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Information × Registration Number 0224U031762, 0122U001957 , R & D reports Title Fundamental laws of physics in the cosmology of the early universe popup.stage_title Head Horbar Eduard V., Доктор фізико-математичних наук Registration Date 12-06-2024 Organization Taras Shevchenko National University of Kyiv popup.description2 Nature of dark matter is one of the most intriguing problems of modern physics and astrophysics. One interesting hypothesis is that dark matter is composed of ultralight bosons which could form a Bose-Einstein condensate (BEC). Solving the Gross-Pitaevskii-Poisson equations for the galactic self-gravitating BEC, the density and velocity profiles of dark matter were found for two types of stable structures with spherically-symmetric and vortical BEC. The key obtained result is that the observable effects for spherically-symmetric and vortex cores yield different density and velocity distributions which could essentially affect the dynamics of baryonic matter in the galactic halo, especially in its inner region. The rotational velocity induced by the halo with vortex is smaller close to the core region compared to the case of non-rotating halo. Stability of solitonic structures of self-gravitating Bose-Einstein condensates was studied and it was found that vortex solitons survive even after head-oncollision. The quantum nature of BEC leads to the formation of topological excitations in the form of vortex rings and Josephson vortices during collisions. It is found that axion inflation is a very efficient generator of chirality with numerically calculated chiral imbalance for typical values of parameters is about 25-27 % of the fermion number density. Consequently, the produced chirality should be taken into account in the study of magnetogenesis in axion inflationary model and the subsequent evolution of generated magnetic fields in the early Universe. A new method has been developed to separate spectral contributions in X-ray spectra for systems containing an active galactic nucleus (AGN) surrounded by a cluster. Product Description popup.authors Vizniuk Oleksandr V. Horkavenko Tetiana V. Zadorozhna Lidiia V. Lysenko Anastasiia V. Momot Andrii І. Sobol Oleksandr O. Teslyk Olena М. popup.nrat_date 2024-06-12 Close