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Information × Registration Number 0216U007645, 0116U006218 , R & D reports Title Dark energy and dark matter in astrophysical objects and cosmology popup.stage_title Head Serge Parnovsky, Registration Date 29-12-2016 Organization Taras Shevchenko Kiev University popup.description2 Object of study - the whole Universe, galaxies, cosmic rays, gravitational lenses. Purpose - Getting new knowledge about the nature of extremal astrophysical and cosmological phenomena, where a significant role can play an expantion of the standard cosmological model and modifications of general relativity, searching effects of the "new physics". Research methods - methods of theoretical physics and astrophysics, numerical modeling. We study the dynamics of a homogeneous model of Bianchi type IX with timelike and spacelike singularities. We find solutions of the joint system of Einstein equations and scalar field describing a spherically symmetric static configuration around a central naked singularity or a black hole and analyzed the motion of test bodies. We studied a behaviour of homogeneous isotropic universe with general barotropic equation of state. For the 4 close giant galaxies (M81, NGC3368, the Milky Way, M31) we constructed profiles of orbital mass and density profiles of the dark matter halo. The approximate formulas for the time delay of the point source image located near caustic were developed. .We studied an influence of galactic and intergalactic magnetic fields on the propagation of cosmic rays of the highest energies. It has been shown that some of the registered events can be caused by a nearby galaxy with an active nucleus Virgin A. We find potential sources of triplet events: microquasars SS433 and GRS1915 + 105 and the magnetar SGR 1900 + 14. We analysed multi-wavelength observations of the large-scale jet of the quasar 3C273. We studied the influence of the dark matter in the form of sterile neutrinos which can explain the emission line at 3.5 keV, on the process of reionization of the Universe. We detected such radiation outside the central part of the Galaxy. It was found a difference between the concentrations of dark matter halos in the models of sterile neutrinos and the model of cold dark matter. We described the evolution of cosmological perturbations in the multicomponent universe on a brane with a phantom-like evolution of dark energy. An approach in which the gravitational interaction is described in terms of the gauge field of SO (3) is considered. The results are of interest to extragalactic astronomy, astrophysics and cosmology; they are introduced in the educational process and used for reading astronomical courses and in research work in ITP, MAO and other institutes of NAS of Ukraine. Extragalactic astronomy, the theory of gravity, astrophysics, cosmology, general relativity, dark matter, dark energy, cosmic rays Product Description popup.authors Александров Олександр Миколайович Гнатик Богдан Іванович Гнатик Роман Богданович Жданов Валерій Іванович Кудря Юрій Миколайович Парновський Сергій Людомирович Сташко Олександр Сергійович popup.nrat_date 2020-04-02 Close