Related papers: Shock Wave Mixing in Einstein and Dilaton Gravity
Coalescing black-hole binaries are expected to be the strongest sources of gravitational waves for ground-based interferometers as well as the space-based interferometer LISA. Recent progress in numerical relativity now makes it possible to…
Gravitational waves deliver information in exquisite detail about astrophysical phenomena, among them the collision of two black holes, a system completely invisible to the eyes of electromagnetic telescopes. Models that predict…
We have numerically investigated close scattering processes of two black holes (BHs). Our careful analysis shows for the first time a non-merging ringdown gravitational wave coming from dynamical tidal deformations of individual BHs during…
Numerical relativity has recently yielded a plethora of results about kicks from spinning mergers which has, in turn, vastly increased our knowledge about the spin interactions of black hole systems. In this work we use black hole…
Phonons in Bose-Einstein condensates propagate as massless scalar particles on top of an emergent acoustic metric. This hydrodynamics/gravity analogy can be exploited to realize acoustic black holes, featuring an event horizon that traps…
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…
Static spherically symmetric asymptotically flat solutions to the U(1) Born-Infeld theory coupled to gravity and to a dilaton are investigated. The dilaton enters in such a way that the theory is $SL(2,R)$- symmetric for a unit value of the…
The association of an electromagnetic signal with the merger of a pair of supermassive black holes would have many important implications. For example, it would provide new information about gas and magnetic field interactions in dynamical…
We consider the effects of gravitons in the collapse of baryonic matter that forms a black hole. We first note that the effective number of (soft off-shell) gravitons that account for the (negative) Newtonian potential energy generated by…
A relativistic quantum model of particle scattering near the horizon of a microscopic black hole unifies gravity and the harmonic-oscillator force. The model is obtained by modifying a harmonic-oscillator nonstandard Lagrangian for a closed…
In a strong electromagnetic field, gravitational waves are converted into electromagnetic waves of the same frequency, and vice versa. Here we calculate the scattering and conversion cross sections for a planar wave impinging upon a…
We numerically investigate the dynamics near black hole formation of solutions to the Einstein--Vlasov system in axisymmetry. Our results are obtained using a particle-in-cell and finite difference code based on the $(2+1)+1$ formulation of…
Understanding the predictions of general relativity for the dynamical interactions of two black holes has been a long-standing unsolved problem in theoretical physics. Black-hole mergers are monumental astrophysical events, releasing…
We extend the formulation for perturbations of maximally symmetric black holes in higher dimensions developed by the present authors in a previous paper (hep-th/0305147) to a charged black hole background whose horizon is described by an…
We consider Einstein-Maxwell-dilaton gravity with charged dust and interaction of the form $P(\chi) F_{\mu\nu} F^{\mu\nu}$, where $P(\chi)$ is an arbitrary function of the dilaton field $\chi$ that can be normal or phantom. For any regular…
We numerically investigate the interior of a four-dimensional, spherically symmetric charged black hole accreting neutral null fluid. Previous study by Marolf and Ori suggested that late infalling observers encounter an effective shock wave…
Being arguably the most massive binary black hole merger event observed to date, GW190521 deserves special attention. The exceptionally loud ringdown of this merger makes it an ideal candidate to search for gravitational wave echoes, a…
We discuss the two-dimensional dilaton gravity with a scalar field as the source matter where the coupling with the gravity is given, besides the minimal one, through an external field. This coupling generalizes the conformal anomaly in the…
It has recently been pointed out that, under certain conditions, the energy of particles accelerated by black holes in the center-of-mass frame can become arbitrarily high. In this paper, we study the collision of two particles in the case…
Gravitational waves are rapidly becoming a very reliable tool for testing alternative theories of gravity. In particular, features in the gravitational wave emission during black hole ringdown phase provide a direct probe of the spacetime…