General features of single-scalar field dark energy models

TL;DR

This paper systematically analyzes single-scalar field dark energy models within modified gravity frameworks, using effective field theory to derive generic predictions about large scale structures under physical constraints.

Contribution

It introduces a comprehensive approach combining EFT of DE with stability and causality constraints to characterize generic features of scalar-tensor dark energy models.

Findings

Derives generic predictions for large scale structures in scalar-tensor models

Identifies parameter space regions consistent with stability and subluminal propagation

Provides a framework for constraining dark energy models with observational data

Abstract

We present a systematic study of modified gravity (MG) models containing a single scalar field non-minimally coupled to the metric. Despite a large parameter space, exploiting the effective field theory of dark energy (EFT of DE) formulation and imposing simple physical constraints such as stability conditions and (sub-)luminal propagation of perturbations, we arrive at a number of generic predictions about the large scale structures.