Related papers: Cosmic ray threshold in an asymptotically dS space…
Direct techniques for cosmic ray observations have reached an unprecedented level of precision, unveiling fine-details of the energy spectra. I will introduce the evidence for new spectral features which has been accumulated by new…
If quantum fields exist in extra compact dimensions, they will give rise to a quantum vacuum or Casimir energy. That vacuum energy will manifest itself as a cosmological constant. The fact that supernova and cosmic microwave background data…
Important observational results have been recently reported on the angular distributions of cosmic rays at all energies, calling into question the perception of cosmic rays a decade ago. These results together with their in-progress…
The accelerating expansion of the Universe points to a small positive value for the cosmological constant or vacuum energy density. We discuss recent ideas that the cosmological constant plus LHC results might hint at critical phenomena…
By exploring the relationship between the propagation of electromagnetic waves in a gravitational field and the light propagation in a refractive medium, it is shown that, in the presence of a positive cosmological constant, the velocity of…
The expression of a time-dependent cosmological constant $\lambda \propto 1/t^2$ is interpreted as the energy density of a special type of the quaternionic field. The Lorenz-like force acting on the moving body in the presence of this…
Anisotropy is very important to understand cosmic ray (CR) source and interstellar environment. The theoretical explanation of cosmic rays anisotropy from experiments remains challenging and even puzzling for a long time. In this paper, by…
Some time ago we have suggested that positive vacuum energy exhibits a finite quantum break time, which can be a signal that a positive cosmological constant is inconsistent. From the requirement that Universe never undergoes through…
We discuss the notion that quantum fields may induce an effective time-dependent cosmological constant which decays from a large initial value. It is shown that such cosmological models are viable in a non-de Sitter spacetime.
We study a Newtonian cosmological model in the context of a noncommutative space. It is shown that the trajectories of a test particle undergo modifications such that it no longer satisfies the cosmological principle. For the case of a…
The observed small value of cosmological constant can be naturally related with the scale of breaking down supersymmetry in agreement with other evaluations in particle physics.
If quantum fields exist in extra compact dimensions, they will give rise to a quantum vacuum or Casimir energy. That vacuum energy will manifest itself as a cosmological constant. The fact that supernova and cosmic microwave background data…
An overview on the present observational status and phenomenological understanding of cosmic rays above 10^16 eV is given. Above these energies the cosmic ray flux is expected to be gradually dominated by an extra-galactic component. In…
Old and new puzzles of cosmology are reexamined from the point of view of quantum theory of the universe developed here. It is shown that in proposed approach the difficulties of the standard cosmology do not arise. The theory predicts the…
Cosmic repulsion represented by a small positive value of the cosmological constant changes significantly properties of central gravitational fields at large distances, leading to existence of a static (or turnaround) radius where…
We investigate the coupled system of gravity and a scalar with exponential potential. The energy momentum tensor of the scalar field induces a time-dependent cosmological ``constant''. This adjusts itself dynamically to become in the…
The possibility that the Fermi scale is the only fundamental energy scale of Nature is under serious consideration at present, yet cosmic rays may already have provided direct evidence of new physics at a much higher scale. The recent…
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…
If the observed dark energy is a cosmological constant, the canonical state of the universe is de Sitter spacetime. In such a spacetime, quantum fluctuations that violate the null energy condition will create islands of matter that, if…
A novel, interesting class of scalar-tensor gravity theories is those with a limit on the field motion, where the scalar field either goes to a constant acceleration or stops accelerating and goes to a constant velocity. We combine these…