相关论文: Super-Penrose process for nonextremal black holes

Due to the failure of thermodynamics for low temperature near-extremal black holes, it has long been conjectured that a "thermodynamic mass gap" exists between an extremal black hole and the lightest near-extremal state. For…

As with any black hole, asymptotically anti-de Sitter Kerr black holes are described by a small number of parameters, including a "mass parameter" $M$ that reduces to the AdS-Schwarzschild mass in the limit of vanishing angular momentum. In…

The center-of-mass energy of two particles can become arbitrarily large if they collide near the event horizon of an extremal Kerr black hole, which is called the Ba$\rm \tilde n$ados-Silk-West (BSW) effect. We consider such a high-energy…

We set to weigh the black holes at their event horizons in various spacetimes and obtain masses which are substantially higher than their asymptotic values. In each case, the horizon mass of a Schwarzschild, Reissner-Nordstr{\"o}m, or Kerr…

A universal geometric inequality for bodies relating energy, size, angular momentum, and charge is naturally implied by Bekenstein's entropy bounds. We establish versions of this inequality for axisymmetric bodies satisfying appropriate…

The properties of the ergosphere and energy extraction by Penrose process in a rotating non-Kerr black hole are investigated. It is shown that the ergosphere is sensitive to the deformation parameter $\epsilon$ and the shape of the…

When Hawking radiation from a rotating or non-rotating black hole becomes sufficiently intense, its own stress energy can no longer be treated as a perturbation on a fixed background. In this regime the outgoing flux may generate an…

Two particles can collide in the vicinity of a rotating black hole producing the divergent energy in the centre of mass frame (the BSW effect). However, it was shown recently that an observer at infinity can register quite modest energies E…

Recently it has been shown that the third law of black hole mechanics can be violated: an exactly extremal Reissner-Nordstrom black hole can form in finite time in gravitational collapse of matter with a large charge to mass ratio. However,…

We consider the Penrose process near the naked singularity in the Reissner-Nordstr\"{o}m metric. Particle 0 falls from infinity and decays to two fragments at some point $r_{0}$. We show that the energy extraction due to this process can be…

We investigate the electric Penrose process in Ay\'{o}n-Beato-Garc\'{i}a (ABG) black holes, both in the presence and absence of a cosmological constant, presenting the first such analysis within the context of regular black holes. Our study…

We consider circular particle motion under the action of an unspecified force in a static spherically symmetric spacetime. We derive the machinery that allows one to find the force acting on a circular particle and deduce whether its…

We study collisions of many point-like particles in three-dimensional anti-de Sitter space, generalizing the known result with two particles. We show how to construct exact solutions corresponding to the formation of either a black hole or…

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…

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 the result to the charged spinning black hole,…

When two particles collide near a black hole, the energy in their center of mass frame can, under certain conditions, grow unbounded. This is the Banados-Silk-West effect. We show that this effect retains its validity even if some force…

We investigate the possibility of arbitrarily high energy in the center of mass(CM) frame of colliding particles in the vicinity of the infinite red-shift surface of the spherically symmetric, static charged regular black holes (Bardeen…

We examine particle production from spherical bodies collapsing into extremal Reissner-Nordstr\"om black holes. Kruskal coordinates become ill-defined in the extremal case, but we are able to find a simple generalization of them that is…

We find a class of d=4, N=2 supergravity with $R^2$-interactions that admits exact BPS black holes. The prepotential contains quadratic, cubic and chiral curvature-squared terms. Black hole geometry realizes stretched horizon, and consists…

Superradiance, the phenomenon enabling energy extraction through radiation amplification, is not universal to all black holes. We show that semi-classical backreaction can induce superradiance, even when absent at the classical level.…