Field Flows of Dark Energy

TL;DR

This paper analyzes the dynamics of scalar field dark energy during matter domination, introducing a field expansion approach that captures key behaviors beyond slow-roll approximations, applicable to various models.

Contribution

It presents a novel field expansion method to accurately describe dark energy evolution during matter domination, unifying different models and behaviors.

Findings

Field expansion captures dark energy dynamics beyond slow-roll.

The approach applies to thawing, freezing, and modified gravity models.

Provides a unified framework for various dark energy scenarios.

Abstract

Scalar field dark energy evolving from a long radiation- or matter-dominated epoch has characteristic dynamics. While slow-roll approximations are invalid, a well defined field expansion captures the key aspects of the dark energy evolution during much of the matter-dominated epoch. Since this behavior is determined, it is not faithfully represented if priors for dynamical quantities are chosen at random. We demonstrate these features for both thawing and freezing fields, and for some modified gravity models, and unify several special cases in the literature.