Oscillating Quintessence

TL;DR

This paper proposes an oscillating scalar field model for dark energy, where the equation of state depends on the potential's power, potentially explaining cosmic acceleration with less fine-tuning.

Contribution

It introduces a novel oscillating quintessence model with a power-law potential, linking the equation of state to the potential's power and analyzing observational constraints.

Findings

Oscillating quintessence can drive cosmic acceleration when 0 < n < 1.

The model relates the equation of state directly to the potential's power n.

A natural model with reduced fine-tuning is proposed.

Abstract

An oscillating scalar field as a quintessence model for dark energy is proposed. The case of a power-law potential is particularly intriguing and is the focus of the present article. In this model the equation of state w_{OQ} of dark energy is a constant determined simply by the power n in the potential through w_{OQ} = (n-2)/(n+2). Accordingly, when 0 < n < 1, the oscillating quintessence can provide repulsive gravity and drive the cosmic acceleration. The condition for oscillation and the constraints from observations are investigated. For this new scenario a specific natural model with much less fine tuning is presented.