Dilatonic, Current-Carrying Cosmic String

TL;DR

This paper investigates how scalar-tensor gravity theories affect the spacetime structure and light propagation around superconducting cosmic strings, providing insights into potential observable deviations from general relativity.

Contribution

It derives the metric of a superconducting cosmic string within scalar-tensor gravity in the weak-field limit and analyzes light behavior in this modified spacetime.

Findings

Scalar-tensor modifications alter the cosmic string metric

Light deflection is affected by scalar fields

Results suggest potential observational signatures

Abstract

We study the implications of a scalar-tensorial gravity for the metric of an isolated self-gravitating superconducting cosmic string. These modifications are induced by an arbitrary coupling of a massless scalar field to the usual tensorial field in the gravitational Lagrangian. We derive the metric in the weak-field approximation and we analyse the behaviour of light in this spacetime. We end with some discussions.