Magnetic point sources in three dimensional Brans-Dicke gravity theories

TL;DR

This paper constructs geodesically complete spacetimes with magnetic point sources in a 3D Brans-Dicke type Einstein-Maxwell-Dilaton theory, exploring the effects of different parameter values and source configurations.

Contribution

It provides explicit solutions for magnetic point sources in 3D Brans-Dicke gravity, generalizing known solutions and analyzing their physical interpretations.

Findings

Solutions reduce to magnetic BTZ when w=∞

w=0 case matches 4D GR with one Killing vector

Magnetic sources interpreted as superposed electric charges

Abstract

We obtain geodesically complete spacetimes generated by static and rotating magnetic point sources in an Einstein-Maxwell-Dilaton theory of the Brans-Dicke type in three dimensions (3D). The theory is specified by three fields, the dilaton, the graviton and the electromagnetic field, and two parameters, the cosmological constant and the Brans-Dicke parameter, w. When the Brans-Dicke parameter is infinity, our solution reduces to the magnetic counterpart of the BTZ solution, while the w=0 case is equivalent to 4D general relativity with one Killing vector. The source for the magnetic field can be interpreted as composed by a system of two symmetric and superposed electric charges. One of the electric charges is at rest and the other is spinning.