Q-balls constructed of spinors in Lagrangians with SU(2) symmetry

TL;DR

This paper explores the existence, stability, and properties of SU(2) spinor q-balls, demonstrating their localized, stable configurations through analytical and numerical methods, including cases with local gauge symmetry.

Contribution

It introduces a new class of SU(2) spinor q-balls, analyzing their stability and properties both analytically and numerically, extending previous scalar field results.

Findings

Stable SU(2) spinor q-balls exist with internal rotation.

Energy and charge are characterized in thin and thick-wall regimes.

Stability is confirmed numerically for local gauge symmetry cases.

Abstract

In the present work we investigate the existence and stability properties of q-balls which consist of a couple of scalar fields, forming an SU(2) doublet in a Lagrangian with a global SU(2) symmetry. We find that these spinors can form a localized and stable field configuration, if they rotate in their internal SU(2) space. We find the energy and charge of the soliton in both thin and thick-wall approximation and we prove its stability against decaying to free particles. We also find the asymptotic forms of the scalar and gauge field and the energy and charge of the configuration when the SU(2) symmetry is local. The only assumption is the smallness of the coupling constant $g$. Using numerical methods we prove the stability of the q-ball in the local case.