相关论文: Spherical accretion by normal and phantom Einstein…
We introduce a formulation of Eulerian general relativistic hydrodynamics which is applicable for (perfect) fluid data prescribed on either spacelike or null hypersurfaces. Simple explicit expressions for the characteristic speeds and…
(Abridged) We investigate non-spherical behavior of gas accreting onto a central supermassive black hole performing simulations using the SPH code GADGET-3 including radiative cooling and heating by the central X-ray source. As found in…
This investigation is devoted to the solutions of Einstein's field equations for a circularly symmetric anisotropic fluid, with kinematic self-similarity of the first kind, in $(2+1)$-dimensional spacetimes. In the case where the radial…
We have constructed a spherically symmetric structure model in a cosmological background filled with perfect fluid with non-vanishing pressure and studied its quasi-local characteristics. This is done by using the Lema\^{i}tre solution of…
We investigate the dynamical behavior of phantom energy near stringy magnetically charged black hole. For this purpose, we derive equations of motion for steady-state spherically symmetric flow of phantom energy onto the stringy…
Regular black hole solutions are found among the Guilfoyle exact solutions. These are spherically symmetric solutions of general relativity coupled to Maxwell's electromagnetism and charged matter where the metric potentials and…
We study black hole evaporation of near-extremal black holes in spherically reduced models with asymptotically Minkowskian spacetime, with the effects of the back-reaction on the geometry included semi-classically. The stress-energy tensor…
Null geodesics of normal and phantom Einstein-Maxwell-dilaton black holes are determined analytically by the Weierstrass elliptic functions. The black hole parameters other than the mass enter, with the appropriate signs, the formula for…
In the vicinity of black holes, the influence of strong gravity, plasma physics, and emission processes govern the behavior of the system. Since observations such as those carried out by the EHT are not yet able to unambiguously constrain…
We investigate the spherical accretion of various types of fluids onto a Schwarzschild-like black hole solution modified by a Kalb-Ramond field implementing spontaneous Lorentz symmetry violation (LV). The system is analyzed for isothermal…
In this paper, we investigate evaporation and accretion of uncharged, non-rotating, spherically symmetric black-holes from the path integral perspective. We show that the effective actions derived using the path integral techniques…
A number of `modified' Newtonian potentials of various forms are available in the literature which accurately approximate some general relativistic effects important for studying accretion discs around a Schwarzschild black hole. Such…
We study the corrections to the entropy of Einstein-Maxwell dilaton-axion black holes beyond semiclassical approximations. We consider the entropy of the black hole as a state variable and derive these corrections using the exactness…
We present an analytic solution for accretion of a gaseous medium with adiabatic equation of state onto a charged dilaton black hole which moves at a constant velocity. We determine the four-velocity of accreted flow and find that it…
Considering a generalised action for Einstein Maxwell theory in four dimensions coupled to scalar and pseudo-scalar fields, the thermodynamic properties of asymptotically flat black holes solutions in such a background are investigated.…
Results are presented from a time--dependent, numerical investigation of spherical accretion onto black holes, within the framework of relativistic radiation hydrodynamics. We have studied the stability of self--consistent, stationary…
Static spherically symmetric solutions of the Einstein-Maxwell gravity with the dilaton field are described. The solutions correspond to black holes and are generalizations of the previously known dilaton black hole solution. In addition to…
Realization of the stationary integral solutions of steady state transonic accretion flow in spherical symmetry helps to understand accretion phenomena on various astrophysical objects. In recent years, attempts have been made to study…
The dynamics of a black hole traveling through a plasma--a general relativistic extension of the classic Bondi-Hoyle-Lyttleton (BHL) accretion problem--can be related to a variety of astrophysical contexts, including the aftermath of binary…
We study some general properties of two black hole solutions in Einstein's conformal gravity. Both solutions can be obtained from the Kerr metric with a suitable conformal rescaling, which leads, respectively, to a regular and a singular…