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Yuri N. Obukhov

Publications and source records attributed to Yuri N. Obukhov.

149 records · Page 9Linked to original sources

Regular solutions in Abelian gauge model

The regular solutions for the Ginzburg-Landau (-Nielsen-Olesen) Abelian gauge model are studied numerically. We consider the static isolated cylindrically symmetric configurations. The well known (Abrikosov) vortices, which present a particular example of such solutions, play an important role in the theory of type II superconductors and in the models of structure formation in the early universe. We find new regular static isolated cylindrically symmetric solutions which we call the type B and the flux tube solutions. In contrast to the pure vortex configurations which have finite energy, the new regular solutions possess a finite Gibbs free energy. The flux tubes appear to be energetically the most preferable configurations in the interval of external magnetic fields between the thermodynamic critical value $H_{c}$ and the upper critical field $H_{c_2}$, while the pure vortex dominate only between the lower critical field $H_{c_1}$ and $H_{c}$. Our conclusion is thus that type B and flux tube solutions are important new elements necessary for the correct understanding of a transition from the vortex state to the completely normal state.

hep-th↗

Analogue of black string in the Yang--Mills gauge theory

The classical Yang--Mills equations are analyzed within the geometrical framework of an effective gravity theory. Exact analytical solutions are derived for the cylindrically symmetric configurations of the coupled gauge and isoscalar fields. It turns out that there is an infinite family of solutions parametrized by two real parameters, one of which determines the asymptotic behavior of fields near the symmetry axis and in infinity, while the second locates the singularity. These configurations have a simple pole at a finite value of the radial coordinate, and physically they represent ``thick string''-like objects which possess the confinement properties. It is demonstrated that the particles with gauge charge cannot move classically and quantum mechanically out of the interior region. Such an objects are thus direct analogues of the ``black string'' gravitational configurations reported recently in the literature.

hep-th↗

Vortices, flux tubes and other structures in the Ginzburg-Landau model: a possible fine structure of the mixed state?

We present new regular static isolated cylindrically symmetric solutions for the Ginzburg-Landau model which have finite Gibbs free energy. These configurations (which we call the {\it flux tube} and {\it type B} solutions) are energetically favorable in the interval of the external magnetic fields between the thermodynamic critical value $H_{c}$ and the upper critical field $H_{c_2}$ which indicates that they are important new elements of the mixed state describing a transition from vortices to the normal state.

hep-th↗

Vacuum Einstein Equations in Terms of Curvature Forms

A closed explicit representation of the vacuum Einstein equations in terms of components of curvature 2-forms is given. The discussion is restricted to the case of non-vanishing cubic invariant of conformal curvature spinor. The complete set of algebraic and differential identities connecting particular equations is presented and their consistency conditions are analyzed.

gr-qc↗