Stability of a non-minimally conformally coupled scalar field in F(T) cosmology

TL;DR

This study examines the stability and cosmic evolution of a non-minimally conformally coupled scalar field within F(T) cosmology, revealing the absence of attractor solutions and the potential for phantom energy dominance at late times.

Contribution

It introduces a new scalar field model in F(T) cosmology, analyzing its stability and phase space, and explores its implications for late-time cosmic acceleration and phantom crossing.

Findings

No attractor solutions exist in the model.

Late-time universe dominated by phantom energy.

Phantom crossing is possible in the model.

Abstract

In this paper, we introduce a non-minimally conformally coupled scalar field and dark matter in F(T) cosmology and study their dynamics. We investigate the stability and phase space behavior of the parameters of the scalar field by choosing an exponential potential and cosmologically viable form of F(T). We found that the dynamical system of equations admits two unstable critical points; thus no attractor solutions exist in this cosmology. Furthermore, taking into account the scalar field mimicking quintessence and phantom energy, we discuss the corresponding cosmic evolution for both small and large times. We investigate the cosmological implications of the model via the equation of state and deceleration parameters of our model and show that the late-time Universe will be dominated by phantom energy and, moreover, phantom crossing is possible. Our results do not lead to explicit predictions for inflation and the early Universe era.