Thin shells joining local cosmic string geometries

TL;DR

This paper constructs and analyzes the stability of spacetimes with thin shells connecting different cosmic string geometries, including wormholes, under cylindrical symmetry-preserving perturbations.

Contribution

It introduces a theoretical model for joining local cosmic string geometries with thin shells and studies their stability, including non-symmetric wormhole configurations.

Findings

Static configurations can be stable for certain parameter values.

Both cosmic string and wormhole geometries are considered.

Stability depends on the shell parameters and geometry.

Abstract

In this article we present a theoretical construction of spacetimes with a thin shell that joins two different local cosmic string geometries. We study two types of global manifolds, one representing spacetimes with a thin shell surrounding a cosmic string or an empty region with Minkowski metric, and the other corresponding to wormholes which are not symmetric across the throat located at the shell. We analyze the stability of the static configurations under perturbations preserving the cylindrical symmetry. For both types of geometries we find that the static configurations can be stable for suitable values of the parameters.