Related papers: Spherical collapse in coupled quintessence with a …
Growing Neutrino quintessence describes a form of dynamical dark energy that could explain why dark energy dominates the universe only in recent cosmological times. This scenario predicts the formation of large scale neutrino lumps which…
The bulk viscosity of cosmological fluid and the creation of cold dark matter both result in the generation of irreversible entropy (related to dissipative processes) in a homogeneous and isotropic universe. To consider such effects, the…
The DGP (Dvali, Gabadaze and Porrati) braneworld cosmology gives an alternative to dark energy. In DGP cosmology the alleged cosmic acceleration is generated by the modification of gravity theory. Nonlinear evolution of matter density…
We study a quintessence model for which the scalar field is disformally coupled to dark matter. The background mimics the LCDM cosmological evolution and the quintessence potential is not specified. A disformal effect due to the…
In the context of a spatially flat $\Lambda(t)$CDM cosmology, we investigate interacting dark energy (IDE) scenarios characterized by phenomenological interaction terms proportional to the Hubble expansion rate and the dark energy density.…
Spherical collapse predicts that a single value of the turnaround density (average matter density within the scale on which a structure detaches from the Hubble flow) characterizes all cosmic structures at the same redshift. It has been…
We discuss the evolution of linear perturbations in a quintessence model in which the scalar field is non-minimally coupled to cold dark matter. We consider the effects of this coupling on both cosmic microwave background temperature…
The influence of considering a generalized dark matter (GDM) model, which allows for a non-pressure-less dark matter and a non-vanishing sound speed in the non-linear spherical collapse model is discussed for the Einstein-de Sitter-like…
We investigate the creation of cold dark matter (CCDM) cosmology as an alternative to explain the cosmic acceleration. Particular attention is given to the evolution of density perturbations and constraints coming from recent observations.…
We investigate the cosmological evolution of mimetic matter model with arbitrary scalar potential. The cosmological reconstruction, which is the way to construct a model for arbitrary evolutions of the scale factor, is explicitly done for…
We perform numerical evolutions of cosmological scenarios using a standard general relativistic code in spherical symmetry. We concentrate on two different situations: initial matter distributions that are homogeneous and isotropic, and…
We study a coupled quintessence model with pure momentum exchange and present the effects of such an interaction on the Cosmic Microwave Background (CMB) and matter power spectrum. For a wide range of negative values of the coupling…
The collapse barrier, $\delta_{c}$, of the field clusters located in the low-density environment is deterministic rather than diffusive, unlike that of the wall counterparts located in the superclusters. Analyzing the data from the…
We use the spherical collapse model of structure formation to investigate the separation in the collapse of uncoupled matter (essentially baryons) and coupled dark matter in an interacting dark energy scenario. Following the usual…
In the Cold Dark Matter (hereafter CDM) scenario even isolated density peaks contain a high fraction of small scale clumps having velocities larger than the average escape velocity from the structure. These clumps populate protoclusters,…
We investigate an interacting dark energy model which allows for the kinetic term of the scalar field to couple to dark matter via a power-law interaction. The model is characterised by scaling solutions at early times, which are of high…
Based on flat Friedmann-Robertson Walker cold dark matter (CDM) type models driven by non-relativistic matter and an exotic fluid (quintessence) with an equation of state: $p_{Q}=w\rho_{Q}$ ($-1\le w<0$), we investigate whether or not the…
We use the spherical collapse model to demonstrate that the observable average density of virialized clusters depends on the properties of dark energy along with the properties of gravity on cluster scales and can therefore be used as a…
We have analyzed the dependences of the threshold value of amplitude of linear density fluctuation collapsed at the current epoch, $\delta_c$, and its overdensity after virialization, $\Delta_c$, on matter density content, 3D curvature…
Many models have been studied that contain more than one species of dark matter and some of these couple the Cold Dark Matter (CDM) to a light scalar field. In doing this we introduce additional long range forces, which in turn can…