Dynamics of Interacting Tachyonic Teleparallel Dark Energy

Ali Banijamali

doi:10.1155/2014/631630

Abstract

We consider a tachyon scalar field which is nonminimally coupled to gravity in the framework of teleparallel gravity. We analyze the phase-space of the model, known as tachyonic teleparallel dark energy, in the presence of an interaction between dark energy and background matter. We find that although there exist some late-time accelerated attractor solutions, there is no scaling attractor. So, unfortunately interacting tachyonic teleparallel dark energy cannot alleviate the coincidence problem.

Highlights

Recent astrophysical observations including Supernova Ia [1, 2], large scale structure [3, 4], the baryon acoustic oscillations [5], and cosmic microwave background radiation [6,7,8,9] have indicated that our universe is experiencing an accelerating phase of expansion.There are two ways to explain the current cosmic expansion
Tachyonic teleparallel dark energy is a generalization of the teleparallel dark energy recently proposed by Geng et al
Such an extension is obtained by replacing a canonical scalar field by a noncanonical scalar field

Summary

Introduction

Recent astrophysical observations including Supernova Ia [1, 2], large scale structure [3, 4], the baryon acoustic oscillations [5], and cosmic microwave background radiation [6,7,8,9] have indicated that our universe is experiencing an accelerating phase of expansion. An equivalent form of classical gravity is the so-called teleparallel gravity, in which, instead of using the torsionless Levi-Civita connection, one uses the curvatureless Weitzenbock one In this theory, the dynamical variables are a set of four tetrad (or vierbein) fields that form the pseudoorthogonal bases for the tangent space at each point of spacetime [66,67,68]. Teleparallel dark energy is a recently proposed scenario in which a nonminimal coupling between quintessence and gravity in the framework of teleparallel gravity was considered [84, 85] This theory has a rich structure and its dynamics.

Teleparallel Gravity

Interacting Tachyonic Teleparallel Dark Energy

Phase-Space Analysis

Conclusion