Electromagnetic radiation generated by a charged particle falling radially into a Schwarzschild black hole: A complex angular momentum description

Quasinormal mode frequencies of Kerr black holes from Regge trajectories

“…We hope that the results obtained in this paper and in previous ones [41,[46][47][48][49][50][62][63][64][65][66][67][68][69][70][71] as well as the aforemen-tioned avenues would stimulate research in incorporating Regge pole theory into modern gravitational physics and, in particular, in the fields of strong lensing and BH spectroscopy.…”

“…This is due to the fact that it has been the subject of relatively few studies. However, for the Schwarzschild BH, we know that it provides an effective resummation of the partial wave expansion defining the retarded Green's function which can reproduce with very good agreement the quasinormal ringdown without requiring a starting time, as well as, in certain circumstances, the tail of the signal and the preringdown phase with rather good agreement [69,70]. In Sec.…”

“…It is interesting to recall that the success of CAM techniques is due to their ability to provide effective resummations of partial wave sums and to extract from them the hidden information, which leads to a clear description of physical processes. In the context of BH physics, these techniques have permitted to make significant contributions in scattering dynamics [62][63][64][65][66][67][68] and to revisit from an alternative point of view radiation phenomenons [69,70].…”

“…This provides a compact expression for the late-time tail of the retarded Green's function which includes all the multipolar contributions and, in addition, this partially explains the superiority of the Regge pole approximation over the quasinormal approximation, a fact already noted in Refs. [69,70]. 5 It should be noted that, in previous works [46,48], we labelled the Regge poles of the Schwarzschild BH from n = 1.…”