Phase-Space analysis of Teleparallel Dark Energy

TL;DR

This paper conducts a comprehensive dynamical analysis of teleparallel dark energy, revealing multiple late-time behaviors including quintessence-like, stiff, and cosmological constant-like solutions, with dark energy equation-of-state flexibility.

Contribution

It introduces a detailed phase-space analysis of teleparallel dark energy, highlighting new late-time solutions and the model's ability to mimic observed dark energy dynamics.

Findings

Universe can evolve to quintessence-like or stiff dark-energy solutions.

An additional late-time solution behaves like a cosmological constant.

Dark energy equation-of-state can be above or below -1.

Abstract

We perform a detailed dynamical analysis of the teleparallel dark energy scenario, which is based on the teleparallel equivalent of General Relativity, in which one adds a canonical scalar field, allowing also for a nonminimal coupling with gravity. We find that the universe can result in the quintessence-like, dark-energy-dominated solution, or to the stiff dark-energy late-time attractor, similarly to standard quintessence. However, teleparallel dark energy possesses an additional late-time solution, in which dark energy behaves like a cosmological constant, independently of the specific values of the model parameters. Finally, during the evolution the dark energy equation-of-state parameter can be either above or below -1, offering a good description for its observed dynamical behavior and its stabilization close to the cosmological-constant value.