Growth of perturbations using Lambert W equation of state

Abstract

Recently, a novel equation of state (EoS) parameter for dark energy has been introduced which deals with a special mathematical function, known as the Lambert [Formula: see text] function. In this paper, we study the effect on the growth of perturbations for the Lambert [Formula: see text] dark energy model. We perform the analysis for two different approaches. In the first case, we consider the universe to be filled with two different fluid components, namely, the baryonic matter component and the Lambert [Formula: see text] dark energy component, while in the second case, we consider that there is a single fluid component in the universe whose equation of state parameter is described by the Lambert [Formula: see text] function. We then compare the growth rates of Lambert [Formula: see text] model with that for a standard [Formula: see text]CDM model as well as the CPL model. Our results indicate that the presence of Lambert [Formula: see text] dynamical dark energy sector changes the growth rate and affects the matter fluctuations in the universe to a great extent.