Dynamical System Analysis of Interacting Hessence Dark Energy in $f(T)$ Gravity

TL;DR

This paper performs a non-linear dynamical system analysis of Hessence dark energy coupled with dark matter in $f(T)$ gravity, revealing new stable solutions and universe evolutions that differ from linear approaches.

Contribution

It introduces a non-linear dynamical system approach to analyze Hessence dark energy in $f(T)$ gravity, providing novel stable solutions and avoiding Big Rip singularities.

Findings

Universe may evolve like the $ ext{Λ}$CDM model.

All fixed points avoid Big Rip singularity.

Non-linear analysis yields different stable solutions than linear methods.

Abstract

In this work, we have carried on dynamical system analysis of hessence field coupling with dark matter in $f(T)$ gravity. We have analysed the critical points due to autonomous system. The resulting autonomous system is non-linear. So, we have approached via the the theory of non-linear dynamical system.We have noticed very few papers are devoted to this kind of study.Maximum works in literature are done treating the dynamical system as done in linear dynamical analysis, which are unable to predict correct evolution.Our work is totally different from those kind of works.We have used theory of non-linear dynamical system theory,developed till date,in our analysis.This approach gives totally different stable solutions, in contrast what the linear analysis would have predicted. We have discussed the stability analysis in details due to exponential potential through computational method in tabular form and analyzed the evolution of the universe. Some plots are drawn to investigate the behaviour of the system (this plotting technique is different from usual phase plot, and devised by us.). Interestingly, the analysis shows the universe may resemble the `cosmological constant' like evolution (i.e., $\Lambda$CDM model is a subset of the solution set). Also, all the fixed points of our model are able to avoid Big rip singularity.