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arXiv · 2505.17161

Massive scalar field perturbations of 4D de Sitter Einstein-Gauss-Bonnet black holes

Ramón Bécar·P. A. González·Eleftherios Papantonopoulos·Yerko Vásquez
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Abstract

We investigate the propagation of massive scalar fields in the background of four-dimensional Einstein-Gauss-Bonnet black holes with de Sitter (dS) asymptotics. Our study focuses on the various branches of quasinormal modes present in this background, employing the pseudospectral Chebyshev method and the third-order Wentzel-Kramers-Brillouin approximation. We identify that the introduction of the Gauss-Bonnet coupling constant $α$ gives rise to three branches of modes: the perturbative (in $α$) Schwarzschild branch, the perturbative (in $α$) dS branch, and a non-perturbative (in $α$) dS branch. Our results show that the propagation of a massive scalar field is stable in this background. Furthermore, the Gauss-Bonnet coupling constant induces significant deviations in the Schwarzschild branch and smaller deviations in the perturbative dS branch compared to the corresponding branches in the Schwarzschild-dS limit. Additionally, the non-perturbative dS branch of modes, absent when $α=0$, emerges as a novel feature of the Einstein-Gauss-Bonnet framework.

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Ramón Bécar, P. A. González, Eleftherios Papantonopoulos, Yerko Vásquez. 2025-05-22. Massive scalar field perturbations of 4D de Sitter Einstein-Gauss-Bonnet black holes. https://doi.org/10.1103/y33s-2hd1

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