3 papers
gr-qc2026
Ringdown and echoes from compact objects: Debye series and Debye quasinormal modes
Mohamed Ould El Hadj, Sam R. Dolan
We introduce a new series decomposition of the waveform constructed in the spirit of Debye expansions in scattering theory, and we use this to analyse the time-domain response of c…
gr-qc2026
Scattering from compact objects: Debye series and Regge-Debye poles
Mohamed Ould El Hadj
We investigate elastic scattering by a compact, horizonless body in curved spacetime, considering a massless scalar wave incident on a static, spherically symmetric, uniform-densit…
gr-qc2025
Black hole absorption cross sections: Spin and Regge poles
Mohamed Ould El Hadj
We investigate the absorption of massless scalar, electromagnetic, and gravitational fields propagating in the Schwarzschild black hole geometry. Using complex angular momentum tec…