Cosmic Dynamics in the Chameleon Cosmology

TL;DR

This paper explores chameleon cosmology in a Friedmann-Robertson-Walker universe, demonstrating its consistency with observations and analyzing its implications for the universe's expansion history through the cosmological redshift drift test.

Contribution

It introduces a chameleon cosmology model that aligns with current observational data and examines its effects on the universe's expansion and redshift evolution.

Findings

The model predicts an EoS parameter evolving from > -1 to < -1.

Cosmological redshift drift measurements support the model.

The model is consistent with current observational constraints.

Abstract

We study in this paper chameleon cosmology applied to Friedmann-Robertson-Walker space, which gives rise to the equation of state (EoS) parameter larger than -1 in the past and less than -1 today, satisfying current observations. We also study cosmological constraints on the model using the time evolution of the cosmological redshift of distant sources which directly probes the expansion history of the universe. Due to the evolution of the universe's expansion rate, the model independent Cosmological Redshift Drift (CRD)test is expected to experience a small, systematic drift as a function of time. The model is supported by the observational data obtained from the test.