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V. Ch. Zhukovsky

Publications and source records attributed to V. Ch. Zhukovsky.

At least 37 records · Page 2Linked to original sources
arXiv2007

Synchrotron Radiation in the Standard Model Extension

We obtain a system of exact solutions of the Dirac equation for an electron moving in a constant homogeneous external magnetic field with account of its vacuum magnetic moment and assumed Lorentz invariance violation in the minimal CPT-odd form in the framework of the Standard Model Extension. Using these solutions, characteristics of the particle synchrotron radiation are calculated, and possible observable effects caused by the Lorentz non-invariant interaction are described. We demonstrate that the angular distribution of the radiation has specific asymmetry, which can be explained as a consequence of non-conservation of transversal electron polarization in the presence of a background Lorentz non-invariant condensate field.

hep-th↗
arXiv2007

Color superconductivity in the static Einstein Universe

We study the behavior of quark and diquark condensates in dense quark matter under the influence of a gravitational field adopting as a simple model the static $D-$dimensional Einstein Universe. Calculations are performed in the framework of the extended Nambu--Jona-Lasinio model at finite temperature and quark density on the basis of the thermodynamic potential and the gap equations. Quark and diquark condensates as functions of the chemical potential and temperature at different values of the curvature have been studied. Phase portraits of the system have been constructed.

hep-th↗
arXiv2006

Quark and pion condensation in a chromomagnetic background field

The general features of quark and pion condensation in dense quark matter with flavor asymmetry have been considered at finite temperature in the presence of a chromomagnetic background field modelling the gluon condensate. In particular, pion condensation in the case of a constant abelian chromomagnetic field and zero temperature has been studied both analytically and numerically. Under the influence of the chromomagnetic background field the effective potential of the system is found to have a global minimum for a finite pion condensate even for small values of the effective quark coupling constant. In the strong field limit, an effective dimensional reduction has been found to take place.

hep-ph↗
arXiv2006

Radiative Effects in the Standard Model Extension

The possibility of radiative effects induced by the Lorentz and CPT non-invariant interaction term for fermions in the Standard Model Extension is investigated. In particular, electron-positron photo-production and photon emission by electrons and positrons are studied. The rates of these processes are calculated in the Furry picture. It is demonstrated that the rates obtained in the framework of the model adopted strongly depend on the polarization states of the particles involved. As a result, ultra-relativistic particles produced should occupy states with a preferred spin orientation, i.e., photons have the sign of polarization opposite to the sign of the effective potential, while charged particle are preferably in the state with the helicity coinciding with the sign of the effective potential. This leads to evident spatial asymmetries which may have certain consequences observable at high energy accelerators, and in astrophysical and cosmological studies.

hep-ph↗
arXiv2005

Dissipative tunneling in structures with quantum dots and quantum molecules

The problem of tunneling control in systems "quantum dot - quantum well" (as well as "quantum dot - quantum dot" or quantum molecule) and "quantum dot - bulk contact" is studied as a quantum tunneling with dissipation process in the semiclassical (instanton) approximation. For these systems temperature and correlation between a quantum dot radius and a quantum well width (or another quantum dot radius) are considered to be control parameters. The condition for a single electron blockade is found in the limit of quantum dot. The criteria for an extreme tunneling current in quantum molecules are also presented. The tunnel probability for systems under investigation is analytically obtained as well.

cond-mat.stat-mech↗
arXiv2005

Gauge field theory for Poincaré-Weyl group

On the basis of the general principles of a gauge field theory the gauge theory for the Poincaré-Weyl group is constructed. It is shown that tetrads are not true gauge fields, but represent functions from true gauge fields: Lorentzian, translational and dilatational ones. The equations of gauge fields which sources are an energy-momentum tensor, orbital and spin momemta, and also a dilatational current of an external field are obtained. A new direct interaction of the Lorentzian gauge field with the orbital momentum of an external field appears, which describes some new effects. Geometrical interpretation of the theory is developed and it is shown that as a result of localization of the Poincaré-Weyl group spacetime becomes a Weyl-Cartan space. Also the geometrical interpretation of a dilaton field as a component of the metric tensor of a tangent space in Weyl-Cartan geometry is proposed.

hep-th↗
arXiv2005

Competition of Color Ferromagnetic and Superconductive States in a Quark-Gluon System

The possibility of color ferromagnetism in an SU(2) gauge field model is investigated. The conditions allowing a stable color ferromagnetic state of the quark system in the chromomagnetic field occupying small domains are considered. A phase transition between this state and the color superconducting state is considered. The effect of finite temperature is analyzed.

hep-ph↗
arXiv2004

Vacuum effects in electrodynamics and in Yang-Mills theory in (2+1) dimensions

Vacuum effects in (2+1)-dimensional quantum electrodynamics (QED) with the topological Chern-Simons term are considered. The photon polarization operator is studied and the decay rate for the electron-positron photoproduction is presented as a function of the photon energy and external field strength. The radiatively induced electron mass shift in an external magnetic field is investigated. The electron self-energy in topologically massive (2+1)-QED at finite temperature and density is studied. The parity breaking part of the Yang-Mills action in the framework of the $SU(2)\times U(1)$ gauge field model at finite temperature is considered.

hep-th↗
arXiv2004

Chern-Simons like term generation in an extended model of QED under external conditions

The possibility of a Chern-Simons like term generation in an extended model of QED, in which a Lorentz and CPT non-covariant interaction term for fermions is present, has been investigated at finite temperature and in the presence of a background color magnetic field. To this end, the photon polarization operator in an external constant axial-vector field has been considered. One-loop contributions to its antisymmetric component due to fermions in the linear order of the axial-vector field have been obtained. Moreover, the first nontrivial correction to the induced CS term due to the presence of a weak constant homogeneous color magnetic field has been derived.

hep-th↗
arXiv2002

Quark zero modes in intersecting center vortex gauge fields

The zero modes of the Dirac operator in the background of center vortex gauge field configurations in $\R^2$ and $\R^4$ are examined. If the net flux in D=2 is larger than 1 we obtain normalizable zero modes which are mainly localized at the vortices. In D=4 quasi-normalizable zero modes exist for intersecting flat vortex sheets with the Pontryagin index equal to 2. These zero modes are mainly localized at the vortex intersection points, which carry a topological charge of $\pm 1/2$. To circumvent the problem of normalizability the space-time manifold is chosen to be the (compact) torus $\T^2$ and $\T^4$, respectively. According to the index theorem there are normalizable zero modes on $\T^2$ if the net flux is non-zero. These zero modes are localized at the vortices. On $\T^4$ zero modes exist for a non-vanishing Pontryagin index. As in $\R^4$ these zero modes are localized at the vortex intersection points.

hep-th↗
arXiv2001

The Influence of an External Chromomagnetic Field on Color Superconductivity

We study the competition of quark-antiquark and diquark condensates under the influence of an external chromomagnetic field modelling the gluon condensate and in dependence on the chemical potential and temperature. As our results indicate, an external chromomagnetic field might produce remarkable qualitative changes in the picture of the color superconducting (CSC) phase formation. This concerns, in particular, the possibility of a transition to the CSC phase and diquark condensation at finite temperature.

hep-ph↗
arXiv2001

Chromomagnetic Catalysis of Color Superconductivity and Dimensional Reduction

We consider diquark condensation in external chromomagnetic fields at non--zero temperature. The general features of this process are investigated for various field configurations in relation to their symmetry properties and the form of the quark spectrum. According to the fields, there arises dimensional reduction by one or two units. In all cases there exists diquark condensation even at arbitrary weak quark attraction, confirming the idea about universality of this mechanism in a chromomagnetic field. Possible influence of a nonzero chemical potential on the results obtained is also discussed.

hep-th↗
arXiv2001

Chromomagnetic Catalysis of Chiral Symmetry Breaking and Color Superconductivity

It is shown in the framework of an extended NJL model with two flavors that some types of external chromomagnetic field induce the dynamical chiral or color symmetry breaking even at weakest attraction between quarks. It is argued also that an external chromomagnetic field, simulating the chromomagnetic gluon condensate of the real QCD-vacuum, might significantly influence the color superconductivity formation.

hep-ph↗
arXiv2001

Non-abelian plane waves and stochastic regimes for (2+1)-dimensional gauge field models with Chern-Simons term

An exact time-dependent solution of field equations for the 3-d gauge field model with a Chern-Simons (CS) topological mass is found. Limiting cases of constant solution and solution with vanishing topological mass are considered. After Lorentz boost, the found solution describes a massive nonlinear non-abelian plane wave. For the more complicate case of gauge fields with CS mass interacting with a Higgs field, the stochastic character of motion is demonstrated.

hep-th↗
arXiv2000

Magnetic catalysis in a P-even, chiral-invariant three-dimensional model with four-fermion interaction

The influence of an external constant and homogeneous magnetic field H on the phase structure of the P-symmetric, chiral invariant 3-dimensional field theory model with two four-fermion interaction structures is considered. An arbitrary small (nonzero) magnetic field is shown to induce spontaneous violation of the initial symmetry (magnetic catalysis). Moreover, vacuum of the model at H>0 can be either P-symmetric or chiral invariant, depending on the values of the coupling constants.

hep-ph↗
arXiv2000

Fermion in the Nonabelian Gauge Field Theory in 2+1 Dimensions

The massive SU(2) gauge field theory coupled with fermions is considered in 2+1 dimensions. Quark energy spectrum and radiative shift in constant external nonabelian field, being exact solution of the gauge field equations with the Chern-Simons term, are calculated. Under the condition $m = θ/4$ the quark state is shown to be supersymmetric.

hep-th↗