Observational constraints on variable equation of state parameters of dark matter and dark energy after Planck

TL;DR

This study constrains the variable equation of state parameters of dark matter and dark energy using recent observational data, supporting the cold dark matter and cosmological constant model.

Contribution

It provides new observational constraints on the dynamic equation of state parameters for dark matter and dark energy within a flat FRW universe.

Findings

Observational data tightly constrain dark matter's equation of state.

Data favor cold dark matter and cosmological constant dark energy.

Perturbation analysis shows consistency with CMB and matter power spectra.

Abstract

In this paper, we study a cosmological model in general relativity within the framework of spatially flat Friedmann-Robertson-Walker space-time filled with ordinary matter (baryonic), radiation, dark matter and dark energy, where the latter two components are described by Chevallier-Polarski-Linder equation of state parameters. We utilize the observational data sets from SNLS3, BAO and Planck+WMAP9+WiggleZ measurements of matter power spectrum to constrain the model parameters. We find that the current observational data offer tight constraints on the equation of state parameter of dark matter. We consider the perturbations and study the behavior of dark matter by observing its effects on CMB and matter power spectra. We find that the current observational data favor the cold dark matter scenario with the cosmological constant type dark energy at the present epoch.