Gravitational particle production in braneworld cosmology

Gravitational particle production in time variable metric of an expanding universe is efficient only when the Hubble parameter $H$ is not too small in comparison with the particle mass. In standard cosmology, the huge value of the Planck mass $M_{Pl}$ makes the mechanism phenomenologically irrelevant. On the other hand, in braneworld cosmology the expansion rate of the early universe can be much faster and many weakly interacting particles can be abundantly created. Cosmological implications are discussed.Comment: 4 pages, 1 figure, v3 with new definition of $\Lambda$ and minor text modification

Baryogenesis, 30 Years after

A review of the basic principles of baryogenesis is given. Baryogenesis in heavy particle decays as well as electroweak, SUSY-condensate, and spontaneous baryogenesis are discussed. The models of abundant creation of antimatter in the universe are briefly reviewed.Comment: 30 pages, latex twic

Cosmic antimatter: models and phenomenology

The possibility of creation of cosmologically significant antimatter are analyzed in different scenarios of baryogenesis. It is argued that there may exist plenty of antimatter even in our Galaxy. Possible forms of antimatter objects and their observational signatures are discussed.Comment: 6 pages; invited talk at 14th Lomonosov Conference, Moscow University, August, 200

Cosmological Constraints on Neutrino Masses and Mixings

The bounds on neutrino masses and mixing that follows from the data on light element abundances, large scale structure formation, and angular fluctuations of cosmic microwave background radiation are analyzed. The role of neutrino oscillations in BBN and the bounds on cosmological lepton asymmetry are discussed.Comment: Talk presented at the NOON 2003 workshop, February 10-14, 2003, Kanazawa, Japan (to be published in the Proceedings), 10 page

Early formed astrophysical objects and cosmological antimatter

Astronomical observations of recent years show that the universe at high redshifts about ten is densely populated by the early formed objects: bright galaxies, quasars, gamma-bursters, and contains a lot of metals and dust. Such rich early formed varieties have not been expected in the standard model of formation of astrophysical objects. There is serious tension between the standard theory and observations.We describe the model which naturally relaxes this tension and nicely fits the data. The model naturally leads to creation of cosmologically significant antimatter which may be abundant even in the Galaxy. Phenomenological consequences of our scenario and possibility of distant registration of antimatter are discussed.Comment: 16 pages; invited talks presented at the conferences: 2015: The Spacetime Odyssey Continues, NORDITA, Stockholm, ,June 2 - 5, 2015; 4th V.N. Gribov Memorial Workshop, June, 17-20, 2015, Chernogolovka, Russia; ICGAC-12, XIIth International Conference on Gravitation, Astrophysics and Cosmology, June 28-July 5, 2015, PFUR, Moscow, Russi

Light millicharged particles and large scale cosmic magnetic fields

After a brief review of different types of scenarios suggested for the solution of the problem of galactic and intergalactic magnetic field generation, the mechanism based on the electric current induction by hypothetical millicharged particles interacting with electrons in cosmic medium is discussed. The proposed model successfully describes observational data. The new light millicharged particles can contribute from a small fraction up to 100% to the cosmological dark matter.Comment: 6 pages, no figures; talk presented at Sixteenth Lomonosov Conference On Elementary Particle Physics, Moscow State University, Moscow, 22-28 August, 201