Related papers: Decaying vacuum energy, matter creation and cosmic…
In this paper, after reconstructing the redshift evolution of the Hubble function by adopting Gaussian process techniques, we estimate the best-fit parameters for some flat Friedmann cosmological models based on a Modified Chaplygin Gas…
If dark energy interacts with dark matter, there is a change in the background evolution of the universe, since the dark matter density no longer evolves as a^{-3}. In addition, the non-gravitational interaction affects the growth of…
We examine the growth of structure in three different cosmological models with interacting dark matter and vacuum energy. We consider the case of geodesic dark matter with zero sound speed, where the relativistic growing mode in…
We determine the Hubble expansion and the general cosmic perturbations equations for a general system consisting of self-conserved matter and self-conserved dark energy (DE). While at the background level the two components are…
We examine a cosmological scenario where dark matter is coupled to a variable vacuum energy while baryons and photons are two decoupled components for a spatially flat Friedmann-Robertson-Walker spacetime. We apply the $\chi^{2}$ method to…
Decaying dark matter models provide a physically motivated way of channeling energy between the matter and radiation sectors. In principle, this could affect the predicted value of the Hubble constant in such a way as to accommodate the…
The cosmic expansion is computed for various dynamical vacuum models $\Lambda(H)$ and confronted to the Cosmic Microwave Background (CMB) power spectrum from Planck. We also combined CMB in a joint analysis with other probes in order to…
In this work we explore the scope of two holographic dark energy models within the interacting scenario for the dark sector and spatial curvature. For one holographic model we consider the usual formula for the dark energy density with the…
This paper investigates the effects of spatial curvature in a model where dark matter and dark energy interact. The analysis employs a range of datasets, including CMB, BAO, Type Ia Supernova, $H(z)$ from cosmic chronometers, $H_0$…
We examine interactions between dark matter and dark energy in light of the latest cosmological observations, focusing on a specific model with coupling proportional to the dark energy density. Our data includes Cosmic Microwave Background…
We analyze two different scenarios for the late Universe dynamics, resulting into Hubble parameters deviating from the $\Lambda$CDM, mainly for the presence of an additional free parameter, which is the dark energy parameter. The first…
We present a Bayesian comparative analysis of five cosmological models: $\Lambda$CDM, $w$CDM, $w_0w_a$CDM, $\phi$CDM (with scalar-field dark energy), and an interacting dark energy scenario (the $\xi$-index model), to investigate dark…
In this study, we employ a two-step method to analyze models of holographic dark energy (HDE) and interacting holographic dark energy (IHDE), incorporating three distinct dark energy (DE)-dark matter (DM) interaction terms. First, using the…
In this paper, a well-motivated parametrization of the Hubble parameter ($H$% ) is revisited that renders two models of dark energy showing some intriguing features of the late-time accelerating Universe. A general quintessence field is…
We propose that dark matter (DM) possesses a quadratic equation of state, which becomes significant at high densities, altering the Universe's evolution during its early stages. We derive the modified background evolution equations for the…
We investigate the cosmological dynamics of interacting dark energy within the framework of $\alpha$-attractor models. Specifically, we analyze the associated autonomous system, focusing on its fixed points that represent dark energy and…
In this work we perform an analysis on the recently proposed conjoined cosmic growth and cosmic expansion diagram [1] to compare several dark energy models using the Figure of Merit showed in [2], which consists in the inverse of the…
The coupling between dark sectors provides a possible approach to mitigate the coincidence problem of cosmological standard model. In this paper, dark energy is treated as a fluid with a constant equation of state, whose coupling with dark…
The objective of the present work is to study a cosmological model for a spatially flat Universe whose constituents are a dark energy field and a matter field which includes baryons and dark matter. The constituents are supposed to be in…
In this study, we explore the impact of the interacting parameter on dark matter in a model resulting from a parametrization of dark energy density. To ensure a model-independent approach, we treat \( r_d \) as a free parameter, avoiding…