相关论文: Cosmological dark energy from the cosmic QCD phase…
Astrophysical observations are pointing out huge amounts of dark matter and dark energy needed to explain the observed large scale structures and cosmic accelerating expansion. Up to now, no experimental evidence has been found, at…
The most studied way to explain the current accelerated expansion of the universe is to assume the existence of dark energy; a new component that fill the universe, does not clumps, currently dominates the evolution, and has a negative…
The discovery ten years ago that the expansion of the Universe is accelerating put in place the present cosmological model, in which the Universe is composed of 4% baryons, 20% dark matter, and 76% dark energy. Yet the underlying cause of…
The consideration of dark energy's quanta, required also by thermodynamics, introduces its chemical potential into the cosmological equations. Isolating its main contribution, we obtain solutions with dark energy decaying to matter or…
Here, creation of the universe is obtained only from gravity sector. The dynamical universe begins with two basic ingredients (i) vacuum energy, also called dark energy (as vacuum energy is not observed) and (ii) background radiation. These…
It has been recently argued \cite{Barvinsky:2017lfl} that the de Sitter phase in cosmology might be naturally generated as a result of dynamics of the topologically nontrivial sectors in a strongly coupled QCD-like gauge theory in expanding…
We suggest that the current acceleration of the universe may be explained by the vacuum energy of a hidden sector which is stuck in a state of equilibrium between phases. The phases are associated to a late-time first-order phase…
Dark energy (DE) is not necessarily uniform when other sources of gravity are present: interaction with matter leads to its variation in space and time. We study cosmological implications of this fact by analyzing cosmological models in…
Cosmological models involving an interaction between dark matter and dark energy have been proposed in order to solve the so-called coincidence problem. Different forms of coupling have been studied, but there have been claims that…
In this study, cosmological models are considered, where dark matter and dark energy are coupled and may exchange energy through non-gravitational interactions with one other. These interacting dark energy (IDE) models have previously been…
We explore the possibility of having a composite (self-conserved) dark energy (DE) whose dynamics is controlled by the quantum running of the cosmological parameters. We find that within this scenario it is feasible to find an explanation…
The consideration of dark energy's quanta, required also by thermodynamics, introduces its chemical potential into the cosmological equations. Isolating its main contribution, we obtain solutions with dark energy decaying to matter or…
The recently observed accelerated expansion of the universe has put a challenge for its theoretical understanding. As a possible explanation of this, it is considered that the most part of the present universe is filled with a form of…
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…
Accelerated expansion of the Universe may result from an anti-frictional force that is self-consistently exerted on cold dark matter (CDM). Cosmic anti-friction is shown to give rise to an effective negative pressure of the cosmic medium.…
I briefly review our current understanding of dark matter and dark energy. The first part of this paper focusses on issues pertaining to dark matter including observational evidence for its existence, current constraints and the `abundance…
Many candidate models for dark energy are based on the existence of a classical scalar field. In the context of Quantum Field Theory (QFT), we briefly discus the condensation of such a field from a light quantum scalar field produced by…
Dark energy appears to be the dominant component of the physical Universe, yet there is no persuasive theoretical explanation for its existence or magnitude. The acceleration of the Universe is, along with dark matter, the observed…
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…
An initial state for the observable universe consisting of a finite region with a large vacuum energy will break-up due to near horizon quantum critical fluctuations. This will lead to a Friedmann-like early universe consisting of an…