Related papers: Dark Energy
Recent astrophysical observations, pertaining to either high-redshift supernovae or cosmic microwave background temperature fluctuations, as those measured recently by the WMAP satellite, provide us with data of unprecedented accuracy,…
The concept of an all pervading Aether is age old, and contrary to popular belief, it survived the twentieth century too though with different nuances. Using this concept of a background Quantum Vacuum, the author in 1997 proposed a…
The evolution of dark energy density is a crucial quantity in understanding the nature of dark energy. Often, the quantity is described by the so-called equation of state, that is the ratio of dark energy pressure to its density. In this…
Cosmological dark energy is a natural source of variation of the fine structure constant. Using a model-independent approach we show that once general assumptions about the alpha-varying interactions are made, astronomical probes of its…
A review of the development of the concept of dark matter is given. I begin the review with the description of the discovery of the mass paradox in our Galaxy and in clusters of galaxies. In mid 1970s the amount of observational data was…
We consider the fate of the observable universe in the light of the discovery of a dark energy component to the cosmic energy budget. We extend results for a cosmological constant to a general dark energy component and examine the…
The discovery of accelerated Hubble expansion in the SNIa data and the observed power spectrum of the microwave background radiation provide an ample support for Dark energy and Dark matter. Except for the so far well-known facts that cold…
Recent observations confirm that our universe is flat and consists of a dark energy component $\Omega_{DE}\simeq 0.7$. This dark energy is responsible for the cosmic acceleration as well as determines the feature of future evolution of the…
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…
Several independent cosmological data, collected within the last twenty years, revealed the accelerated expansion rate of the Universe, usually assumed to be driven by the so called dark energy, which, according to recent estimates,…
Modern astrophysical and cosmological models are plagued with two severe theoretical difficulties, namely, the dark energy and the dark matter problems. Relative to the former, high-precision observational data have confirmed with startling…
Progress in observational cosmology over the past five years has established that the Universe is dominated dynamically by dark matter and dark energy. Both these new and apparently independent forms of matter-energy have properties that…
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…
It is shown that quantum vacuum fluctuations give rise to a curvature of space-time of the order appropriate to explain the observed accelerated expansion of the universe. The fact that the fluctuations produce curvature, even if the…
Dark matter represents currently an outstanding problem in both cosmology and particle physics. In this review we discuss the possible explanations for dark matter and the experimental observables which can eventually lead to the discovery…
We outline a dynamical dark energy scenario whose signatures may be simultaneously tested by astronomical observations and laboratory experiments. The dark energy is a field with slightly sub-gravitational couplings to matter, a logarithmic…
In this article we address the mystery of dark matter. We expound the various evidences, astrophysical and cosmological, leading to hypothesize the existence of an invisible form of matter, whose attempts at detecting it have so far all…
We present a new interpretation of dark energy in terms of an \textit{Abnormally Weighting Energy} (AWE). This means that dark energy does not couple to gravitation in the same way as ordinary matter, yielding a violation of the weak and…
Dark energy is the candidate that can produce effective negative pressure and make the galaxies and galaxy clusters move away from each other in an accelerated way. The structures of the Universe have evolved from some initial primordial…
In this work, we quantify the cosmological signatures of dark energy radiation -- a novel description of dark energy, which proposes that the dynamical component of dark energy is comprised of a thermal bath of relativistic particles…