Related papers: Dynamical Mutation of Dark Energy
Since the discovery of the accelerated expansion of the Universe, the constraints on the equation of state $w_\text{DE}$ of dark energy, the stress-energy component responsible for the acceleration, have tightened significantly. These…
Topics concerning dark energy and the accelerating expansion of universe are briefly reported. Arguments about the quantum fluctuations of vacuum are examined in order to decide if the Casimir force really is a laboratory evidence of dark…
It is argued that fluctuations of quantum fields in four-dimensional space do not give rise to dark energy, but are rather a negligible contribution to dark matter. By (relativistic) dark matter we mean that the relation between pressure…
In a four dimensional manifold formalism we study the evolutionary behavior as well as the ultimate fate of the universe, in the course of which the contribution of dark energy in these phases are investigated. At one stage we get a…
There is compelling evidence that the Universe is undergoing a late phase of accelerated expansion. One of the simplest explanations for this behaviour is the presence of dark energy. A plethora of microphysical models for dark energy have…
We study the behavior of metric perturbations in a recently proposed model of phantom dark energy with tachyonic instability at long wavelengths. We find that metric perturbations exponentially grow in time, starting from very small values…
The energy content of the vacuum condensate induced by the neutrino mixing is interpreted as dynamically evolving dark energy.
We investigate how the nature of dark energy affects the determination of the curvature of the universe from recent observations. For this purpose, we consider the constraints on the matter and dark energy density using observations of type…
We investigate the clustering properties of dynamical Dark Energy even in association of a possible coupling between Dark Energy and Dark Matter. We find that within matter inhomogeneities, Dark Energy migth form voids as well as…
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…
The equation of state of dark energy is investigated to determine how much it may deviate from the equation of state of the cosmological constant (CC). Two aspects of the problem are studied: the "expansion" around the vacuum equation of…
I consider some of the issues we face in trying to understand dark energy. Huge fluctuations in the unknown dark energy equation of state can be hidden in distance data, so I argue that model-independent tests which signal if the…
The exact solution for dynamic of conform-flat space homogeneous since dynamic equation is given. Conform mode of space metric changing in Global time theory has negative energy density. Swap of energy to this mode from another ones lead to…
We perform a full dynamical analysis by considering the interactions between dark energy and radiation, and dark energy and dark matter. We find that the interaction helps alleviate the coincidence problem for the quintessence model.
Acceleration of the universe might be driven by a continuous elastic medium -- elastic dark energy (Bucher and Spergel 1999). Elastic dark energy can stably support equations of state with pressure to energy ratio w > -4/3. Stable expansion…
We extract key information of dark energy from current observations of BAO, OHD and $H_0$, and find hints of dynamical behaviour of dark energy. In particular, a dynamical dark energy model whose equation of state crosses $-1$ is favoured…
Evolution of cosmological perturbations is considered in the model with dynamical dark energy which non-gravitationally interacts with dark matter. The dark energy equation of state parameter (EoS) is varying in time and is parameterized by…
An interaction between dark matter and dark energy is usually introduced by a phenomenological modification of the matter conservation equations, while the Einstein equations are left unchanged. Starting from some general and fundamental…
It is argued that dark energy -or something dynamically equivalent at the background level- is necessary if the expanding universe is to behave as an ordinary macroscopic system; that is, if it is to tend to some thermodynamic equilibrium…
We analyze the interaction between Dark Energy and Dark Matter from a thermodynamical perspective. By assuming they have different temperatures, we study the possibility of occurring a decay from Dark Matter into Dark Energy, characterized…