ar X iv : a st ro - p h / 03 02 54 4 v 1 2 6 Fe b 20 03 Application of the Separate Universe Approach to Preheating

ar X iv : a st ro - p h / 03 02 17 7 v 1 1 0 Fe b 20 03 Polarization in GRB Afterglows

ar X iv : a st ro - p h / 03 02 42 4 v 1 2 0 Fe b 20 03 Stochastic appearance in stars and high energy sources

Many phenomena such as stellar variability, stellar explosions, behavior of different kind of X-ray and gamma-ray sources, processes in active galactic nuclei and other astrophysical objects show stochastic features. Brief description of these phenomena is given in this review.

ar X iv : a st ro - p h / 03 02 48 0 v 1 2 4 Fe b 20 03 23 Field and cluster RR Lyrae stars as stellar tracers

We present an overview on pulsation properties of RR Lyrae stars in the Galaxy and in Local Group dwarf galaxies. We discuss the key information that RR Lyrae might provide on their parent population, and in particular on their metallicity distribution.

ar X iv : a st ro - p h / 03 02 25 9 v 1 1 3 Fe b 20 03 Chemical Composition of the Early Universe

A prediction of standard inflationary cosmology is that the elemental composition of the medium out of which the earliest stars and galaxies condensed consisted primarily of hydrogen and helium He with small admixtures of deuterium, lithium Li, and He. The most red-shifted quasars, galaxies, and Ly-α absorbers currently observed, however, all exhibit at least some admixture of heavier elements,...

ar X iv : a st ro - p h / 06 02 26 4 v 1 1 2 Fe b 20 06 DENSITY PERTURBATION IN THE UNIVERSE WITH NONTRIVIAL TOPOLOGY OF SPACE - TIME

A space spectrum of density perturbation In the Universe with nontrivial topol-ogy of space-time is shown to become discrete.