Q-ball stress stability criterion in the $U(1)$ gauged scalar theories

TL;DR

This paper investigates the stability of gauged Q-balls in specific scalar field models by analyzing their energy-momentum tensor, revealing conditions under which they remain stable or become destabilized by electrostatic forces.

Contribution

It introduces a stability criterion based on the energy-momentum tensor analysis for gauged Q-balls in two scalar models, highlighting the role of electrostatic repulsion.

Findings

Electrostatic repulsion can destabilize gauged Q-balls.

Gauged Q-balls are stable in the Fridberg-Lee-Sirlin-Maxwell model with a long-range scalar.

Stability depends on the scalar potential and the model parameters.

Abstract

We study the canonical energy-momentum tensor of the spherically symmetric $U(1)$ gauged Q-ball configurations in the two-component Fridberg-Lee-Sirlin-Maxwell model, and in the one-component scalar model with a sixtic potential. We evaluate the distributions of the corresponding shear forces and pressure and study the stability criteria for these solutions. It is shown that the electrostatic repulsion may destabilize the $U(1)$ gauged Q-balls. However, in the limiting case of the Fridberg-Lee-Sirlin-Maxwell model with a long ranged real scalar component, the gauged Q-balls always remain stable.