Local cosmic string in generalised scalar tensor theory

TL;DR

This paper demonstrates that local gauge cosmic strings are consistent within a generalized scalar-tensor theory where the coupling parameter varies with the scalar field, providing new solutions to Einstein's equations for such strings.

Contribution

It introduces a generalized scalar-tensor framework where the coupling parameter depends on the scalar field, and derives solutions for the interior of local gauge cosmic strings.

Findings

Cosmic strings are consistent in the generalized scalar-tensor theory.

Explicit solutions for the interior of such strings are obtained.

The theory extends the applicability of cosmic string models beyond Brans-Dicke theory.

Abstract

A recent investigation shows that a local gauge string with a phenomenological energy momentum tensor, as prescribed by Vilenkin, is inconsistent in Brans-Dicke theory. In this work it has been shown that such a string is consistent in a more general scalar tensor theory where $\omega$ is function of the scalar field.A set of solutions of full nonlinear Einstein's equations for interior region of such a string are presented.