Alexandre M. Pombo, "A Hybrid Pseudo-spectral–PINN Approach to Black Hole Quasinormal Modes"

Tuesday 14 Apr 2026, 16:00 → 18:00 Asia/Seoul

 "Gravitational-wave detections by the LIGO-Virgo-KAGRA network have 
turned compact-object mergers into precision probes of strong gravity. 
The post-merger ringdown is particularly incisive: it is governed by 
quasinormal modes (QNMs), the damped oscillations that encode the 
remnant's structure and provde a fingerprint of the final object. While 
current detectors constrain the dominant mode, next-generation 
observatories will resolve multiple modes with high precision, placing 
stringent demands on the accuracy of theoretical predictions. Computing 
QNMs for rotating black holes is, however, a non-trivial task, as it 
requires solving highly coupled, complex-valued perturbation equations 
where standard methods struggle. In this talk, I present SpectralPINN, a 
hybrid solver combining Pseudo-spectral methods with Physics-Informed 
Neural Networks, validated at 10⁻⁵ relative accuracy. I will present 
results for Kerr and Kerr-Newman black holes, demonstrating the method's 
robustness and accuracy across parameter space, and discuss its 
potential for extension to more exotic compact objects relevant to 
next-generation detector science."