Force-Free Foliations

TL;DR

This paper introduces a novel method for identifying force-free electromagnetic field configurations by focusing on the foliation of spacetime, leading to new solutions relevant for plasma physics and astrophysics.

Contribution

It develops a general foliation-based approach to find force-free fields, providing new stationary and axisymmetric solutions including a potential plasma vortex model.

Findings

New stationary force-free solutions discovered

Method applicable to astrophysical plasma configurations

Potential modeling of plasma vortices near magnetic nulls

Abstract

Electromagnetic field configurations with vanishing Lorentz force density are known as force-free and appear in terrestrial, space, and astrophysical plasmas. We explore a general method for finding such configurations based on formulating equations for the field lines rather than the field itself. The basic object becomes a foliation of spacetime or, in the stationary axisymmetric case, of the half-plane. We use this approach to find some new stationary and axisymmetric solutions, one of which could represent a rotating plasma vortex near a magnetic null point.