# Non-singular quantum improved rotating black holes and their maximal extension

## TL;DR

This paper introduces a modified Newman-Janis algorithm to derive non-singular, maximally extended rotating black hole solutions from quantum improved static black holes, eliminating singularities and analyzing their causal structure.

## Contribution

It presents a novel prescription for extending static quantum black holes to rotating ones without singularities, and thoroughly examines their horizons and causal diagrams.

## Key findings

- The quantum improved rotating black holes are free of scalar curvature singularities.
- The horizons and causal structures resemble those of classical Kerr black holes.
- Penrose diagrams illustrate the maximal extension of these non-singular spacetimes.

## Abstract

We add a prescription to the Newman-Janis algorithm in order to use it as a means of finding new extended (`through r<0') rotating black hole spacetimes from static spherically symmetric ones. Then, we apply the procedure to a quantum improved black hole spacetime coming from Quantum Einstein Gravity. The goal is to get a maximally extended spacetime corresponding to a non-singular rotating black hole emulating the standard maximally extended Kerr black hole in regions where quantum effects are negligible. We rigourously check for the existence of scalar curvature singularities in the quantum improved rotating spacetime and we show that it is devoid of them. We also analyze the horizons and causal structure of the rotating black hole and provide Penrose diagrams for the maximally extended spacetime.