Scalar perturbations of black holes in Jackiw-Teitelboim gravity

Abstract

We study linear scalar perturbations of black holes in two space-time dimensional (2D) gravity models with particular emphasis on Jackiw-Teitelboim (JT) gravity. We obtain an exact expression for the quasinormal mode frequencies for single horizon JT black holes and then verify it numerically using the Horowitz-Hubeny method. For a 2D Reissner-Nordstr\"om like solution, we find that the scalar wave equation reduces to the confluent Heun equation using which we calculate the quasi-frequencies. Finally, we consider the dimensionally reduced BTZ black hole and obtain the exterior and interior quasinormal modes. The dynamics of a scalar field near the Cauchy horizon mimics the behaviour of the same for the BTZ black hole, indicating a possible violation of strong cosmic censorship conjecture in near extreme limit. However, quantum effects seem to rescue strong cosmic censorship.