$U(1)$ local strings in generalized hybrid metric-Palatini gravity

TL;DR

This paper investigates $U(1)$ local cosmic string solutions within a generalized hybrid metric-Palatini gravity framework, deriving exact and numerical solutions, and identifying stable configurations influenced by scalar fields and potentials.

Contribution

It introduces a detailed analysis of $U(1)$ local string solutions in hybrid metric-Palatini gravity, including exact and numerical solutions and stability analysis.

Findings

Multiple stable string configurations identified

Solutions depend on scalar potential and boundary conditions

Exact solutions found for specific potential forms

Abstract

In this work we will explore $U(1)$ local cosmic string solutions in the context of the generalized hybrid metric-Palatini theory of gravity in its scalar-tensor representation. Using a general static cylindrically symmetric metric to find the dynamical equations for this particular case, we will simplify the equations by imposing boost invariance along $t$ and $z$ directions. The strings properties are determined by both scalar fields and by the effective potential, function of the scalar fields. While for some forms of the potential, the dynamical equations can be solved exactly, for more general forms of the potential the solutions are found numerically. Several stable string configurations were found, whose basic parameters depend essentially on the effective field potential, and on the boundary conditions.