Related papers: Dark Energy: back to Newton?
The discovery of dark energy (DE) as the physical cause for the accelerated expansion of the Universe is the most remarkable experimental finding of modern cosmology. However, it leads to insurmountable theoretical difficulties from the…
Dark energy is one of the greatest scientific mysteries of today. The idea that dark energy originates from quantum vacuum fluctuations has circulated since the late '60s, but theoretical estimations of vacuum energy have disagreed with 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…
Though the concept of a dark energy driven accelerating universe was introduced by the author in 1997, to date dark energy itself, as described below has remained a paradigm. A model for the cosmological constant is suggested.
Nearly seventy per cent of the energy density in the universe is unclustered and exerts negative pressure. This conclusion -- now supported by numerous observations -- poses the greatest challenge for theoretical physics today. I discuss…
The observed cosmic acceleration was attributed to an exotic dark energy in the framework of classical general relativity. The dark energy behaves very similar with vacuum energy in quantum mechanics. However, once the quantum effects are…
We consider the effect of inhomogeneities on the expansion of the Einstein-de Sitter universe. We find that the backreaction of linear scalar metric perturbations results in apparent dark energy with a mixture of equations of state between…
We study the bending of light for static spherically symmetric (SSS) space-times which include a dark energy contribution. Geometric dark energy models generically predict a correction to the Einstein angle written in terms of the distance…
We discuss the possibility that the existence of dark energy may be due to the presence of a spin zero field $\phi(x)$, either elementary or composite. In the presence of other matter field, the transformation $\phi(x)\to \phi(x) +$…
We consider a model where both dark energy and dark matter originate from the coupling of a scalar field with a non-conventional kinetic term to, both, a metric measure and a non-metric measure. An interacting dark energy/dark matter…
In this paper we review a part of the approaches that have been considered to explain the extraordinary discovery of the late time acceleration of the Universe. We discuss the arguments that have led physicists and astronomers to accept…
The discovery of accelerated cosmic expansion implies that, in addition to the attractive gravity of matter, there exists in our universe some other form of energy (dark energy or cosmological constant) producing a repulsive force. The…
The problem of dark energy arises due to its self-gravitating properties. Therefore explaining vacuum energy may become a question for the realm of quantum gravity, that can be addressed within string theory context. In this talk I…
A cosmological constant, Lambda, is the most natural candidate to explain the origin of the dark energy (DE) component in the Universe. However, due to experimental evidence that the equation of state (EOS) of the DE could be evolving with…
Phenomena currently attributed to Dark Energy (DE) and Dark Matter (DM) are merely a result of the interplay between gravitational energy density, generated by the contraction of space by matter, and the energy density of the Cosmological…
We study physics concerning the cosmological constant problem in the framework of effective field theory and suggest that a dominant part of dark energy can originate from gravitational corrections of vacuum energy, under the assumption…
The question of where the inertial properties of matter come from has been open for a long time. Isaac Newton considered inertia an intrinsic property of matter. Ernst Mach held a different view whereby the inertia of a body comes from its…
In this letter, dark energy is obtained using dual roles of the Ricci scalar (as a physical field as well as geometry). Dark energy density, obtained here, mimics phantom and the derived Friedmann equation contains a term $\rho^2_{\rm de}/2…
In this paper we present a possible origin of dark matter and dark energy from a solution of the Einstein's equation to a primordial universe, which was presented in a previous paper. We also analyze the Dirac's equation in this primordial…
Among the great mysteries that physics has not yet solved are undoubtedly those of dark energy and dark matter. In this chapter we deal with the first of them. We will expound in detail the motivations that led to hypothesise the existence…