Related papers: Mass-Angular Momentum Inequality For Black Ring Sp…
Chaotic motion near black holes has recently been examined through the lens of the Maldacena-Shenker-Stanford (MSS) chaos-bound, but reported violations remain contradictory. A significant source of ambiguity stems from treating the…
We rederive the relation between the specific angular momentum j_* and the mass M_* of the stellar matter in galaxies of different morphological types. This is a revision of the j_*--M_* diagram presented in our recent comprehensive study…
The deep connection between black hole thermodynamics and spacetime geometry remains a central focus of general relativity. While recent studies have revealed a precise correspondence for null orbits, given by $K = -\lambda^2$ between the…
We investigate the threshold of gravitational collapse with angular momentum, under the assumption that the critical solution is spherical and self-similar and has two growing modes, namely one spherical mode and one axial dipole mode…
We derive mass-independent equations and inequalities for Kerr-Newman-anti-de Sitter black holes. In particular, we obtain an equation that relates electric charge, angular momentum and the areas of the event and Cauchy horizons. An…
We investigate the energy distribution of a black hole in various spacetimes as reckoned by a distant observer using the quasi-local energy approach. In each case the horizon mass of a black hole: neutral, charged or rotating, is found to…
Bounds for the area of general closed marginally trapped surfaces (MTSs) are presented. They do not require any stability condition, and are determined by a constant that depends on a particular component of the Einstein tensor on the…
We study critical phenomena in the collapse of rotating ultrarelativistic perfect fluids, in which the pressure $P$ is related to the total energy density $\rho$ by $P=\kappa\rho$, with $\kappa$ a constant. We generalize earlier results for…
We provide evidence for a holographic duality between superconformal quantum mechanics on the moduli space of Yang-Mills instantons and M-theory in certain asymptotically $AdS_{7}\times S^{4}$ backgrounds with a plane-wave boundary metric.…
We study gravitational perturbations sourced by a rotating test shell collapsing into five-dimensional Myers-Perry black holes in anti-de Sitter (AdS). Our attention is restricted to the case in which the two possible angular momenta of the…
The black hole mass measurement in active galaxies is a challenge, particularly in sources where the reverberation method cannot be applied. We aim to determine the black hole mass in a very special object, RE J1034+396, one of the two AGN…
We discuss how in certain theories of spacetime admitting a maximal proper acceleration Hawking radiation does not completely evaporate the black hole. The black hole remnant's mass depends on the inverse of the maximal acceleration.…
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…
In this paper we consider a metric of a rotating black hole in conformal gravity. We calculate the thermodynamical quantities for this rotating black hole including Hawking temperature and entropy in four dimensional space-time, as we…
Several classes of conformally-flat and spherically symmetric exact solutions to the Einstein field equations coupled with either a massless scalar field or a radiation fluid are given, and their main properties are studied. It is found…
Let $\Omega$ be a smooth, bounded subset of $\mathbb{R}^3$ diffeomorphic to a ball. Consider $M = \mathbb{R}^3 \setminus \Omega$ equipped with an asymptotically flat metric $g = f^4 g_{\text{euc}}$, where $f\to 1$ at infinity. Assume that…
We combine Hubble Space Telescope spectroscopy and ground-based integral-field data from the SAURON and OASIS instruments to study the central black hole in the nearby elliptical galaxy NGC 3379. From these data, we obtain kinematics of…
We study the mass-charge relation for the semiclassical extremal black hole of the $S$-wave sector Einstein-Maxwell theory coupled to $N$ conformal scalars. The classical ratio $M/{|Q|}=1$ is shown to be modified to $M/{|Q|} \simeq 1-k/6$…
We propose a new parametric framework to describe in generic metric theories of gravity the spacetime of spherically symmetric and slowly rotating black holes. In contrast to similar approaches proposed so far, we do not use a Taylor…
It is well known that the three parameters that characterize the Kerr black hole (mass, angular momentum and horizon area) satisfy several important inequalities. Remarkably, some of these inequalities remain valid also for dynamical black…