Spinning loop black holes

Abstract

In this paper, we construct four Kerr-like spacetimes starting from the loop black hole (LBH) Schwarzschild solutions and applying the Newman–Janis transformation. In previous papers, the Schwarzschild LBH was obtained replacing the Ashtekar connection with holonomies on a particular graph in a minisuperspace approximation which describes the black hole interior. Starting from this solution, we use a Newman–Janis transformation and restrict our study to two different and natural complexifications inspired from the complexifications of the Schwarzschild and Reissner–Nordström metrics. We show explicitly that the spacetimes obtained in this way are singularity free and thus there are no naked singularities. We show that the transformation moves, if any, the causality violating regions of the Kerr metric far from r = 0. We study the spacetime structure paying particular attention to the shape of the horizons. We conclude the paper with a discussion on a regular Reissner–Nordström black hole derived from the Schwarzschild LBH and then apply again the Newmann–Janis transformation.