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arXiv · 0803.0501

Possible discovery of a nonlinear tail and second-order quasinormal modes in black hole ringdown

Satoshi Okuzumi·Kunihito Ioka·Masa-aki Sakagami
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Abstract

We investigate the nonlinear evolution of black hole ringdown in the framework of higher-order metric perturbation theory. By solving the initial-value problem of a simplified nonlinear field model analytically as well as numerically, we find that (i) second-order quasinormal modes (QNMs) are indeed excited at frequencies different from those of first-order QNMs, as predicted recently. We also find serendipitously that (ii) late-time evolution is dominated by a new type of power-law tail. This ``second-order power-law tail'' decays more slowly than any late-time tails known in the first-order (i.e., linear) perturbation theory, and is generated at the wavefront of the first-order perturbation by an essentially nonlinear mechanism. These nonlinear components should be particularly significant for binary black hole coalescences, and could open a new precision science in gravitational wave studies.

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Satoshi Okuzumi, Kunihito Ioka, Masa-aki Sakagami. 2008-06-04. Possible discovery of a nonlinear tail and second-order quasinormal modes in black hole ringdown. https://doi.org/10.1103/physrevd.77.124018

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