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arXiv · 2508.17993

Nonlinearities of Schwarzschild Black Hole Head-on Collisions

Alex Kehagias·Davide Perrone·Antonio Riotto
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Abstract

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.

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Alex Kehagias, Davide Perrone, Antonio Riotto. 2025-08-25. Nonlinearities of Schwarzschild Black Hole Head-on Collisions. https://arxiv.org/abs/2508.17993

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