Charged black-bounce spacetimes

TL;DR

This paper explores the construction of charged black-bounce spacetimes that interpolate between regular black holes and wormholes, extending the Kerr-Newman family with minimal deviations and analyzing their geometric and physical properties.

Contribution

It introduces black-bounce-Reissner-Nordstr"om and black-bounce-Kerr-Newman spacetimes, providing new regular black hole mimickers with controlled deviations and examining their symmetries and matter content.

Findings

Existence of a Killing tensor and Carter-like constant in these spacetimes

These solutions smoothly interpolate between black holes and wormholes

Non-trivial matter/energy content is required under general relativity

Abstract

Given the recent development of rotating black-bounce-Kerr spacetimes, for both theoretical and observational purposes it becomes interesting to see whether it might be possible to construct black-bounce variants of the entire Kerr-Newman family. Specifically, herein we shall consider black-bounce-Reissner-Nordstr\"om and black-bounce-Kerr-Newman spacetimes as particularly simple and clean everywhere-regular black hole "mimickers" that deviate from the Kerr-Newman family in a precisely controlled and minimal manner, and smoothly interpolate between regular black holes and traversable wormholes. While observationally the electric charges on astrophysical black holes are likely to be extremely low, $|Q|/m \ll 1$, introducing any non-zero electric charge has a significant theoretical impact. In particular, we verify the existence of a Killing tensor (and associated Carter-like constant) but without the full Killing tower of principal tensor and Killing-Yano tensor, also we discuss how, assuming general relativity, the black-bounce-Kerr-Newman solution requires an interesting, non-trivial matter/energy content.