Related papers: Quintom cosmologies admitting either tracking or p…
We review a dynamical dark energy model scarcely studied in the literature and we introduce two possible generalizations. We discuss separately the behavior of the original model and a minimal extension of it by exploring some early and…
The present work deals with the dynamical system investigation of interacting dark energy models (quintessence and phantom) in the framework of Loop Quantum Cosmology by taking into account a broad class of self-interacting scalar field…
We investigate canonical, phantom and quintom models, with the various fields being non-minimally coupled to gravity, in the framework of holographic dark energy. We classify them and we discuss their cosmological implications. In…
In this paper we study the duality in two-field Quintom models of Dark Energy. We find that an expanding universe dominated by Quintom-A field is dual to a contracting universe with Quintom-B field.
We study the dynamics of a phantom scalar field dark energy interacting with dark matter in loop quantum cosmology (LQC). Two kinds of coupling of the form $\alpha{\rho_m}{\dot\phi}$ (case I) and $3\beta H (\rho_\phi +\rho_m)$ (case II)…
We study the phase space of the quintom cosmologies for a class of exponential potentials. We combine normal forms expansions and the center manifold theory in order to describe the dynamics near equilibrium sets. Furthermore, we construct…
In this work we have studied a cosmological model based on a quintom dark energy model non-minimally coupled with gravity, endowed with a specfic potential energy of the exponential squared type. For this specific type of potential energy…
Chameleon dark energy is a matter-coupled scalar field which hides its fifth forces locally by becoming massive. We estimate torsion pendulum constraints on the residual fifth forces due to models with gravitation-strength couplings.…
Two cosmological models with non-phantom matter having the same expansion of the universe as phantom cosmologies are constructed. The first model is characterized by the evolving gravitational "constant" $G$ and a dark energy component with…
The problem of dark energy can be roughly stated as the proposition and validation of a cosmological model that can explain the phenomenon of the accelerated expansion of the Universe. This problem is an open discussion topic in modern…
Dark energy and dark matter are the dominant sources in the evolution of the late universe. They are currently only indirectly detected via their gravitational effects, and there could be a coupling between them without violating…
We investigate a multi-field model of dark energy in this paper. We develop a model of dark energy with two multiple scalar fields, one we consider, is a multifield tachyon and the other is multi-field phantom tachyon scalars. We make an…
Cosmological observations of the recent universe suggest that dark energy equation of state parameter $w$ is growing with time, departing from a cosmological constant for which $w=-1$. Standard quintessence models allow for a varying…
In the present work, we investigate the universe dominated by quintom or hessence energies in Loop Quantum Cosmology (LQC). Interestingly enough, we find that there are some stable attractors in these two cases. In the case of quintom, all…
In this paper I give a brief review on the recently proposed new scenario of dark energy model dubbed $Quintom$. Quintom describes the dynamical dark energy models where the equation of state getting across the cosmological constant…
We study a cosmological model of gravity coupled to three, self-interacting scalar fields, one of them with negative kinetic term. The theory has cosmological solutions described by three-dimensional quadratic autonomous equations, leading…
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…
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…
Cosmological observations allow the possibility that dark energy is caused by phantom fields. These fields typically lead to the occurrence of singularities in the late Universe. We review here the status of phantom singularities and their…
We argue that dark energy with multiple fields is theoretically well-motivated and predicts distinct observational signatures, in particular when cosmic acceleration takes place along a trajectory that is highly non-geodesic in field space.…