Hayward Boson Stars

TL;DR

This paper investigates Hayward boson stars within a nonlinear electrodynamics framework, identifying conditions for their existence based on charge and scalar field parameters, and analyzing their solution space.

Contribution

It introduces a new analysis of Hayward boson stars in a nonlinear electrodynamics context, establishing a specific condition for their existence.

Findings

Boson stars exist when rac{\u221a{eta}}{Q}> 1.49661.

Electrovacuum spacetimes without scalar fields contain at least one horizon.

The solution space varies with charge parameter Q and central scalar field value.

Abstract

We examined the Einstein-Klein-Gordon system coupled to a nonlinear electrodynamics framework that asymptotically supports a Hayward spacetime. We explored the solution space of a static spherically symmetric, complex scalar field minimally coupled to the gravitational field known as Hayward Boson stars originally studied by Yue and Wang. We construct families of Hayward boson stars in the ground state, for different values of the charge parameter $Q$, and different values of the central scalar field. One of the main results of our analysis is the fact that the existence of boson stars is guaranteed once the condition $\frac{\sqrt{\beta}}{Q}> 1.49661$, where $\beta$ is a parameter of the electrodynamic theory, is fulfilled. When this condition is not satisfied the electrovacum spacetime contains at least one horizon and the spacetime can not support a scalar field configuration.