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A. V. Minkevich

Publications and source records attributed to A. V. Minkevich.

At least 19 recordsLinked to original sources

Gauge gravitation theory in Riemann-Cartan space-time and the nonsingular Universe

The gauge gravitation theory in the Riemann-Cartan space-time is investigated in order to solve the fundamental problems of the general relativity theory. The constraints for indefinite parameters of the theory under which solutions of isotropic cosmology describe a nonsingular accelerating Universe are given. Numerical solutions of cosmological equations near the limiting energy density by transition from gravitational compression to expansion in dependence on energy density in the case of flat, closed and open models are obtained. Some physical consequences of gauge gravitational theory in the Riemann-Cartan space-time in astrophysics are discussed.

gr-qc

Gauge gravitation theory in Riemann-Cartan space-time and gravitational interaction

The place and physical significance of gauge gravitation theory in the Riemann-Cartan space-time (GTRC) in the framework of gauge approach to gravitation is discussed. Isotropic cosmology built on the base of GTRC with general expression of gravitational Lagrangian with indefinite parameters is considered. The most important physical consequences connected with the change of gravitational interaction, with possible existence of limiting energy density and gravitational repulsion at extreme conditions, and also with the vacuum repulsion effect are discussed. The solution of the problem of cosmological singularity and the dark energy problem as result of the change of gravitational interaction is considered.

gr-qc

Torsion and gravitational interaction in Riemann-Cartan space-time

The influence of space-time torsion on gravitational interaction at cosmological and astrophysical scales is discussed within the framework of gauge gravitation theory in Riemann-Cartan space-time. It is shown that the interaction of the vacuum torsion with proper angular momentums of gravitating objects leads to appearance of additional gravitational force which can be manifested at astrophysical scale.

gr-qc

Vacuum torsion and regular accelerating Universe without dark matter

The simplest gauge gravitation theory in Riemann-Cartan space-time leading to the solution of the problem of cosmological singularity and dark energy problem is investigated with purpose to solve the dark matter problem. It is shown that the interaction of the vacuum torsion field with proper angular moments of gravitating objects can lead to appearance at astrophysical scale (galaxies, galactic clusters) additional force of gravitational attraction, which in the frame of standard theory is connected with dark matter.

gr-qc

Relationship of gauge gravitation theory in Riemann-Cartan spacetime and general relativity theory

The simplest variant of gauge gravitation theory in Riemann-Cartan spacetime leading to the solution of the problem of cosmological singularity and dark energy problem is investigated. It is shown that this theory by certain restrictions on indefinite parameters of gravitational Lagrangian in the case of usual gravitating systems leads to Einstein gravitational equations with effective cosmological constant.

gr-qc

To theory of asymptotically stable accelerating Universe in Riemann-Cartan spacetime

Homogeneous isotropic cosmological models built in the framework of the Poincaré gauge theory of gravity based on general expression of gravitational Lagrangian with indefinite parameters are analyzed. Special points of cosmological solutions for flat cosmological models at asymptotics and conditions of their stability in dependence of indefinite parameters are found. Procedure of numerical integration of the system of gravitational equations at asymptotics is considered. Numerical solution for accelerating Universe without dark energy is obtained.

gr-qc

On theory of regular accelerating Universe in Riemann-Cartan spacetime

Isotropic cosmology built in the Riemann-Cartan spacetime is investigated. Properties of homogeneous isotropic cosmological models filled with usual gravitating matter and scalar fields are studied in the beginning of cosmological expansion near the limiting energy density. It is shown that cosmological models are regular not only with respect to the Hubble parameter and the energy density but also with respect to the torsion and curvature tensors.

gr-qc

On some physical aspects of isotropic cosmology in Riemann-Cartan spacetime

Isotropic cosmology built in the framework of the Poincaré gauge theory of gravity based on sufficiently general expression of gravitational Lagrangian is considered. The derivation of cosmological equations and equations for torsion functions in the case of the most general homogeneous isotropic models is given. Physical aspects of isotropic cosmology connected with possible solution of dark energy problem and problem of cosmological singularity are discussed.

gr-qc

Numerical analysis of cosmological models for accelerating Universe in Poincare gauge theory of gravity

Homogeneous isotropic models with two torsion functions built in the framework of the Poincare gauge theory of gravity based on general expression of gravitational Lagrangian by certain restrictions on indefinite parameters are analyzed numerically. Special points of cosmological solutions at asymptotics and conditions of their stability in dependence of indefinite parameters are found. Procedure of numerical integration of the system of gravitational equations at asymptotics is considered. Numerical solution for accelerating Universe without dark energy and dark matter is obtained. It is shown that by certain restrictions on indefinite parameters obtained cosmological solutions are in agreement with SNe Ia observational data and Big Bang Nucleosynthesis predictions. Statefinder diagnostics is discussed in order to compare considered cosmological model with other models.

gr-qc

Gravitation and regular Universe without dark energy and dark matter

It is shown that isotropic cosmology in the Riemann-Cartan spacetime allows to solve the problem of cosmological singularity as well as the problems of invisible matter components - dark energy and dark matter. All cosmological models filled with usual gravitating matter satisfying energy dominance conditions are regular with respect to energy density, spacetime metrics and the Hubble parameter. At asymptotics cosmological solutions of spatially flat models describe accelerating Universe without dark energy and dark matter, and quantitatively their behaviour is identical to that of standard cosmological ΛCDM-model.

gr-qc

De Sitter spacetime with torsion as physical spacetime in the vacuum

Homogeneous isotropic models built in the framework of the Poincaré gauge theory of gravity (PGTG) based on general expression of gravitational Lagrangian without cosmological constant are analyzed. It is shown that the physical spacetime in the vacuum in the frame of PGTG can have the structure of flat de Sitter spacetime with torsion. Some physical consequences of obtained conclusion are discussed.

gr-qc

Comment on "Torsion Cosmology and Accelerating Universe"

Cosmological solutions for homogeneous isotropic models in the framework of the Poincaré gauge theory of gravity based on gravitational Lagrangian adopted in the paper by Kun-Feng Shie, James M. Nester and Hwei-Jang Yo (Phys. Rev. D \textbf{78}, 023522 (2008)) are discussed. Cosmological solutions for accelerating Universe obtained in referred paper are compared with corresponding solutions of standard $ΛCDM$-model and also with cosmological solution obtained by authors of this Comment.

gr-qc

Accelerating Universe with spacetime torsion but without dark matter and dark energy

It is shown that cosmological equations for homogeneous isotropic models deduced in the framework of the Poincaré gauge theory of gravity by certain restrictions on indefinite parameters of gravitational Lagrangian take at asymptotics the same form as cosmological equations of general relativity theory for $ΛCDM$-model. Terms related to dark matter and dark energy in cosmological equations of standard theory for $ΛCDM$-model are connected in considered theory with the change of gravitational interaction provoked by spacetime torsion.

gr-qc

To theory of gravitational interaction

Some principal problems of general relativity theory and attempts of their solution are discussed. The Poincare gauge theory of gravity as natural generalization of Einsteinian gravitation theory is considered. The changes of gravitational interaction in the frame of this theory leading to the solution of principal problems of general relativity theory are analyzed.

gr-qc

Analysis of regular inflationary cosmological models with two torsion functions in Poincare gauge theory of gravity

Analysis of regular inflationary cosmological models with two torsion functions filled with scalar field with quadratic potential and ultrarelativistic matter is carried out numerically. Properties of different stages of regular inflationary cosmological solutions are studied, restrictions on admissible values of parameters and initial conditions at transition from compression to expansion are found. The structure of extremum surface in space of physical variables is investigated.

gr-qc

Regular accelerating Universe without dark energy

Homogeneous isotropic cosmological models with two torsion functions filled with scalar fields and usual gravitating matter are built and investigated in the framework of the Poincaré gauge theory of gravity. It is shown that by certain restrictions on indefinite parameters of gravitational Lagrangian the cosmological equations at asymptotics contain an effective cosmological constant that can explain observable acceleration of cosmological expansion. The behavior of inflationary cosmological solutions at extremely high energy densities is analyzed, regular bouncing solutions are obtained. The role of the space-time torsion provoking the acceleration of cosmological expansion is discussed.

gr-qc

Gravitation, Cosmology and Space-Time Torsion

Poincaré gauge theory of gravity offers opportunities to solve some principal problems of general relativity theory and modern cosmology. In the frame of this theory the gravitational interaction can have the repulsion character in the case of usual gravitating matter with positive values of energy density and pressure satisfying energy dominance condition. Cosmological consequences of gravitational repulsion are considered in the case of homogeneous isotropic models in connection with the problem of cosmological singularity and dark energy problem of general relativity theory. Regular Big Bang inflationary scenario with accelerating stage of cosmological expansion at asymptotics and the principal role of space-time torsion in this scenario are discussed.

gr-qc

Homogeneous isotropic cosmological models with pseudoscalar torsion function in Poincare gauge theory of gravity and accelerating Universe

The "dark energy" problem is investigated in the framework of the Poincare gauge theory of gravity in 4-dimensional Riemann-Cartan space-time. By using general expression for gravitational Lagrangian homogeneous isotropic cosmological models with pseudoscalar torsion function are built and investigated. It is shown that by certain restrictions on indefinite parameters of gravitational Lagrangian the cosmological equations at asymptotics contain effective cosmological constant and can lead to observable acceleration of cosmological expansion. This effect has geometrical nature and is connected with space-time torsion.

gr-qc