Latest astronomical constraints on some nonlinear parametric dark energy models

TL;DR

This paper investigates nonlinear, redshift-dependent dark energy models using recent observational data, demonstrating their ability to describe the universe's late-time acceleration and distinguish from the standard Lambda-CDM model.

Contribution

It introduces and constrains nonlinear parametric dark energy models with comprehensive observational data analysis, using CosmoMC for parameter estimation.

Findings

Models can explain late-time cosmic acceleration.

Models are distinguishable from Lambda-CDM.

Constraints are consistent with current observations.

Abstract

We consider nonlinear redshift-dependent equation of state parameters as dark energy models in a spatially flat Friedmann-Lema\^itre-Robertson-Walker universe. To depict the expansion history of the universe in such cosmological scenarios, we take into account the large scale behaviour of such parametric models and fit them using a set of latest observational data with distinct origin that includes cosmic microwave background radiation, Supernove Type Ia, baryon acoustic oscillations, redshift space distortion, weak gravitational lensing, Hubble parameter measurements from cosmic chronometers and finally the local Hubble constant from Hubble space telescope. The fitting technique avails the publicly available code Cosmological Monte Carlo (CosmoMC), to extract the cosmological information out of these parametric dark energy models. From our analysis it follows that those models could describe the late time accelerating phase of the universe, while they are distinguished from the $\Lambda-$cosmology.