Scalar perturbations of a single-horizon regular black hole
We investigate the massless scalar field perturbations, including the quasinormal mode spectrum and the ringdown waveform, of a regular black hole spacetime that was derived via the Loop Quantum Gravity inspired polymer quantization of spherical $4$D black holes. In contrast to most, if not all, of the other regular black holes considered in the literature, the resulting nonsingular spacetime has a single bifurcative horizon and hence no mass inflation. In the interior, the areal radius decreases to a minimum given by the Polymerization constant, $k$, and then re-expands into a Kantowski-Sachs universe. We find indications that this black hole model is stable against small scalar perturbations. We also show that an increase in the magnitude of $k$ will decrease the height of the QNM potential and gives oscillations with lower frequency and less damping.