Related papers: Five-dimensional Myers-Perry Black Holes as Partic…
In a paper posted on the arXiv a few weeks ago Berti, Brito and Cardoso \cite{Berti+14} suggest that ultra-high-energy particles can emerge from collisions in a black hole's ergosphere. This can happen if the process involves a particle on…
A critique of the singularity theorems of Penrose, Hawking, and Geroch is given. It is pointed out that a gravitationally collapsing black hole acts as an ultrahigh energy particle accelerator that can accelerate particles to energies…
We study collision of two general geodesic particles around the Kerr-Newman (KN) black hole and get the center-of-mass (CM) energy of the non-marginally and marginally bound critical particles in the direct collision and LSO collision…
We study high energy charged particle collisions near the horizon in an electromagnetic field around a rotating black hole and reveal the condition of the fine-tuning to obtain arbitrarily large center-of-mass (CM) energy. We demonstrate…
Recently, in the series of works a new effect of acceleration of particles by black holes was found. Under certain conditions, the energy in the centre of mass frame can become infinitely large. The essential ingredient of such effect is…
In low-scale gravity models, a particle collider with trans-Planckian collision energies can be an ideal place for producing black holes because a large amount of energy can be concentrated at the collision point, which can ultimately lead…
It is shown that in the Schwarzschild background there exists direct counterpart of the Ba\~{n}ados-Silk-West effect for spinning particles. This means that if two particles collide near the black hole horizon, their energy in the centre of…
Recently, a generalised solution for Einstein equations of a rotating compact body, surrounded by matter field was proposed, which is the Kerr-Newman spacetime with an anisotropic matter. The solution possesses an additional hair, along…
We numerically investigate the formation of D-dimensional black holes in high-energy particle collision with the impact parameter and evaluate the total cross section of the black hole production. We find that the formation of an apparent…
We study the possibility of obtaining unbound energy E_{c.m.} in the centre of mass frame when two particles collide near the inner black hole horizon. We consider two different cases - when both particles move (i) in the same direction or…
On the basis of the Kerr metric as a model for a spinning black hole accreting test particles from rest at infinity, I show that the center-of-mass energy for a pair of colliding particles is generically divergent at the inner horizon. This…
We study the collision of two particles with equal masses moving in the equatorial plane near horizon of the rotating regular Ay\'on-Beato-Garc\'ia (ABG) black hole (BH) and calculate the center-of-mass (CM) energy for the colliding…
We consider theories with gravity, gauge fields and scalars in four-dimensional asymptotically flat space-time. By studying the equations of motion directly we show that the attractor mechanism can work for non-supersymmetric extremal black…
In this paper we have studied particle collision around a spinning dilaton black hole in 2 +1 dimensions. This black hole is a solution to the low energy string theory in 2+1 dimensions. Time-like geodesics are presented in detail and the…
Geodesic completeness needs existence near the horizon of the black hole of "white hole" geodesics coming from the region inside of the horizon. Here we give the classification of all such geodesics with the energies $E/m \le 1$ for the…
It is shown that the energy in the centre of mass frame of two colliding particles in free fall at any point of the ergosphere of the rotating black hole can grow without limit for fixed energy values of particles on infinity. The effect…
We study collisions of boosted rotating black holes in $D=6$ and 7 spacetime dimensions with a non-zero impact parameter. We find that there exists an open set of initial conditions such that the intermediate state of the collision is a…
An introduction is given to a meeting on the role of massive and stellar black holes in powering non-thermal activity in a rich variety of cosmic sources. Relevant properties of magnetized, spinning black holes are summarized and their…
The critical behavior of Myers-Perry black holes with equal angular momenta in even dimensions are studied. We include the corrections beyond the semiclassical approximation on Hawking temperature in the grand canonical ensemble. Having…
We study collisions of massive pointlike particles in three dimensional anti-de Sitter space, generalizing the work on massless particles in [1]. We show how to construct exact solutions corresponding to the formation of either a black hole…