Quantum Improved Regular Kerr Black Holes

TL;DR

This paper investigates quantum modifications to Kerr black holes within asymptotically safe gravity, leading to regular, thermodynamically consistent rotating black holes that resolve singularities and reduce closed time-like curves.

Contribution

It introduces a mass-dependent scale identification for quantum Kerr black holes and demonstrates their regularity, thermodynamic consistency, and improved causal structure.

Findings

Black holes are regular with no ring singularity.

Thermodynamics at the horizon is consistent.

Closed time-like curves are partially eliminated.

Abstract

We study the quantum improvement of Kerr black holes with mass-dependent scale identifications in asymptotically safe gravity. We find that a physically sensible identification can only be a function of $Mr$ and the area $A=4\pi(r^2+a^2)$ where $M$ is the mass of the black hole and $a$ is an angular momentum parameter. We then discuss various properties of the rotating quantum black holes for a simple choice of the identification. We show that the resulting regular rotating black holes have the following nice properties: (i) admitting a consistent black hole thermodynamics at the horizon, (ii) resolving the ring singularity, (iii) partially eliminating closed time-like curves present in the classical Kerr black holes.