相关论文: Ringdown nonlinearities in the eikonal regime
We investigate quadratic quasinormal mode coupling in black hole spacetime through numerical simulations of single perturbed black holes using both numerical relativity and second-order black hole perturbation theory. Focusing on the…
We study characteristic (quasinormal) modes of a $D$-dimensional Schwarzshild black hole. It proves out that the real parts of the complex quasinormal modes, representing the real oscillation frequencies, are proportional to the product of…
Quasinormal modes (QNMs) uniquely describe the dominant piece of the gravitational-wave ringdown of postmerger black holes. While the linear QNM regime has been extensively studied, recent work has highlighted the importance of…
We investigate the quasinormal modes of several families of higher-dimensional regular black holes arising in gravitational theories that incorporate an infinite tower of higher-curvature corrections to Einstein gravity. Our analysis…
We study second order gravitational perturbations on plane wave spacetimes from both the metric and curvature perturbation points of view. For the former, we explicitly use the isometries of the background to introduce tensor oscillator…
We compute the spectrum of quasinormal frequencies of regular black holes obtained in the presence of Non-Linear Electrodynamics. In particular, we perturb the black hole with a minimally coupled massive scalar field, and we study the…
We revisit the peculiar electromagnetic quasinormal mode spectrum of an asymptotically anti-de Sitter Schwarzschild black hole. Recent numerical calculations have shown that some quasinormal mode frequencies become purely overdamped at some…
Linear field perturbations of a black hole are described by the Green function of the wave equation that they obey. After Fourier decomposing the Green function, its two natural contributions are given by poles (quasinormal modes) and a…
We investigate the quasinormal modes of the Reissner$-$Nordstr\"om anti$-$de Sitter black hole using the Penrose limit, motivated by the geometrical optics approximation. This approach offers a novel framework for approximating quasinormal…
We study analytically quasinormal modes in a wide variety of black hole spacetimes, including $d$--dimensional asymptotically flat spacetimes and non-asymptotically flat spacetimes (particular attention has been paid to the four dimensional…
In a recent series of papers we have shown how the eikonal/geometrical optics approximation can be used to calculate analytically the fundamental quasinormal mode frequencies associated with coupled systems of wave equations, which arise,…
We investigate quasinormal ringing in both time and frequency domains for scalar and neutrino perturbations around black hole solutions that simultaneously describe regular and extreme configurations within a non-linear electrodynamics…
Recently, an exact black hole solution in non-minimal Einstein-Yang-Mills theory was obtained, and its quasinormal modes were subsequently analyzed using the JWKB approximation \cite{Gogoi:2024vcx}. However, we demonstrate that this…
We compute the quasinormal frequencies for scalar and electromagnetic perturbations of an improved Schwarzschild geometry in the framework of asymptotically safe gravity, which is one of the approaches to quantum gravity. Adopting the…
The large dimension ($D$) limit of general relativity has been used in problems involving black holes as an analytical approximation tool. Further it has been proposed that both linear and nonlinear problems involving black holes can be…
We study the even-parity $\ell=2$ perturbations of a Schwarzschild black hole to second order. The Einstein equations can be reduced to a single linear wave equation with a potential and a source term. The source term is quadratic in terms…
Black hole `spectroscopy', i.e. the identification of quasinormal mode frequencies via gravitational wave observations, is a powerful technique for testing the general relativistic nature of black holes. In theories of gravity beyond…
We investigate the nonlinear evolution of black hole ringdown in the framework of higher-order metric perturbation theory. By solving the initial-value problem of a simplified nonlinear field model analytically as well as numerically, we…
The nonlinear nature of general relativity manifests prominently throughout the merger of two black holes, from the inspiral phase to the final ringdown. Notably, the quasi-normal modes generated during the ringdown phase display…
It has long been known that null unstable geodesics are related to the characteristic modes of black holes-- the so called quasinormal resonances. The basic idea is to interpret the free oscillations of a black hole in the eikonal limit in…