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Information × Registration Number 0215U007723, 0115U004891 , R & D reports Title Dark energy and dark matter in astrophysical objects and cosmology popup.stage_title Head Serge Parnovsky, Registration Date 29-12-2015 Organization Taras Shevchenko Kiev university popup.description2 Final report on the research: 81 p., 19 fig., 4 tab., 64 sources. The terms - from 01/01/12 to 12/31/12. 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 considered the microlensing by the single point source with extended structures which can be represent by clumps of dark matter, with a spherically symmetric mass distribution regularl in the center. An analytical analysis of the lenzed image was done, the regions of parameters corresponding to the different number of images of a point source was defined . We calculate the time dependence of the amplification curves arising from the relative motion of the source and microlenses. Examples of scalar potential field and equations of state in the hydrodynamic model of cosmological expansion, which give the same behavior scale factor was considered. We consider the problems of models with a scalar field as a dynamic dark energy and the processes occurring in the vicinity of black holes. We found all possible types of singularities in a homogeneous Universe with an arbitrary state equation in the the framework of general relativity for both isotropic models, and anisotropic models for I, II, VI0, VII, VIII and IX types by Bianchi. We stydyed the propagation of ultrahigh-energy cosmic rays in galactic and intergalactic magnetic fields. A search for sources of cosmic rays observed clusters of extremely high-energy models and investigated their acceleration in active galactic nuclei and other powerful sources of radiation was done. In the modified gravity models we find an evolution of anisotropic cosmological models of Bianchi type. The example model of the universe, filled with dynamic scalar field shows that entropy production is not necessarily essential to the existence of the cosmological arrow of time. The system of differential equations that describe the evolution of cosmological perturbations on the brane. To determine the nature of the emission line at ~ 3.55 keV energy we analyze publicly available observations by MOS cameras on board the space X-ray Observatory XMM-Newton. 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 MAO, ITP, Space Research Institute 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 Гнатик Богдан Іванович Гнатик Роман Богданович Жданов Валерій Іванович Кудря Юрій Миколайович Парновський Сергій Людомирович Тимчук Оксана Олексіївна popup.nrat_date 2020-04-02 Close