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Linearized perturbations of a Schwarzschild black hole are described, for each angular momentum $ell$, by the well-studied discrete quasinormal modes (QNMs), and in addition a continuum. The latter is characterized by a cut strength $q(gamma>0)$ for frequencies $omega = -igamma$. We show that: (a) $q(gammadownarrow0) propto gamma$, (b) $q(Gamma) = 0$ at $Gamma = (ell+2)!/[6(ell-2)!]$, and (c) $q(gamma)$ oscillates with period $sim 1$ ($2Mequiv1$). For $ell=2$, a pair of QNMs are found beyond the cut on the unphysical sheet very close to $Gamma$, leading to a large dipole in the Greens function_near_ $Gamma$. For a source near the horizon and a distant observer, the continuum contribution relative to that of the QNMs is small.
We study the spectrum of the bound state perturbations in the interior of the Schwarzschild black hole for the scalar, electromagnetic and gravitational perturbations. Demanding that the perturbations to be regular at the center of the black hole det
Black hole perturbation theory is typically studied on time surfaces that extend between the bifurcation sphere and spatial infinity. From a physical point of view, however, it may be favorable to employ time surfaces that extend between the future e
We study linear gravitational perturbations of Schwarzschild spacetime by solving numerically Regge-Wheeler-Zerilli equations in time domain using hyperboloidal surfaces and a compactifying radial coordinate. We stress the importance of including the
We derive a set of coupled equations for the gravitational and electromagnetic perturbation in the Reissner-Nordstrom geometry using the Newman Penrose formalism. We show that the information of the physical gravitational signal is contained in the W
In this work, we have calculated the polar gravitational quasinormal modes for a quantum corrected black hole model, that arises in the context of Loop Quantum Gravity, known as Self-Dual Black Hole. In this way, we have calculated the characteristic