Evolution of spherical overdensities in new agegraphic dark energy model

TL;DR

This paper investigates the formation of structures in the universe within the new agegraphic dark energy model, comparing it to other cosmological models and analyzing the evolution of spherical overdensities.

Contribution

It provides a detailed analysis of spherical collapse parameters in the new agegraphic dark energy model and compares these with EdS and b1CDM models, highlighting differences in structure sizes and densities.

Findings

Dark energy dominates at low redshifts, matter at high redshifts.

Structures in the new agegraphic dark energy model are smaller, denser, and larger than in EdS and b1CDM models.

Results are consistent with observations and compared with other dark energy models.

Abstract

We study the structure formation by investigating the spherical collapse model in the context of new agegraphic dark energy model in flat FRW cosmology. We compute the perturbational quantities $g(a)$, $\delta_{c}(z_{c})$, $\lambda(z_{c})$, $\xi(z_{c})$, $\Delta_{vir}(z_{c})$, $\log[\nu f(\nu)]$ and $\log[n(k)]$ for the new agegraphic dark energy model and compare the results with those of EdS and $\Lambda CDM$ models. We find that there is a dark energy dominated universe at low redshifts and a matter dominated universe at high redshifts in agreement with observations. Also, the size of structures, the overdense spherical region, and the halo size in the new agegraphic dark energy model are found smaller, denser, and larger than those of EdS and $\Lambda CDM$ models. We compare our results with the results of tachyon scalar field and holographic dark energy models.