Tachyonic Teleparallel Dark Energy in Phase Space

Behnaz Fazlpour,Ali Banijamali

doi:10.1155/2013/279768

Behnaz Fazlpour, Ali Banijamali

Open Access

https://doi.org/10.1155/2013/279768

Copy DOI

Abstract

Recently, nonminimal coupling between a noncanonical scalar field and gravity in the framework of teleparallelism has been proposed. Noncanonical scalar field is tachyon field, and the model is known as tachyonic teleparallel dark energy. Here, we perform a dynamical analysis of the model, find its critical points, and study their stability. We find that all the critical points are dark energy dominated solutions corresponding to an accelerating universe. It is also shown that there exist two critical lines which are stable attractors of the model.

Highlights

Recent accelerated expansion of our universe is one of the most significant cosmological discoveries over the last decade [1,2,3,4,5,6]
The authors have found that this scenario possesses a late time attractor in which dark energy behaves like a cosmological constant independently of the specific values of the model parameter, and so this feature provides a natural way for the stabilization of the dark energy equation of state parameter to the cosmological constant value, without the need for parameter tuning
Teleparallel dark energy possesses an additional late-time solution, in which dark energy behaves like a cosmological constant

Summary

Introduction

Recent accelerated expansion of our universe is one of the most significant cosmological discoveries over the last decade [1,2,3,4,5,6]. Using the teleparallel equivalent of general relativity as the gravitational sector, recently Geng et al have proposed teleparallel dark energy by adding a canonical scalar field, allowing for a nonminimal coupling with gravity [37, 38]. They have used the quintessence scalar field as being responsible for dark energy. Teleparallel dark energy scenario in the minimal case is completely equivalent with standard quintessence, it shows interesting cosmological behavior in the nonminimal case.

The Model

Phase Space Analysis

Conclusion