Related papers: Dark Energy
It has been suggested that the Dark Energy Coincidence Problem could be interpreted as a possible link between the cosmological constant and a massive graviton. We show that by using that link and models for the graviton mass a dark energy…
Some issues of the cosmological constant or dark energy are briefly reviewed. There are an increasing number of observations that constrain the equation of state of dark energy more stringently and favor the time-independent cosmological…
We show that if dark energy evolves in time, its dynamical component could be dominated by a bath of dark radiation. Within current constraints this radiation could have up to $\sim 10^4$ times more energy density than the cosmic microwave…
Recent studies by a number of independent collaborations, have correlated the CMB temperatures measured by the WMAP satellite with different galaxy surveys that trace the matter distribution with light from the whole range of 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 review the problem of dark energy, including a survey of theoretical models and some aspects of numerical studies.
A dark energy with a negative energy density in the past can simultaneously address various cosmological tensions, and if it is to be positive today to drive the observed acceleration of the universe, we show that it should have a pole in…
It is now believed that the universe is composed of a small amount of the normal luminous matter, a substantial amount of matter (Cold Dark Matter: CDM) which is non-luminous and a large amount of smooth energy (Dark Energy: DE). Both CDM…
Two exotic elements have been introduced into the standard cosmological model: non-baryonic dark matter and dark energy. The success in converting a hypothesis into a solid theory depends strongly on whether we are able to solve the…
In this brief review, we examine the theoretical consistency and viability of phantom dark energy. Almost all data sets from cosmological probes are compatible with dark energy of the phantom variety (i.e., equation-of-state parameter…
We find that current Cosmic Microwave Background (CMB) anisotropy data strongly constrain the mean spatial curvature of the Universe to be near zero, or, equivalently, the total energy density to be near critical-as predicted by inflation.…
In this work we review briefly the origin and history of the cosmological constant and its recent reincarnation in the form of the dark energy component of the universe. We also comment on the fundamental problems associated to its…
We review the current status of cosmological parameters, dark energy and large-scale structure, from a theoretical and observational perspective. We first present the basic cosmological parameters and discuss how they are measured with…
Modern astronomical data on galaxy and cosmological scales have revealed powerfully the existence of certain dark sectors of fundamental physics, i.e., existence of particles and fields outside the standard models and inaccessible by…
Two new one-parameter tracking behavior dark energy representations $\omega=\omega_0/(1+z)$ and $\omega=\omega_0 e^{z/(1+z)}/(1+z)$ are used to probe the geometry of the Universe and the property of dark energy. The combined type Ia…
The fact that the energy densities of dark energy and matter are similar currently, known as the coincidence problem, is one of the main unsolved problems of cosmology. We present here a model in which a spatial curvature of the universe…
Investigations on dark energy (DE) are currently inconclusive about its time evolution. Hints of this possibility do however glow now and then in the horizon. Herein we assess the current status of dynamical dark energy (DDE) in the light…
In this article, we review a series of recent theoretical results regarding a conventional approach to the dark energy (DE) concept. This approach is distinguished among others for its simplicity and its physical relevance. By compromising…
A pressureless dark matter component fits well with several cosmological observations. However, there are indications that cold dark matter may encounter challenges in explaining observations at small scales, particularly at galactic…
Dark energy dominates the energy density of our Universe, yet we know very little about its nature and origin. Although strong evidence in support of dark energy is provided by the cosmic microwave background, the relic radiation of the Big…