Large-scale structure formation in cosmology with classical and tachyonic scalar fields

TL;DR

This paper investigates how classical and tachyonic scalar fields influence large-scale structure formation in cosmology, analyzing perturbations and comparing models with observational data to understand dark energy's role.

Contribution

It introduces a detailed analysis of scalar perturbations in cosmological models with classical and tachyonic scalar fields, reconstructing potentials based on observational parameters.

Findings

Scalar perturbations analyzed at linear and non-linear stages.

Models with constant w do not resolve dark energy degeneracy.

Comparison with observational data highlights limitations in current models.

Abstract

The evolution of scalar perturbations is studied for 2-component (non-relativistic matter and dark energy) cosmological models at the linear and non-linear stages. The dark energy is assumed to be the scalar field with either classical or tachyonic Lagrangian and constant equation-of-state parameter w. The fields and potentials were reconstructed for the set of cosmological parameters derived from observations. The comparison of the calculated within these models and experimental large-scale structure characteristics is made. It is shown that for w=const such analysis can't remove the existing degeneracy of the dark energy models.