Studies of no light scalar hair behaviors for compact reflecting stars in a box

TL;DR

This paper investigates the conditions under which scalar fields can or cannot form hair around compact reflecting stars in a box, revealing that charge can enable scalar hair formation contrary to neutral cases.

Contribution

It introduces the concept of no light scalar hair behaviors for neutral stars and demonstrates how charge can violate this property in scalar field configurations.

Findings

Neutral compact stars cannot support small scalar fields outside.

Adding charge allows scalar hair formation.

The no light scalar hair property can be broken by electromagnetic coupling.

Abstract

We study condensation of scalar fields around compact reflecting stars in a box. We propose no light scalar hair behaviors that the neutral compact star cannot support the existence of small single positive mass scalar field in it's exterior spacetime for very general self-interacting potentials. Moreover, we find that this no light scalar hair property can be violated by including an additional Maxwell field coupled to the scalar field in a charged compact reflecting star background.