Gravitational field around a screwed superconducting cosmic string in scalar-tensor theories

TL;DR

This paper derives the gravitational field of a screwed superconducting cosmic string within scalar-tensor theories, analyzing torsion effects on spacetime, particle motion, and matter accretion, highlighting differences from torsion-free scenarios.

Contribution

It provides a new solution for SSCS in scalar-tensor theories with torsion and explores its physical implications, including torsion's influence on gravity and matter dynamics.

Findings

Torsion modifies the spacetime structure around the string.

Torsion propagates outside the string when spin vanishes.

Matter accretion and wake formation are affected by torsion.

Abstract

We obtain the solution that corresponds to a screwed superconducting cosmic string (SSCS) in the framework of a general scalar-tensor theory including torsion. We investigate the metric of the SSCS in Brans-Dicke theory with torsion and analyze the case without torsion. We show that in the case with torsion the space-time background presents other properties different from that in which torsion is absent. When the spin vanish, this torsion is a $\phi$-gradient and then it propagates outside of the string. We investigate the effect of torsion on the gravitational force and on the geodesics of a test-particle moving around the SSCS. The accretion of matter by wakes formation when a SSCS moves with speed $v $ is investigated. We compare our results with those obtained for cosmic strings in the framework of scalar-tensor theory.