Related papers: A Black Hole inside Dark Matter and the Rotation C…
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…
The recently formulated model of black holes coupled to the radial flows of dark matter (RDM-stars) is considered and the shape of the galactic rotation curves predicted by the model is evaluated. Under the assumption that the density of…
We study the effective theory of slowly rotating black holes at the infinite limit of the spacetime dimension D. This large D effective theory is obtained by integrating the Einstein equation with respect to the radial direction. The…
Among various strong-curvature extensions to General Relativity, Einstein-Dilaton-Gauss-Bonnet gravity stands out as the only nontrivial theory containing quadratic curvature corrections while being free from the Ostrogradsky instability to…
We discuss a sufficiently large 4-dimensional Schwarzschild black hole which is in equilibrium with a heat bath. In other words, we consider a black hole which has grown up from a small one in the heat bath adiabatically. We express the…
A class of exact solutions are presented for the interior of black holes of solar mass and beyond. In a core enclosed by the inner horizon, the binding energy released by dissolution of the pre-collapse nuclei is stored in electrostatic and…
The observation of flat rotation curves in asymptotic region of galaxies implies that the dark matter density profile decreases exponentially with the gravitational potential in this region. It is curious that this behavior is identical to…
The evaluation of the energy-momentum distribution for a new four-dimensional, spherically symmetric, static and charged black hole spacetime geometry with constant non-zero topological Euler density is performed by using the…
We discuss a recently proposed limiting curvature theory of gravity and its application to the problem of singularities inside black holes. In this theory the growth of the curvature is suppressed by specially chosen inequality constraints…
Uniqueness problem of static axially symmetric black hole in magnetic Universe filled with {\it dark matter} component has been considered. The {\it dark matter} model comprises the additional $U(1)$-gauge field ({\it dark photon})…
Matter loses its original characteristics after entering a black hole, thus becoming a new kind of (black hole) matter. The property of this new matter cannot be measured experimentally, but some of it can be deduced theoretically from the…
We study a class of analytic models for a dark matter halo surrounding a Schwarzschild black hole sitting at the center of a galaxy, with a variable inner radius $r_{\text{in}}$ at which the density profile of the dark matter halo vanishes.…
In this report the exact rotating charged black hole solution to the Einstein--nonlinear electrodynamics theory with a cosmological constant is presented. This black hole is equipped with mass, rotation parameter, electric and magnetic…
The behavior of the angular velocity of a test particle moving in a stable circular orbit in the vacuum on the brane is considered. In the brane world scenario, the four dimensional effective Einstein equation acquire extra terms, called…
Einstein-Maxwell-Gauss-Bonnet-axion theory in $4$-dimensional spacetime is investigated in this paper through a "Kaluza-Klein-like" process. Dual to systems at finite temperature with background magnetic field on three dimensions, the…
Massive gravity previously constructed as the spin-2 quantum gauge theory leads in the mass zero limit to a modification of general relativity. As a relic from the massive theory a vector field v survives which couples to the metric only.…
A new version of the geometry inside a black hole is proposed, on the grounds of an idea given by Doran et al. The spacetime is still time dependent and is a solution of Einstein's equations with a stress tensor corresponding to an…
Under certain conditions imposed on the energy-momentum tensor, a theorem that characterizes a two-parameter family of static and spherically symmetric solutions to Einstein's field equations (black holes), is proved. A discussion on the…
With a prescribed Coulomb-type energy-momentum tensor, an exact solution of the Einstein field equations over a nonsimply-connected manifold is presented. This spherically symmetric solution has neither curvature singularities nor closed…
Electrically charged solutions for gravity with a conformally coupled scalar field are found in four dimensions in the presence of a cosmological constant. If a quartic self-interaction term for the scalar field is considered, there is a…