相关论文: Spectroscopy of Stringy Black Hole

Microscopic black holes are sensitive to higher dimension operators in the gravitational action. We compute the influence of these operators on the Schwarzschild solution using perturbation theory. All (time reversal invariant) operators of…

In this paper, we study the quasinormal modes(QNMs) of massless scalar perturbations to probe the Van der Waals like small and large black holes(SBH/LBH) phase transition of (charged) AdS black holes in the 4-dimensional Einstein…

Black holes hold a tremendous discovery potential. In this paper the extent to which the Event Horizon Telescope and its next generation upgrade can resolve their structure is quantified. Black holes are characterized by a perfectly…

We investigate the correspondence between the variability seen in the stellar and supermassive black holes. Galactic Black Hole (GBH) power density spectra (PDS) are generally complex, and dependent on spectral state. In the low/hard state…

In this work we generalize the results for the entropy spectra typically derived for black holes in general relativity to a generic horizon within the spherically symmetric (asymptotically flat and non-flat) space-times of more general…

We develop a geometry-first model that maps measured thin-disk water megamaser observables--sky angles, frequency shifts, their secular drifts and the angular redshift rate--to the black hole parameters in a generic static, spherically…

The role of horizon area quantization on black hole thermodynamics is investigated in this article. The coefficient appearing in the quantization of area is fixed by an appeal to the saturated form of the Landauer's principle. Then by…

While grey-body factors for a test scalar field in stringy black holes described by the renowned Gibbons-Maeda-Garfinkle-Horowitz-Strominger (GMGHS) solution have been analyzed in the literature, no such analysis exists for gravitons,…

Local and non-local properties of Hawking radiation in the presence of short distance dispersion are computed using connection formulae. The robustness of the spectrum and that of the two-point function are explained by showing that the…

Spectropolarimetric efforts in the last few years have provided an efficient method that is based on the profiles of the polarization plane position angle of broad emission lines in active galactic nuclei (AGNs). Here we present black hole…

Path integral methods are used to derive a general expression for the entropy of a black hole in a diffeomorphism invariant theory. The result, which depends on the variational derivative of the Lagrangian with respect to the Riemann…

We measure the black hole mass in the nearby active galaxy Centaurus A (NGC 5128) using a new method based on spectroastrometry of a rotating gas disk. The spectroastrometric approach consists in measuring the photocenter position of…

The entropy of the Reissner-N\"{o}rdstrom black hole is studied within the context of a brane-world scenario. Such a black hole is a solution of the Einstein field equations on the brane, possessing a tidal charge which is a reflection of…

Some basic features of black-hole statistical mechanics are investigated, assuming that black holes respect the principles of quantum mechanics. Care is needed in defining an entropy S_bh corresponding to the number of microstates of a…

The Event Horizon Telescope (EHT) has imaged the shadow of the supermassive black hole in M87. A library of general relativistic magnetohydrodynamics (GMRHD) models was fit to the observational data, providing constraints on black hole…

The merger of colliding black holes (BHs) should lead to the production of ringdown or quasinormal modes (QNMs), which may very well be sensitive to the state of the interior. We put this idea to the test with a recent proposal that the…

We review a General Relativistic (GR) method to determine the black hole (BH) parameters: mass-to-distance ratio, position and recessional velocity of active galactic nuclei (AGNs) of Seyfert type, which have an accretion disk with water…

Deep conceptual problems associated with classical black holes can be addressed in string theory by the ``fuzzball'' paradigm, which provides a microscopic description of a black hole in terms of a thermodynamically large number of regular,…

We present new H and K bands spectroscopy of 15 high luminosity active galactic nuclei (AGNs) at redshifts 2.3-3.4 obtained on Gemini South. We combined the data with spectra of additional 29 high-luminosity sources to obtain a sample with…

Recent detailed analysis within the Loop Quantum Gravity calculation of black hole entropy shows a stair-like structure in the behavior of entropy as a function of horizon area. The non-trivial distribution of the degeneracy of the black…