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Information × Registration Number 0220U104569, 0120U105439 , R & D reports Title Generation and evolution of primary magnetic fields. popup.stage_title Head Gorbar Eduard V., Доктор фізико-математичних наук Registration Date 22-12-2020 Organization Taras Shevchenko National University of Kyiv popup.description2 Object of research: electromagnetic fields in the early universe, the Schwinger effect Purpose: to study the Schwinger effect (birth of charged particles by a strong electric field) in the expanding universe; describe the generation of electromagnetic fields during inflation in a kinetic relationship model taking into account the feedback. Research methods: quantum-kinetic approach, formalism of gradient decomposition, numerical methods. A system of quantum kinetic equations describing the birth of charged particles by an electric field in an expanding universe is derived from the first principles. The asymptotic behavior of kinetic functions at large values ​​of momentum is studied, and the terms that lead to ultraviolet differences in such observables as electric current and the energy-momentum tensor of born particles are separated. The renormalization procedure is performed and a self-consistent system of equations is obtained, which does not contain discrepancies. The generation of electromagnetic fields during inflation in the kinetic bond model has been studied. Using the formalism of the gradient decomposition, a system of coupled equations for bilinear functions of the electromagnetic field is derived. In addition to the usual amplification of electromagnetic modes through the interaction with inflaton, these equations also take into account the fact that the number of physically significant modes is constantly increasing during inflation. By breaking this system, it is shown that even with a relatively small number of equations, it is possible to describe the electrical and magnetic energy densities with an accuracy of several percent throughout the inflation stage.  Product Description popup.authors Voyzehovskiy Vadym V. Ivanchenko Iryna V. Momot Andrii І. Rudenok Igor V. Teslik Olena М. popup.nrat_date 2020-12-22 Close