New Singular and Nonsingular Colliding Wave Solutions in Einstein - Maxwell - Scalar Theory

TL;DR

This paper introduces a method to generate coupled scalar field solutions in colliding Einstein-Maxwell waves, enabling the construction of nonsingular solutions depending on the scalar field choice, with implications for singularity behavior.

Contribution

The paper presents a novel technique to generate coupled scalar field solutions in colliding Einstein-Maxwell waves using the Bell-Szekeres solution as a seed, allowing for nonsingular configurations.

Findings

Nonsingular solutions can be constructed depending on the scalar field chosen.

Adding scalar fields does not improve singularities in already singular Einstein-Maxwell solutions.

Scalar fields transformable to spherical symmetry tend to have singularities.

Abstract

A technique is given to generate coupled scalar field solutions in colliding Einstein - Maxwell (EM) waves. By employing the Bell - Szekeres solution as seed and depending on the chosen scalar field it is possible to construct nonsingular solutions. If the original EM solution is already singular addition of scalar fields does not make the physics any better. In particular, scalar field solution that is transformable to spherical symmetry is plagued with singularities.