Related papers: The Genesis of Cosmological Tracker Fields
In this work we explore a model of the universe in which dark energy is modelled explicitely with both a dynamical quintessence field (with a double exponential self-interaction potential) and a cosmological constant. For a given region of…
We study the cosmological dynamics of dark energy in a scalar-vector-torsion theory. The vector field is described by the cosmic triad and the scalar field is of the quintessence type with non-minimal coupling to gravity. The coupling to…
We study the entropic considerations on the Universe system and the Universe-Black hole system, filled by cosmological constant or exotic quintessence-like and phantom-like fields having negative pressure, using their relevant entropic…
At present we know nothing about the nature of the dark energy accounting for about 70% of the energy density of the Universe. One possibility is that the dark energy is provided by an extremely light field, the quintessence, rolling down…
When recent observational evidence and the GR+FRW+CDM model are combined we obtain the result that the Universe is accelerating, where the acceleration is due to some not-yet-understood "dark sector". There has been a considerable number of…
We present cosmological perturbation theory in neutrino probe interacting dark-energy models, and calculate cosmic microwave background anisotropies and matter power spectrum. In these models, the evolution of the mass of neutrinos is…
Models in which dark energy interacts with dark matter have been proposed in the literature to help explain why dark energy should only come to dominate in recent times. In this paper, we present a dynamical framework to calculate…
One of the great endeavors of the past decade has been the evaluation of different observational techniques for measuring dark energy properties and of theoretical techniques for constraining models of cosmic acceleration given cosmological…
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…
We perform a comprehensive study of a class of dark energy models - scalar field models where the effective potential can be described by a polynomial series - exploring their dynamical behavior using the method of flow equations that has…
We study a coupled quintessence model in which the interaction with the dark matter sector is a function of the quintessence potential. Such a coupling can arise from a field dependent mass term for the dark matter field. The dynamical…
We derive a condition for converging a common evolutionary track for k-essence (a scalar field dark energy with non-canonical kinetic terms). For the Lagrangian density V(phi)W(X) with X=dot{phi}^2/2, we find tracker solutions with w_{phi}…
We study the interacting quintessence model with two different types of interaction by introducing a general parameterization of the quintessence potentials. The form of the quintessence potentials is arbitrary as the recent cosmological…
Recently proposed theories based on the cosmic presence of a vectorial field are compared and contrasted. In particular the so called Einstein aether theory is discussed in parallel with a recent proposal of a strained space-time theory…
In the Einstein-Cartan gravitational theory with the chameleon field, changing its mass in dependence of a density of its environment, we analyze the Friedmann-Einstein equations for the Universe evolution with the expansion parameter $a$…
This review considers the theoretical approaches to the understanding of dark energy which comprises approximately 68\% of the energy of our Universe and explains an acceleration in its expansion. Following a discussion of the main approach…
Positivity bounds - constraints on any low-energy effective field theory imposed by the fundamental axioms of unitarity, causality and locality in the UV - have recently been used to constrain scalar-tensor theories of dark energy. However,…
In the context of the induced matter theory of gravity, we investigate the possibility of deriving a 4D quintessential scenario where an interaction between dark energy and dark matter is allowed, and the dark energy component is modeled by…
The two most popular candidates for dark energy, i.e. a cosmological constant and quintessence, are very difficult to distinguish observationally, mostly because the quintessence field does not have sizable fluctuations. We study a scalar…
The late time acceleration of the Universe can be characterized in terms of an extra, time dependent, component of the universe -- dark energy. The simplest proposal for dark energy is a scalar-tensor theory -- quintessence -- which…