Boson stars with nonminimal coupling

TL;DR

This paper explores how nonminimal coupling in boson stars affects their structure, making them more similar to dark energy stars and improving their potential as black hole mimickers.

Contribution

It demonstrates that nonminimal coupling enhances boson stars' compactness and resemblance to dark energy stars, unlike ordinary boson stars.

Findings

Nonminimally coupled boson stars have higher compactness than ordinary ones.

Configurations resemble dark energy stars more closely.

A boson star with a global monopole can mimic black holes effectively.

Abstract

Boson stars coupled to Einstein's general relativity possess some features similar to gravastars, such as the anisotropy in principal pressures and relatively large compactness ($\mu_{max} = 0.32$). However, no matter how large the self-interaction is, the ordinary boson star cannot obtain arbitrarily large compression and as such does not represent a good black hole mimicker. When the boson star is nonminimally coupled to gravity, the resulting configurations resemble more the dark energy stars then the ordinary boson stars, with compactness significantly larger then that in ordinary boson stars (if matter is not constrained with the energy conditions). The gravitationally bound system of a boson star and a global monopole represents a good black hole mimicker.