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Information × Registration Number 0223U005053, 0120U104854 , R & D reports Title Light dark matter and dynamical dark energy in the Universe popup.stage_title Head Shtanov Yurii V., Доктор фізико-математичних наук Registration Date 13-12-2023 Organization М.М.Bogolyubov Institute of Theoretical Physics of the National Academy of Sciences of Ukraine popup.description2 Artifacts related to the resolution and discretization of the velocity field in N-particle cosmological simulations of warm dark matter are theoretically calculated. The properties of the large-scale structure in cosmological multi-particle simulations were studied using the methods of topological data analysis. The form and temporal evolution of Betti curves, as well as their independence of the resolution of the cosmological simulation, were established. Using Bayesian approaches, the values of the masses of fuzzy dark matter particles have been found that are preferred according to the kinematics of disk galaxies from the SPARC database. Possibilities for modifications of the standard cosmological model and ways to resolve the rension in the determination of the early and late Hubble constant are outlined. A constraint on the interaction parameter between dynamical quintessential dark energy and cold dark matter is found using data on the CMB anisotropy, baryon acoustic oscillations, and type Ia supernovae. Numerical solutions of Einstein's system of equations with a scalar field in static spherically symmetric configurations with asymptotically flat space-time are found. Observational manifestations of scalar-field dynamical dark energy are revealed. Asymptotic relations were established in the vicinity of the central naked singularity and the structure of accretion disks around it, which are determined by the ring-like distributions of stable circular orbits. Qualitative properties of Bianchi type I and II anisotropic homogeneous cosmological models with a general equation of state are analyzed. Qualitative regimes of cosmological expansion are classified, which include the possibilities of transition from expansion to compression, isotropization; a list of all possible types of future singularities is provided.  Product Description popup.authors Zhdanov Valery I. Neomenko Roman G. Parnovsky Serge L. Rudakovskyi Anton V. Savchenko Denys O. Stashko Oleksandr S. Khelashvili Mariia V. Tsizh Maxym B. Shtanov Yuri V. popup.nrat_date 2023-12-13 Close