Quasinormal modes and strong cosmic censorship in the regularised 4D Einstein–Gauss–Bonnet gravity

The fate of strong cosmic censorship is ultimately linked to the extendibility of perturbation across the Cauchy Horizon and known to be violated in the near extremal region of a charged de Sitter black hole. Similar violations can also be realized in higher curvature theories, with the strength of violation becoming stronger as compared to general relativity. In this work, we extend this analysis further to study the validity of strong cosmic censorship conjecture in the context of the regularised four-dimensional Einstein Gauss–Bonnet theory with respect to both scalar and electromagnetic perturbation. We also study the late time tails of scalar fields.