Nonlinearities of Schwarzschild Black Hole Head-on Collisions
General Relativity and Quantum Cosmology2025-08-26v1Cosmology and Nongalactic AstrophysicsHigh Energy Physics - PhenomenologyHigh Energy Physics - Theory
We derive analytically the amplitude of the quadratic quasi-normal mode generated in the ringdown stage of the gravitational waveform produced by the ultra-relativistic head-on collision of two non-spinning Schwarzschild black holes. Although being a highly nonlinear event, second-order perturbation theory suffices and that nonlinearities may be derived by a simple bootstrapping procedure.
@article{arxiv.2508.17993,
title = {Nonlinearities of Schwarzschild Black Hole Head-on Collisions},
author = {Alex Kehagias and Davide Perrone and Antonio Riotto},
journal= {arXiv preprint arXiv:2508.17993},
year = {2025}
}