Optimal extraction of information from gravitational-wave observations of binary black-hole coalescences requires detailed knowledge of the waveforms. Current approaches for representing waveform information are based on spin-weighted spherical harmonic decomposition. Higher-order harmonic modes carrying a few percent of the total power output near merger can supply information critical to dete...

Numerical relativity has recently yielded a plethora of results about kicks from spinning mergers which has, in turn, vastly increased our knowledge about the spin interactions of black hole systems. In this work we use black hole perturbation theory to calculate accurately the gravitational waves emanating from the end of the plunging stage of an extreme mass ratio merger in order to further u...

Recently a renormalizable model of gravity has been proposed, which may be a UV completion of General Relativity (GR) or its infra-red modification. Although a generic vacuum of the theory is anti-de Sitter one, particulars limit of the theory allow for the Minkowski vacuum. In this limit post-Newtonian coefficients coincide with those of the pure General Relativity. Thus the deviations from th...

We consider the BTZ black hole surrounded by the conformal scalar field. Within general relativity, the resonant quasinormal (QN) modes dominate in the response of a black hole to external perturbations. At the same time, the metric of an evaporating black hole is affected by the Hawking radiation. We estimate the shift in the quasinormal spectrum of the BTZ black hole stipulated by the back re...

A new algorithm for computing the accurate values of quasinormal frequencies of extremal Reissner-Nordström black holes is presented. The numerically computed values are consistent with the values earlier obtained by Leaver and those obtained through the WKB method. Our results are more precise than other results known to date. We also find a curious fact that the resonant frequencies of gravit...

We show that strongly coupled field theories with holographic gravity duals at finite charge density and low temperatures can undergo de Haas van Alphen quantum oscillations as a function of an external magnetic field. Exhibiting this effect requires computation of the one loop contribution of charged bulk fermions to the free energy. The one loop calculation is performed using a formula expres...

We calculate the quasinormal modes (QNMs) for gravitational perturbations of the Schwarzschild black hole in the five dimensional (5D) spacetime with a continued fraction method. As shown by Kodama and Ishibashi, the gravitational perturbations of higher-dimensional (higher-D) Schwarzschild black holes can be divided into three decoupled classes, namely scalar-gravitational, vectorgravitational...