Nonlinear extensions of gravitating dyons: from NUT wormholes to Taub-Bolt instantons

TL;DR

This paper extends nonlinear electromagnetism coupled with gravity to include dyonic black holes with varied horizon topologies and magnetic mass, constructing AdS wormholes and analyzing their thermodynamics and phase transitions.

Contribution

It introduces a generalized family of dyonic black holes in nonlinear electrovacuum, including NUT wormholes and Taub-Bolt instantons, with new topological and magnetic features.

Findings

Phase transition between nut and bolt configurations similar to Maxwellian case.

Construction of AdS wormholes using Taub-NUT spaces.

Thermodynamic analysis indicating phase transitions.

Abstract

Recent work has shown the existence of a unique nonlinear extension of electromagnetism which preserves conformal symmetry and allows for the freedom of duality rotations. Moreover, black holes and gravitational waves have been found to exist in this nonlinearly extended electrovacuum. We generalise these dyonic black holes in two major ways: with the relaxation of their horizon topology and with the inclusion of magnetic mass. Motivated by recent attention to traversable wormholes, we use this new family of Taub-NUT spaces to construct AdS wormholes. We explore some thermodynamic features by using a semi-classical approach. Our results show that a phase transition between the nut and bolt configurations arises in a similar way to the Maxwellian case.