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arXiv · 2103.11156

Spherically symmetric perturbations of a Schwarzschild black hole in torsion bigravity

Vasilisa Nikiforova
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Abstract

Time-dependent spherically-symmetric perturbations of Schwarzschild black holes are studied within torsion bigravity, i.e., within generalized Einstein-Cartan theories where the dynamical torsion carries massive spin-2 excitation. We reduce linearized perturbations to a Zerilli-like equation. The structure of the potential entering the latter Zerilli-like equation has two important consequences. First, in order to avoid the presence of singularities in generic perturbations, one must restrict the range (or inverse mass) of the spin-2 excitation to be (essentially) smaller than the radius of the considered black hole. Second, we then show that the Schwarzschild black hole is linearly stable against spherically-symmetric perturbations.

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Vasilisa Nikiforova. 2021-03-20. Spherically symmetric perturbations of a Schwarzschild black hole in torsion bigravity. https://doi.org/10.1103/physrevd.104.024032

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