It is now known that when a massive star collapses under the force of its own gravity, the
final fate of such a continual gravitational collapse will be either a black hole or a naked …

Rapidly rotating Kerr black holes can accelerate particles to arbitrarily high energy if the
angular momentum of the particle is fine-tuned to some critical value. This phenomenon is …

Jacobson and Sotiriou showed that rotating black holes could be spun up past the extremal
limit by the capture of nonspinning test bodies, if one neglects radiative and self-force …

It has recently been pointed out that particles falling freely from rest at infinity outside a Kerr
black hole can in principle collide with an arbitrarily high center of mass energy in the …

We study the collision of particles in the vicinity of a horizon of a weakly magnetized
nonrotating black hole. In the presence of the magnetic field innermost stable circular orbits …

Recently, in the series of works a new effect of acceleration of particles by black holes has
been found. Under certain conditions, the energy in the center-of-mass system can become …

We argue that the possibility of having infinite energy in the center-of-mass frame of colliding
particles is a generic property of rotating black holes. We suggest a general model …

It has recently been pointed out that the spinning Kerr black hole with maximal spin could act
as a particle collider with arbitrarily high center-of-mass energy. In this paper, we will extend …

We derive a general formula for the center-of-mass (CM) energy for the near-horizon
collision of two particles of the same rest mass on the equatorial plane around a Kerr black …

We revisit here a previous argument due to Wald showing the impossibility of turning an
extremal<? format?> Kerr-Newman black hole into a naked singularity by plunging test …