Equation of state and singularities in FLRW cosmological models

TL;DR

This paper explores how different equations of state for dark energy influence the formation of singularities in FLRW cosmological models by developing a perturbative solution relating equation of state coefficients to singularity types.

Contribution

It introduces a general power expansion form of the dark energy equation of state into Friedmann equations and analyzes the resulting singularity formation.

Findings

Perturbative solutions link equation of state coefficients to singularity types.

General power expansion of the equation of state provides insights into singularity formation.

Framework applicable to various dark energy models.

Abstract

We consider FLRW cosmological models with standard Friedmann equations, but leaving free the equation of state. We assume that the dark energy content of the universe is encoded in an equation of state $p=f(\rho)$, which is expressed with most generality in the form of a power expansion. The inclusion of this expansion in Friedmann equations allows us to construct a perturbative solution and to relate the coefficients of the equation of state with the formation of singularities of different types.