相关论文: The Spectrum of Static Subtracted Geometries

We obtain explicit separable solutions of the wave equation of massless minimally coupled scalar fields in the subtracted geometry of four-dimensional rotating and Melvin (magnetised) four-charge black holes of the STU model, a consistent…

We consider the rotating non-extremal black hole of N=2 D=4 STU supergravity carrying three magnetic charges and one electric charge. We show that its subtracted geometry is obtained by applying a specific SO(4,4) Harrison transformation on…

Coherent quantum black holes are quantum geometries obtained by means of a mean-field-like approach to the gravitational interaction. This procedure attenuates the classical spacetime singularities of general relativity by replacing them…

We consider extremal limits of the recently constructed "subtracted geometry". We show that extremality makes the horizon attractive against scalar perturbations, but radial evolution of such perturbations changes the asymptotics: from a…

We determine hidden conformal symmetries behind the evolution equations of black hole perturbations in a vector-tensor theory of gravity. Such hidden symmetries are valid everywhere in the exterior region of a spherically symmetric,…

We study the vacuum polarization of a massless minimally coupled scalar field at the horizon of four-charge STU black holes. We compare the results for the standard asymptotically flat black holes and for the black holes obtained in the…

We carefully examine the exact analytic spectrum of quasinormal modes of general black holes in the so-called subtracted geometry of maximally supersymmetric supergravity. These black holes have the same area and surface gravity at both the…

We detail the construction of the most general asymptotically flat, stationary, rotating, non-extremal, dyonic black hole of the four-dimensional N=2 supergravity coupled to 3 vector multiplets that describes the STU model. It generates…

We embed Kerr-Newman-AdS black holes into $\mathcal{N} = 8$ gauged supergravity and study quadratic fluctuations around the black hole backgrounds of all fields in the larger theory. The equations of motion of the perturbations are…

We study, following Bertini et al. \cite{Bertini:2011ga}, the hidden conformal symmetry of the massless Klein-Gordon equation in the background of the general, charged, spherically symmetric, static black-hole solution of a class of…

This thesis is dedicated to the study of symmetries in reduced models of gravity, with some frozen degrees of freedom. We focus on the minisuperspace reduction whith a finite number of degrees of freedom. Minisuperspaces are treated as…

The spherically symmetric deformation of the Schwarzschild solution owing to the quantum corrections to gravity is known as Kazakov-Solodukhin black-hole metric. Neglecting non-spherical deformations of the background the problem was solved…

Quasinormal modes and frequencies are the eigenvectors and eigenvalues of a non-Hermitian differential operator. They hold crucial significance in the physics of black holes. The analysis of quasinormal modes of black holes in…

We show that the previously obtained subtracted geometry of four-dimensional asymptotically flat multi-charged rotating black holes, whose massless wave equation exhibit $SL(2,\R) \times SL(2,\R) \times SO(3)$ symmetry may be obtained by a…

This note includes results of a study of stationary spherically symmetric ``dark holes'', objects merging central black holes and peripheral scalar graviton dark haloes arising in the framework of the modified gravity -- the quartet-metric,…

In this note, we present a synopsis of geometric symmetries for (spin 0) perturbations around (4D) black holes and de Sitter space. For black holes, we focus on static perturbations, for which the (exact) geometric symmetries have the group…

We study the quasi-normal modes of a massless scalar field in a general sub-extreme Kerr back- ground by exploiting the hidden SL(2, R) x SL(2, R) x SO(3) symmetry of the subtracted geometry approximation. This faithfully models the near…

We obtain retarded Green's functions for massless scalar fields in the background of near-extreme, near-horizon rotating charged black holes of five-dimensional minimal gauged supergravity. The radial part of the (separable) massless…

We study the asymptotic behavior of the spherically symmetric solutions of the system obtained from the dimensional reduction of the six-dimensional Einstein- Gauss-Bonnet action. We show that in general the scalar field that parametrizes…

We investigate the complete family of (aligned) Robinson-Trautman spacetimes sourced by conformally invariant non-linear electrodynamics in $D$ dimensions in the presence of an arbitrary cosmological constant. After presenting general…