Mimicking the cosmological constant: constant curvature spherical solutions in a non-minimally coupled model

TL;DR

This paper demonstrates how non-minimal coupling in a gravitational model can produce constant curvature regions mimicking the cosmological constant, by matching matter distributions with interstellar medium densities.

Contribution

It introduces a novel non-minimal coupling approach to generate constant curvature solutions that replicate the effects of a cosmological constant on large scales.

Findings

Constant curvature regions can be achieved with realistic matter profiles.

The model successfully mimics a large-scale cosmological constant.

Matching conditions at boundaries are physically consistent.

Abstract

The purpose of this study is to describe a perfect fluid matter distribution that leads to a constant curvature region, thanks to the effect of a non-minimal coupling. This distribution exhibits a density profile within the range found in the interstellar medium and an adequate matching of the metric components at its boundary. By identifying this constant curvature with the value of the cosmological constant, and superimposing the spherical distributions arising from different matter sources throughout the universe, one is able to mimic a large-scale homogeneous cosmological constant solution.