Linear stability analysis of a rotating thin-shell wormhole

TL;DR

This paper analyzes the linear stability of a rotating thin-shell wormhole constructed from BTZ spacetimes, revealing that increased angular momentum enhances stability up to a critical point, beyond which stability is maintained regardless of the fluid's equation of state.

Contribution

It introduces a new stability analysis for rotating thin-shell wormholes with a barotropic fluid, highlighting the stabilizing effect of angular momentum beyond a critical value.

Findings

Stability increases with angular momentum until a critical value.

Overcritical rotation leads to a stable wormhole radius independent of fluid properties.

The stability condition changes significantly when angular momentum exceeds the critical threshold.

Abstract

We cut and paste two Banados-Teitelboim-Zanelli (BTZ) spacetimes at a throat by the Darmois-Israel method to construct a rotating wormhole with a thin shell filled with a barotropic fluid. The thin shell at the throat and both sides of the throat corotate. We investigate the linear stability of the thin shell of the rotating wormhole against radial perturbations. We show that the wormhole becomes more and more stable the larger its angular momentum is until the angular momentum reaches a critical value and that the behavior of a condition for stability significantly changes when the angular momentum exceeds the critical value. We find that the overcritical rotating wormhole has the radius of the thin shell, which is stable regardless of the equation of state for the barotropic fluid.