Construction of Regular Black Holes in General Relativity
Zhong-Ying Fan, Xiaobao Wang
TL;DR
The paper develops a general, analytically tractable method to construct exact, regular black hole solutions in General Relativity coupled to nonlinear electrodynamics, using a mass-function f=1-2m(r)/r and a L(F) that supports magnetic or electric charges. By selecting appropriate mass profiles, three explicit magnetically charged regular classes (Bardeen, Hayward, and a new class) plus a generic case are obtained, with regularity requiring μ≥3 and a two-parameter structure tied to a magnetic charge; the framework is extended to electric charges, Legendre-transformed Lagrangians, and thermodynamics, including a first law, Smarr relations, and entropy products. The authors further generalize to asymptotically anti-de Sitter spacetimes, deriving AdS BH solutions and an extended phase-space thermodynamics with pressure-like variables, enabling exploration of critical behavior. Overall, the work provides a unified, constructive approach to regular black holes in GR with nonlinear electrodynamics and analyzes their global, thermodynamic, and AdS properties.
Abstract
We present a general procedure for constructing exact black hole solutions with electric or magnetic charges in General Relativity coupled to a nonlinear electrodynamics. We obtain a variety of two-parameter family spherically symmetric black hole solutions. In particular, the singularity at the central of the space-time can be cancelled in the parameters space and the black hole solutions become regular everywhere in the space-time. We study the global properties of the solutions and derive the first law of thermodynamics. We also generalize the procedure to include a cosmological constant and construct regular black hole solutions that are asymptotic to anti-de Sitter space-time.
