the universe's most extreme phenomena. Understanding the physical processes occurring in the vicinity of black holes may provide the key to answer a number of fundamental astrophysical…
Ultra-high-energy cosmic rays (UHECRs) have been tried to be related to the most varied and powerful sources known in the universe. Gamma-ray bursts (GRBs) are natural candidates. Here, we argue that cosmic rays can be accelerated by large…
Strange quark matter (SQM) is considered a possible true ground state of QCD at high densities. This idea motivates research on exotic compact objects and certain cosmic-ray phenomena. For instance, the remnant HESS J1731-347 contains a…
The exact mechanism by which astrophysical jets are formed is still unknown. It is believed that necessary elements are a rotating (Kerr) black hole and a magnetised accreting plasma. We model the accreting plasma as a collection of…
The aim of the present article is to evaluate the motion of charged test particles in the vicinity of a near-extremal rotating black hole in the presence of magnetic fields. Euler-Lagrange motion equations and effective potential methods…
In this paper, we consider a well-established magnetic Penrose process (MPP) and bring out its impact on the efficiency of energy extraction from higher dimensional (i.e., $D>4$) black holes. We derive the field equations of motion and…
Particles or waves scattered from a rotating black hole can be amplified through the process of Penrose superradiance, though this cannot currently be observed in an astrophysical setting. However, analogue gravity studies can create…
Penrose process on rotational energy extraction of the black hole in the Kerr-Taub-NUT spacetime is studied. It has been shown that for the radial motion of particles NUT parameter slightly shifts the shape of the effective potential down.…
Astrophysical bounds on the properties and abundances of primordial quark nuggets and cosmic ray strangelets are reviewed. New experiments to search for cosmic ray strangelets in lunar soil and from the International Space Station are…