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arXiv · 0909.5558

Self-force and motion of stars around black holes

A. Spallicci·S. Aoudia
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Abstract

Through detection by low gravitational wave space interferometers, the capture of stars by supermassive black holes will constitute a giant step forward in the understanding of gravitation in strong field. The impact of the perturbations on the motion of the star is computed via the tail, the back-scattered part of the perturbations, or via a radiative Green function. In the former approach, the self-force acts upon the background geodesic, while in the latter, the geodesic is conceived in the total (background plus perturbations) field. Regularisations (mode-sum and Riemann-Hurwitz $ζ$ function) intervene to cancel divergencies coming from the infinitesimal size of the particle. The non-adiabatic trajectories require the most sophisticated techniques for studying the evolution of the motion, like the self-consistent approach.

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A. Spallicci, S. Aoudia. 2009-09-30. Self-force and motion of stars around black holes. https://arxiv.org/abs/0909.5558

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