The Stability of Asymmetric Cylindrical Thin-Shell Wormholes

TL;DR

This paper investigates the stability of asymmetric cylindrical thin-shell wormholes constructed from various cylindrically symmetric spacetimes, analyzing how asymmetry affects their mechanical stability and revealing that symmetric states are not always the most stable.

Contribution

It introduces a generic formulation for asymmetric cylindrical thin-shell wormholes and examines their stability, highlighting the impact of asymmetry and equations of state on their stability properties.

Findings

Stability varies with the degree of asymmetry.

Symmetric states are not necessarily the most stable.

Radius-dependent equations of state significantly influence stability.

Abstract

In continuation of a preceding work on introducing asymmetric thin-shell wormholes as an emerging class of traversable wormholes within the context, this time cylindrically symmetric spacetimes are exploited to construct such wormholes. Having established a generic formulation, first the Linet-Tian metric generally, and then the cosmic string metric and a black string metric in greater details are studied as constructing blocks of cylindrical asymmetric thin-shell wormholes. The corresponding wormholes are investigated within the linearized stability analysis framework to firstly, demonstrate that they can exist from the mechanical stability point of view, and secondly, indicate the correlation between the stability and symmetry in each case, if there is any at all. From here, we have extracted a pattern for the way stability changes with the asymmetry degree for the two examples; however, it was observed that the symmetric state is not the most neither the less stable state. There are also some side results: It was learned that any cylindrical thin-shell wormhole made of two cosmic string universes cannot be supported by a barotropic equation of state. Furthermore, as another side outcome, it was perceived that the radius dependency of the so-called variable equation of state, which is used all over this article, has a great impact on the mechanical stability of the cylindrical asymmetric thin-shell wormholes studied in this brief.