[en] A lattice gauge model with the phase transition corresponding to spontaneous breakdown of the group center symmetry is considered. It is shown that the phase diagram, obtained in multicolor case, separates the high and low-temperature phases with confined and nonconfined quarks. The possibility of the Lorentz-invariant continuum limit in the phase with permanently confined quarks is confirmed

[en] The nature of parity doubling of baryon states with non-zero angular momentum is considered. The idea of explaining this phenomenon lies in the fact that the rotation of the gluon string leads to a centrifugal potential for quarks. The quarks on the string form a quark-diquark system. Quark tunneling from one end of the string to the other is not probable for systems with large angular momentum due to a large centrifugal potential, and the smallness of the underbarrier transition amplitude explains the small mass difference of the states with opposite parity. (orig.)

[en] It is shown that quantum effects give rise to the existence of instanton solutions in gauge theories with Higgs fields. A system of equations for instanton background in SU(2) gauge theory with Higgs isodublet is obtained one-loop approximation. The field disributions and value of action are obtained for the WS theory

[en] It is shown that the inclusion of quantum effects in theories with Higgs fields leads to instanton solutions of the equations of motion. In the one-loop approximation a coupled system of equations is obtained describing an instanton in the SU(2) gauge theory with a Higgs isodoublet. A modification of the loop expansion on the mean-field background is described, which can be used to calculate the instanton contributions to various physical quantities. The properties of the instanton in the SU(2) gauge theory with a Higgs isodoublet. A modification of the loop expansion on the mean-field background is described, which can be used to calculate the instanton contributions to various physical quantities. The properties of the instanton in the SU(2)xU(1) Weinberg-Salam theory are considered. It is shown that in this theory it is favorable to excite an abelian field B_mu in the field of the instanton, so that the action of the entire field configuration is decreased. Because of the difference between the masses of the W± and Z bosons, the instanton is asymmetric. The field distribution in the instanton is found in the Weinberg-Salam theory and its action is estimated (in the one-loop approximation). At large distances the instanton behaves as a four-dimensional electromagnetic dipole

[en] It is shown that quantum effects strongly influence the form of an instanton: the power-law asymptotic behavior ∼χ^-3 of the classical solution at large distances becomes ∼χ^-3 exp( - const α_sχ²/ρ²). A coupled system of Schwinger-Dyson equations is obtained for the vertex Green functions in the field of the instanton and it is shown that the gluon propagator on the background of instanton-like fluctuations does not contain infrared divergences

No abstract available

[en] The problem of quark confinement in quantum chromodynamics (QCD) from the view point of gauge group center symmetry, is investigated. For this purpose lattice gauge model is considered, where phase transition is connected with spontaneous breaking of the symmetry of the gauge group center. Two-charge QCD, studied by the methods of perturbation theory, is determined. A chain of contour movement equations for a two-charge model is derived, and by means of it the validity of the the factorized formula for loop means is proved. The dependence of the free energy on the external field for multicolour two-charge model coincides with the analogous value in U(1)-gauge theory. The phase diagram is obtained in the multicolour limit, is separates phases with confined and released quarks. Transition in the phase of quark confinement to the continuous Lorentz-invariant limit is briefly discussed

[en] Phenomenological theory of charmonium states with nonzero orbital momentum is constructed in the framework of QCD. Feinman representation for the amplitude of system (charmonium) transition from in to out states was obtained in the main approximation. Hamiltonian of the system with following parameters was constructed: k - string tension; mass of charmonium states; bond constant and anomalous magnetic moment of c-quark. Calculated values of charmonium mass spectrum for k0.176 GeV² are presented in comparison with available experimental data. Agreement of these data with obtained result is shown

[en] A perturbation theory for the wave functions of the monopole and dions is developed in the gauge theory with a gauge SU(2) group and the Higgs triplet of particles. Small as well as heavy dion charges are treated. Excited states of the monopole with non-zero spin are found

No abstract available