Massive scalar field perturbations of 4D de Sitter–Einstein-Gauss-Bonnet black holes
Phys. Rev. D 111, 124013 – Published 10 June, 2025
DOI: https://doi.org/10.1103/y33s-2hd1
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 gives rise to three branches of modes: the perturbative (in ) Schwarzschild branch, the perturbative (in ) dS branch, and a nonperturbative (in ) 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 nonperturbative dS branch of modes, absent when , emerges as a novel feature of the Einstein-Gauss-Bonnet framework.