On curvature coupling and quintessence fine-tuning

TL;DR

This paper explores a phenomenological model where quintessence potential energy depends on spatial curvature, proposing a coupling that could explain cosmic acceleration and address fine-tuning issues.

Contribution

It introduces a new curvature-dependent quintessence model with a perfect fluid description, offering a potential solution to the universe's accelerating expansion and fine-tuning problem.

Findings

Scalar field pressure differs with potential dependence

Energy momentum tensor expressed as perfect fluid

Proposes a coupling explaining cosmic acceleration

Abstract

We discuss the phenomenological model in which the potential energy of the quintessence field depends linearly on the energy density of the spatial curvature. We find that the pressure of the scalar field takes a different form when the potential of the scalar field also depends on the scale factor and the energy momentum tensor of the scalar field can be expressed as the form of a perfect fluid. A general coupling was proposed to explain the current accelerating expansion of the Universe and solve the fine-tuning problem.