相关论文: More on Emergent Dark Energy from Unparticles

General Relativistic Entropic Acceleration (GREA) theory provides a covariant formalism for out-of-equilibrium phenomena in GR, extending the Einstein equations with an entropic force that behaves like bulk viscosity with a negative…

We review the notion of holographic dark energy and assess its significance in the light of the well documented cosmic acceleration at the present time. We next propose a model of holographic dark energy in which the infrared cutoff is set…

Assuming the universe is spatially homogeneous on the largest scales lays the foundation for almost all cosmology. This idea is based on the Copernican principle, that we are not at a particularly special place in the universe.…

We investigate the possibility of replacing the cosmological constant with gradual condensation of a scalar field produced during the decay of a superheavy dark matter. The advantage of this class of models to the ordinary quintessence is…

One of the unresolved questions currently in cosmology is that of the non-linear accelerated expansion of the universe. This has been attributed to the so called Dark Energy (DE). The accelerated expansion of the universe is deduced from…

The idea of a negative-pressure dark energy component in the Universe which causes an accelerated expansion in the late Universe has deep implications in models of field theory and general relativity. In this article, we survey the evidence…

There is mounting observational evidence that the expansion of our Universe is undergoing a late-time acceleration. Among many proposals to describe this phenomenon, the cosmological constant seems to be the simplest and the most natural…

Associated with the cosmic acceleration are the old and new cosmological constant problems, recently put into the more general context of the dark energy problem. In broad terms, the old problem is related to an unexpected order of…

The Hubble expansion of galaxies, the $2.73\dK$ blackbody radiation background and the cosmic abundances of the light elements argue for a hot, dense origin of the universe --- the standard Big Bang cosmology --- and enable its evolution to…

We propose a model of the Universe based on Minkowski flat space-time metric. In this model the space-time does not evolve. Instead the matter evolves such that all the mass parameters increase with time. We construct a model based on…

An overview is presented of a recently proposed "radically conservative" solution to the problem of dark energy in cosmology. The proposal yields a model universe which appears to be quantitatively viable, in terms of its fit to supernovae…

We study some cosmological constraints on the two phenomenological models of oscillating dark energy. In these scenarios, the equation of state of dark energy varies periodically and may provide a way to unify the early acceleration…

Given a class of dark energy models, constraints from one set of cosmic acceleration observables make predictions for other observables. Here we present the allowed ranges for the expansion rate H(z), distances D(z), and the linear growth…

Full suite of the present day Cosmic Microwave background (CMB) data, when combined with weak prior information on the Hubble constant and the age of the Universe, or the Large-Scale structure, provides strong indication for a non-zero…

The present work deals with a cosmological model having particle creation mechanism in the framework of irreversible thermodynamics. In the second order non-equilibrium thermodynamical prescription, the particle creation rate is treated as…

We investigate the effects of viscosity terms depending on the Hubble parameter and its derivatives in the dark energy equation of state. Such terms are possible if dark energy is a fictitious fluid originating from corrections to the…

The accelerated expansion of the Universe is impressively well described by a cosmological constant. However, the observed value of the cosmological constant is much smaller than expected based on quantum field theories. Recent efforts to…

The origin of accelerating expansion of the Universe is one the biggest conundrum of fundamental physics. In this paper we review vacuum energy issues as the origin of accelerating expansion - generally called dark energy - and give an…

A wide range of large scale observations hint towards possible modifications on the standard cosmological model which is based on a homogeneous and isotropic universe with a small cosmological constant and matter. These observations, also…

Major observational efforts in the coming decade are designed to probe the equation of state of dark energy. Measuring a deviation of the equation-of-state parameter w from -1 would indicate a dark energy that cannot be represented solely…