Related papers: Problems of Dark Matter
An extension of the Standard Model by three right-handed neutrinos with masses smaller than the electroweak scale (the $\nu$MSM) can explain simultaneously dark matter and baryon asymmetry of the Universe, being consistent with the data on…
This paper provides a review of the variants of dark matter which are thought to be fundamental components of the universe and their role in origin and evolution of structures and some new original results concerning improvements to the…
We consider the effects of a massive, unstable neutrino on the evolution of large--scale structure and anisotropies in the cosmic microwave background. Comparison with large--scale structure data allows us to rule out a wide range of masses…
Numerous observations point towards the existence of an unknown elementary particle with no electromagnetic interactions, a large population of which was presumably produced in the early stages of the history of the Universe. This so-called…
There is a puzzling contradiction: direct observations favor a low-mass density universe, but the only model which fits universe structure over more than three orders of magnitude in distance scale has a mix of hot (neutrino) and cold dark…
One of the prime pieces of evidence for dark matter is the observation of large overdense regions in the universe. Since we know from the cosmic microwave background that the regions that contained the most baryons when the universe was…
Stars account for only about 0.5% of the content of the Universe; the bulk of the Universe is optically dark. The dark side of the Universe is comprised of: at least 0.1% light neutrinos; 3.5% +/- 1% baryons; 29% +/- 4% cold dark matter;…
We investigate how the nature of dark energy affects the determination of the curvature of the universe from recent observations. For this purpose, we consider the constraints on the matter and dark energy density using observations of type…
The nature of the main constituents of the mass of the universe is one of the outstanding riddles of cosmology and astro-particle physics. Current models explaining the evolution of the universe, and measurements of the various components…
We propose a simple model in which the cosmological dark matter consists of particles whose mass increases with the scale factor of the universe. The particle mass is generated by the expectation value of a scalar field which does not have…
In recent years, unprecedented progress in observational cosmology has revealed a great deal of information about the formation and evolution of structures in the universe. This, in turn, has raised many challenging issues for the…
A degenerate fermionic vacuum population is suggested. Based on the abundance of the dark energy density in the Universe the vacuum particle mass and number density are estimated. The obtained mass is in reasonable agreement with…
Measurement of accelerated expansion in the Universe led to propose a new cosmic fluid as its cause: dark energy. Its various incarnations offer a wealth of models whose relevance it is important to discriminate via contacts with…
Observations in the optical, in X-rays, and gravitational lensing of galaxies, clusters of galaxies, and large-scale structure are beginning to provide clues to the dark matter problem. I review the impact of these observations on some of…
Dark matter has been recognized as an essential part of matter for over 70 years now, and many suggestions have been made, what it could be. Most of these ideas have centered on Cold Dark Matter, particles that are expected in extensions of…
Modern cosmology successfully deals with the origin and the evolution of the Universe at large scales, but it is unable to completely answer the question about the nature of the fundamental objects that it is describing. As a matter of…
I review the observational data most relevant for large scale structure. These data determine the system of cosmological parameters: the Hubble parameter, densities of various populations of the Universe, parameters characterizing the power…
Cosmology yields the most restrictive limits on neutrino masses and conversely, massive neutrinos would contribute to the cosmic dark-matter density and would play an important role for the formation of structure in the universe. Neutrino…
In the past years a wealth of observations has unraveled the structural properties of dark and luminous mass distribution in galaxies, a benchmark for understanding dark matter and the process of galaxy formation. The study of the…
Recent cosmological observations suggest that nearly seventy per cent of the energy density in the universe is unclustered and has negative pressure. Several conceptual issues related to the modeling of this component (`dark energy'), which…