Related papers: Observational constraints on the generalized $\alp…
We study some cosmological constraints on the two phenomenological models of oscillating dark energy. In these scenarios, the equation of state of dark energy varies periodically and may provide a way to unify the early acceleration…
For two types of quintessence models having thawing and tracking properties, there exist analytic solutions for the dark energy equation of state w expressed in terms of several free parameters. We put observational bounds on the parameters…
Understanding the late-time acceleration of the Universe is one of the major challenges in cosmology today. In this paper, we present a new scalar field model corresponding to a generalised axion-like potential. In fact, this model can be…
The $\alpha$-attractor inflationary models are nowadays favored by CMB Planck observations. Their similarity with canonical quintessence models motivates the exploration of a common framework that explains both inflation and dark energy. We…
We study a known class of scalar dark energy models in which the potential is of exponential type and the current accelerating era is transient. We find that, although a decelerating era will return in future, however, when extrapolating…
We perform a Bayesian study of a generalization of the basic $\alpha$-attractor T model given by the potential $V(\phi)=V_0\left[1-\text{sech}^{p}\left(\phi/\sqrt{6\alpha}M_{pl}\right)\right]$ where $\phi$ is the inflaton field and the…
In this paper we perform a global analysis of the constraints on the inflationary parameters in the presence of dynamical dark energy models from the current observations, including the three-year Wilkinson Microwave Anisotropy Probe…
We present a unified framework for the study of late time cosmic acceleration. Using methods of effective field theory, we show that existing proposals for late time acceleration can be subsumed in a single framework, rather than many…
Cosmological models with Lagrange multipliers are appealing because they could explain the behaviour of the dark sector in a unified way. In this work we analyse extensions to the "Dust of Dark Energy model" proposed in arXiv:1003.5751 by…
We study the cosmological consequences of a class of Dirac-Born-Infeld models, and assess their viability as a candidate for the recent acceleration of the Universe. The model includes both the rolling tachyon field and the generalized…
The recent GW170817 measurement favors the simplest dark energy models, such as a single scalar field. Quintessence models can be classified in two classes, freezing and thawing, depending on whether the equation of state decreases towards…
Dark Energy models with slowly-rolling cosmological scalar field provide a popular alternative to the standard, time-independent cosmological constant model. We study simultaneous evolution of background expansion and growth in the scalar…
We place observational constraints on models with the late-time cosmic acceleration based on a number of parametrizations allowing fast transitions for the equation of state of dark energy. In addition to the model of Linder and Huterer…
The recent observations support that our universe is flat and expanding with acceleration. A quintessence model with a general relation between the quintessence potential and the quintessence kinetic energy was proposed to explain the…
We study general properties of attractors for scalar-field dark energy scenarios which possess cosmological scaling solutions. In all such models there exists a scalar-field dominant solution with an energy fraction \Omega_{\phi}=1 together…
Recently, attempts have been made to understand the apparent near coincidence of the present dark energy and matter energy in terms of a dynamical attractor-like solution for the evolution of a scalar field. In these models the field…
We study quintessential inflation using a generalized exponential potential $V(\phi)\propto exp(-\lambda \phi^n/Mpl^n), n>1$, the model admits slow-roll inflation at early times and leads to close-to-scaling behaviour in the post…
This study explores the dynamics and phase-space behavior of a multi-component dark energy model, where the dark sector consists of a minimally coupled canonical scalar field and the cosmological constant, using a dynamical system analysis…
In this paper, we have proposed a generalized parametrization for the deceleration parameter $q$ in order to study the evolutionary history of the universe. We have shown that the proposed model can reproduce three well known…
The constraints on a general form of the power-law potential and the dissipation coefficient in the framework of warm single field inflation imposed by Planck data will be investigated. {By Considering a quasi-static Universe, besides a…