Related papers: Is the Kerr black hole a super accelerator?
Arguments are given for the conclusion that the energy of collision of two ultrarelativistic elementary particles due to gravitational radiation cannot exceed the Planck value. Comparison of the gravitational and electromagnetic radiation…
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…
A new simple and general explanation of the effect of acceleration of particles by black holes to infinite energies in the centre of mass frame is suggested. It is based on kinematics of particles moving near the horizon. This effect arises…
Here we consider static, axially symmetric, rotating and charged Kerr-Sen Dilaton-Axion black hole metric in generalized Boyer-Lindquist coordinates as particle accelerators. We obtain the geodesic motions of particle. We find the effective…
A possible process to destroy a black hole consists on throwing point particles with sufficiently large angular momentum into the black hole. In the case of Kerr black holes, it was shown by Wald that particles with dangerously large…
We investigate particle collisions in non-extremal black hole that can probably induced to extremely high center of mass energy $E_{\text{cm}}$. We consider the collision of two particles where first particle comes from far to the outer…
A new mechanism for the acceleration of ultra high energy cosmic rays (UHECRs) is presented here. It is based on the tunnel-ionization of neutral atoms approaching electrically charged stellar black holes and on the repulsion of the…
It is known that the center-of-mass energy of the collision of two massive particles following geodesics around a black hole presents a maximum. The maximum energy increases when the black hole is endowed with spin, and for a maximally…
We investigate here the particle acceleration and high energy collision in the Kerr geometry containing a naked singularity. We show that the center of mass energy of collision between two particles, dropped in from a finite but arbitrarily…
If two particles collide near the black hole horizon, the energy in the centre of mass (CM) frame can grow indefinitely (the so-called the BSW effect). This requires fine-tuning the parameters (the energy, angular momentum or electric…
We explore the multi-black hole spacetimes from the perspective of the ultra-high energy particle collisions. Such a discussion is limited to the spacetimes containing a single black hole so far. We deal with the Majumdar-Papapetrou…
The origin of the ultra-high-energy particles we receive on the Earth from the outer space such as EeV cosmic rays and PeV neutrinos remains an enigma. All mechanisms known to us currently make use of electromagnetic interaction to…
We consider collision of two particles that move in the equatorial plane near a general stationary rotating axially symmetric extremal black hole. One of particles is critical (with fine-tuned parameters) and moves in the outward direction.…
It is well known that some black holes can act as accelerators for particles without spin. Recently, there are some works considering collision of two spinning particles in the background of Schwarzschild and Kerr black holes and it was…
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…
We derive an upper limit to the energy of nuclei accelerated via the Fermi mechanism in any relativistic shockwave, driven by any astrophysical engine. This bound is accessible to current and upcoming ultra-high energy neutrino experiments.…
We consider collisions of particles near generic axially symmetric extremal black holes. We examine possibility of indefinitely large extraction of energy (the so-called super-Penrose process) in the limit when the point of collision…
The aim of the paper is the consideration of particle collisions in the vicinity of the horizon of rotating black holes. Existence of geodesics for massive and massless particles arising from the region inside of the gravitational radius in…
We study properties of particles with zero or negative energy and a nonzero orbital angular momentum in the ergosphere of a rotating black hole. We show that the sign of the particle energy is uniquely determined by the angular velocity of…
The center-of-mass energy of two particles colliding near the horizon of a maximally rotating black hole can be arbitrarily high if the angular momentum of either of the incident particles is fine-tuned, which we call a critical particle.…