Stability of a class of neutral vacuum bubbles

TL;DR

This paper investigates the stability of neutral vacuum bubbles influenced by scalar fields and boson trapping, revealing conditions under which bubbles are short-lived or long-lived based on boson trapping location.

Contribution

It introduces a model with domain wall interactions and analyzes how boson trapping inside or on the wall affects bubble stability, highlighting new stabilization mechanisms.

Findings

Bosons trapped in the wall lead to temporary stabilization.

Bosons trapped inside the bubble can stabilize it if the wall is thin.

Bubble lifetime depends on boson trapping location and wall thickness.

Abstract

A model that gives rise to vacuum bubbles is considered where the domain wall field interacts with another real scalar field, resulting in the formation of domain ribbons within the host domain wall. Ribbon-antiribbon annihilations produce elementary bosons whose mass inside the wall is different from the mass in vacuum. Two cases are considered, where the bosons get trapped either within the bubble wall or the bosons get trapped within the vacuum enclosed by the bubble. The bosonic (meta)stabilization effect on the bubble is examined in each case. It is found that when the bosons become trapped within the bubble wall, the stabilization mechanism lasts for only a limited amount of time, and then the bubble undergoes unchecked collapse. However, when the bosons become trapped within the bubble's interior volume, the bubble can be long-lived, provided that it has a sufficiently thin wall.