Related papers: Superheavy Particles in Friedmann Cosmology and th…
Atomic dark matter is usually considered to be produced asymmetrically in the early Universe. In this work, we first propose that the symmetric atomic dark matter can be thermally produced through the freeze-out mechanism. The dominant atom…
We present a mechanism to generate the baryon asymmetry of the Universe which preserves the net baryon number created in the Big Bang. If dark matter particles carry baryon number $B_X$, and $\sigma^{\rm annih}_{\bar{X}} < \sigma^{\rm…
Physically observable particles are assumed to result from an interaction between massless positively and negatively oriented 2-component Weyl neutrinos. A simple quantum mechanical analysis of a composite system of Weyl neutrinos of…
In the present universe visible and dark matter contribute comparable energy density although they have different properties. This coincidence can be elegantly explained if the dark matter relic density, originating from a dark matter…
It is now widely accepted that most of mass--energy in the universe is unobserved except by its gravitational effects. Baryons make only about 4% of the total, with "dark matter" making up about 23% and the "dark energy" responsible for the…
[A brief review intended for a general physics colloquium audience.] Astrophysicists now know that 80% of the matter in the universe is `dark matter', composed of neutral and weakly interacting elementary particles that are not part of the…
We study the possibility that dark matter is a baryon of a new strongly interacting gauge theory, which was introduced in the low energy theory of Cosmological SUSY Breaking (CSB). This particle can fit the observed dark matter density if…
High energy particles are produced by the annihilation of dark matter particles in our galaxy. These are presently searched for using balloon-borne antiproton and positron detectors and large area, deep underground neutrino telescopes. Dark…
A scenario that relates the abundance of dark matter to the baryon asymmetry of the Universe is presented. In this scenario, based on a left-right extension of the Standard Model, dark matter is made of light, ~ 1 GeV, right-handed Majorana…
We now know firmly that neutrinos have tiny masses, but in the minimal Standard Model there is no natural sources for such tiny masses. On the other hand, the extra heavy Z^{\prime 0} requires the extra Higgs field, the particle generating…
It is quite plausible that the mass of the dark matter particle increases significantly after its freeze-out, due to a scalar field rolling to large values. We describe a realization of this scenario in the context of thermal inflation…
It is shown that a first-order cosmological perturbation theory for Friedmann-Lemaitre-Robertson-Walker universes admits one and only one gauge-invariant variable which describes the perturbation to the energy density and which becomes…
Primordial superheavy particles, considered as the source of Ultra High Energy Cosmic Rays (UHECR) and produced in local processes in the early Universe, should bear some strictly or approximately conserved charge to be sufficiently stable…
In this work we study the possibility that primordial magnetic fields observed in galaxies could be produced by a dark matter halo made of charged ultra-light bosons. In the model, we assume that ultra-light bosons arise as excitations of a…
Dark Matter (DM) is omnipresent in our universe. Despite its abundance, the microscopic identity of DM still remains a mystery. Primordial black holes (PBHs), possibly formed via gravitational collapse of large density perturbations in the…
Probing the existence of hypothetical particles beyond the Standard model often deals with extreme parameters: large energies, tiny cross-sections, large time scales, etc. Sometimes laboratory experiments can test required regions of…
Based on the previously formulated theory of spherical perturbations in the cosmological medium of self-gravitating scalarly charged fermions with the Higgs scalar interaction and the similarity properties of such models, the formation of…
The understanding of the physical processes that lead to the origin of matter in the early Universe, creating both an excess of matter over anti-matter that survived until the present and a dark matter component, is one of the most…
For the first time, we have a plausible, complete accounting of matter and energy in the Universe. Expressed a fraction of the critical density it goes like this: neutrinos, between 0.3% and 15%; stars, 0.5%; baryons (total), 5%; matter…
We consider the possibility that the massive graviton is a viable candidate of dark matter in the context of bimetric gravity. We first derive the energy-momentum tensor of the massive graviton and show that it indeed behaves as that of…