Stability Analysis in Tachyonic Potential Chameleon cosmology

TL;DR

This paper analyzes the stability and cosmological implications of a tachyonic potential chameleon scalar-field model, identifying attractors, fixed points, and phantom crossing behavior, and constrains model parameters using observational data.

Contribution

It provides an analytic approach to fixed points and stability in the model, and fits the model parameters to recent observational data.

Findings

Identification of stable attractors and fixed points.

Prediction of phantom crossing in the equation of state.

Model parameters constrained by supernovae and redshift drift data.

Abstract

We study general properties of attractors for tachyonic potential chameleon scalar-field model which possess cosmological scaling solutions. An analytic formulation is given to obtain fixed points with a discussion on their stability. The model predicts a dynamical equation of state parameter with phantom crossing behavior for an accelerating universe. We constrain the parameters of the model by best fitting with the recent data-sets from supernovae and simulated data points for redshift drift experiment generated by Monte Carlo simulations.