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arXiv · 2504.06224

Nonlinear Tails of Gravitational Waves in Schwarzschild Black Hole Ringdown

Alex Kehagias·Antonio Riotto
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Abstract

Schwarzschild black holes evolve toward their static configuration by emitting gravitational waves, which decay over time following a power law at fixed spatial positions. We derive this power law analytically for the second-order even gravitational perturbations, demonstrating that it is determined by the fact that the second-order source decays as the inverse square of the distance. Quadratic gravitational modes with multipole $\ell$ decay according to a law $\sim t^{-2\ell-1}$, in contrast to the linear Price law scaling $\sim t^{-2\ell-3}$. Consequently, nonlinear tails may persist longer than their linear counterparts.

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Alex Kehagias, Antonio Riotto. 2025-04-08. Nonlinear Tails of Gravitational Waves in Schwarzschild Black Hole Ringdown. https://arxiv.org/abs/2504.06224

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