Nonstatic global string in Brans-Dicke theory

TL;DR

This paper investigates the gravitational field of a dynamic global string within Brans-Dicke theory, revealing the presence of gravitational radiation and singularities, and analyzing the spacetime structure.

Contribution

It introduces a model with nonseparable metric and scalar field functions, exploring dynamic global strings in Brans-Dicke gravity, which is a novel approach.

Findings

Spacetime can have or lack singularities at finite distances from the string core.

The spacetime exhibits both outgoing and incoming gravitational radiation.

Singularity at a specific time persists regardless of spatial behavior.

Abstract

Gravitational field of a nonstatic global string has been studied in the context of Brans-Dicke theory of gravity. Both the metric components and the BD scalar field are assumed to be nonseparable functions of time and space.The spacetime may or may not have any singularity at a finite distance from the string core but the singularity at a particular time always remains. It has been shown that the spacetime exhibits both outgoing and incoming gravitational radiation.