Related papers: Exploring Parameter Constraints on Quintessential …
Cosmological simulations play a crucial role in elucidating the effect of physical parameters on the statistics of fields and on constraining parameters given information on density fields. We leverage diffusion generative models to address…
We investigate constraints on some key cosmological parameters by confronting metastable dark energy models with different combinations of the most recent cosmological observations. Along with the standard $\Lambda$CDM model, two…
In the present paper, we investigate three scalar fields, \qu field, phantom field and tachyon field, to explore the source of dark energy, using the Gaussian processes method from the background data and perturbation growth rate data. The…
Quintessence scalar fields are a natural candidate for evolving dark energy. Unlike the phenomenological $w_0w_a$ parameterization of the dark energy equation of state, they cannot accommodate the phantom regime of dark energy $w(z) < -1$,…
Our work deals with the dynamical system analysis of quintessence dark energy scalar field model with exponential potential. A dynamical system analysis has been applied at the background level. Using suitable transformation of variables,…
An impressive amount of different astrophysical data converges towards the picture of a spatially flat universe undergoing a today phase of accelerated expansion. The nature of the dark energy dominating the energy content of the universe…
The coupled dark energy models, in which the quintessence scalar field nontrivially couples to the cold dark matter, have been proposed to explain the coincidence problem. In this paper we study the perturbations of coupled dark energy…
The effective field theory (EFT) of dark energy provides a model-independent framework for studying cosmology within scalar-tensor theories. In this work, we explore how the time evolution of the cosmological background, inferred from…
We consider coupled dark energy (CDE) cosmologies, where dark matter particles feel a force stronger than gravity, due to the fifth force mediated by a scalar field which plays the role of dark energy. We perform for the first time a…
We investigate the possibility of a dark energy component that is scaling with epochs. A phenomenological model is introduced whose energy density depends on the redshift in such a way that a smooth transition among the three dominant…
The cosmological history and evolution are examined for gravitational models with interaction in the dark sector of the universe. In particular, we consider the dark energy to be described by a phantom scalar field and the dark matter $\rho…
One fundamental physics interpretation of Dark Energy Spectroscopic Instrument (DESI) results is that the observed accelerated expansion of the Universe is driven not by the cosmological constant, but by a slowly rolling scalar field, a…
The explanation of the accelerated expansion of the Universe poses one of the most fundamental questions in physics and cosmology today. If the acceleration is driven by some form of dark energy, one can try to constrain the parameters…
We consider three cosmological models with linear interaction between the dark components and obtain restrictions on the coupling constant in terms of the cosmographic parameters. It enables us to find constraints on the coupling constant…
We explore an extension of the $\Lambda$CDM model in which the pressure $p$ of the dark energy (DE) fluid evolves with the expansion of the Universe, expressed as a function of the scale factor $a$. The corresponding energy density $\rho$…
The dark energy component of the universe is often interpreted either in terms of a cosmological constant or as a scalar field. A generic feature of the scalar field models is that the equation of state parameter w= P/rho for the dark…
We investigate phantom cosmology in which the scale factor is a power law, and we use cosmological observations from Cosmic Microwave Background (CMB), Baryon Acoustic Oscillations (BAO) and observational Hubble data, in order to impose…
In this paper, we study several models and parameterizations of dynamical dark energy (DE) that have been studied already in the past, in conjunction with the recently proposed model $w$XCDM, the running vacuum model (RVM) with and without…
Reconstructed from lensing tomography, the evolution of the dark matter density field in the well-understood linear regime can provide model-independent constraints on the growth function of structure and the evolution of the dark energy…
Dark energy, the enigmatic force driving the accelerated cosmic expansion of the universe, is conventionally described as a cosmological constant in the standard $\Lambda$CDM model. However, measurements from the Dark Energy Spectroscopic…