Regular accelerating Universe without dark energy

Homogeneous isotropic cosmological models with two torsion functions filled with scalar fields and usual gravitating matter are built and investigated in the framework of the Poincar\'e gauge theory of gravity. It is shown that by certain restrictions on indefinite parameters of gravitational Lagrangian the cosmological equations at asymptotics contain an effective cosmological constant that can explain observable acceleration of cosmological expansion. The behavior of inflationary cosmological solutions at extremely high energy densities is analyzed, regular bouncing solutions are obtained. The role of the space-time torsion provoking the acceleration of cosmological expansion is discussed.Comment: 15 pages, 16 figures, iopart class file, some additions mad

Electromagnetic radiation and electromagnetic self-force of a point charge in the vicinity of Schwarzschild black hole

Point charge, radially moving in the vicinity of a black hole is considered. Electromagnetic field in wave zone and in the small neighbourhood of the charge is calculated. Numerical results of the calculation of the spectrum of electromagnetic radiation of the point charge are presented. Covariant approach for the calculation of electromagnetic self-force is used for the case of the slowly moving charge. Numerical results for the self-force in the case of slow motion of the particle are obtained and compared to the results in literature.Comment: 5 pages, 3 figure

Analysis of inflationary cosmological models in gauge theories of gravitation

Inflationary homogeneous isotropic cosmological models filled by scalar fields and ultrarelativistic matter are examined in the framework of gauge theories of gravitation. By using quadratic scalar field potential numerical analysis of flat, open and closed models is curried out. Properties of cosmological models are investigated in dependence on indefinite parameter of cosmological equations and initial conditions at a bounce. Fulfilled analysis demonstrates regular character of all cosmological models.Comment: LaTeX2e, iopart class file, 12 pages, 19 figure