Hairy black holes in the general Skyrme model

We study the existence of hairy black holes in the generalized Einstein-Skyrme model. It is proven that in the BPS model limit there are no hairy black hole solutions, although the model admits gravitating (and flat space) solitons. Furthermore, we find strong evidence that a necessary condition for the existence of black holes with Skyrmionic hair is the inclusion of the Skyrme term $\mathcal{L}_4$. As an example, we show that there are no hairy black holes in the $\mathcal{L}_2+\mathcal{L}_6+\mathcal{L}_0$ model and present a new kind of black hole solutions with compact Skyrmion hair in the $\mathcal{L}_4+\mathcal{L}_6+\mathcal{L}_0$ model.Comment: Latex file, 19 pages, 9 ps figures; v2: minor changes, some comments added, coincides with published versio

Dynamical Boson Stars

The idea of stable, localized bundles of energy has strong appeal as a model for particles. In the 1950s John Wheeler envisioned such bundles as smooth configurations of electromagnetic energy that he called {\em geons}, but none were found. Instead, particle-like solutions were found in the late 1960s with the addition of a scalar field, and these were given the name {\em boson stars}. Since then, boson stars find use in a wide variety of models as sources of dark matter, as black hole mimickers, in simple models of binary systems, and as a tool in finding black holes in higher dimensions with only a single killing vector. We discuss important varieties of boson stars, their dynamic properties, and some of their uses, concentrating on recent efforts.Comment: 79 pages, 25 figures, invited review for Living Reviews in Relativity; major revision in 201

Polarized Effects in Two-Boson Production by Fermion - Antifermion Annihilation

The Lorentz-invariant matrix element of polarized bosons and fermions annihilation was obtained in the frame of Standard Model of electroweak interaction. Differential and total cross sections were calculated and analyzed. Polarized effects were studied. The problem of discrimination of Standard Model result and nonminimal gauge theories prediction is discussed

Polarized Effects in Two-Boson Production by Fermion - Antifermion Annihilation

The Lorentz-invariant matrix element of polarized bosons and fermions annihilation was obtained in the frame of Standard Model of electroweak interaction. Differential and total cross sections were calculated and analyzed. Polarized effects were studied. The problem of discrimination of Standard Model result and nonminimal gauge theories prediction is discussed