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Oleg V. Kechkin

Publications and source records attributed to Oleg V. Kechkin.

At least 19 recordsLinked to original sources

Kink in dual dilaton-axion theories with potential

The representation in terms of Ernst's complex potential is used to describe and analyze dilaton-axion theories with potential. The set of such systems is divided into pairs of dual systems with respect to the inversion of the Ernst potential. Using duality, a theory is constructed that is invariant with respect to the nonlinear Ehlers transformation. For this theory, a soliton solution is obtained that is dual to a dilaton kink in a system that is invariant with respect to the axion shift transformation.

hep-th

Kink in the dilaton-axion theory with a potential possessing dilaton shift symmetry

The sigma model with dilaton and axion is generalized by including in it a potential that is invariant under the global transformation of the dilaton shift. In the (1 + 1)-dimensional case, a soliton is constructed, which turned out to be an axion-type kink (anti-kink) with a nontrivial distribution of the dilaton field. The solution is obtained for an arbitrary value of the dilaton-axion coupling constant, and its mass is found.

hep-th

Structures of General Relativity in Dilaton-Maxwell Electrodynamics

It is shown that electro (magneto) static sector of Maxwell's electrodynamics coupled to the dilaton field in a string theory form possesses the symmetry group of the stationary General Relativity in vacuum. Performing the Ernst formalism, we develope a technique for generation of exact solutions in this modified electrodynamics on the base of the normalized Ehlers symmetry transformation. In the electrostatic case, we construct and study a general class of spherically symmetric solutions that describes a point-like sourse of the Coulomb type. It is shown that this source is characterized by asymptotical freedom of the electrostatic interaction at short distances. Also it is established that the total electrostatic energy of this source is finite and inversely proportional to the dilaton-Maxwell coupling constant.

hep-th

Classical Dynamics of Quantum Numbers with Arrow of Time

We study a quantum theory with complex time parameter and non-Hermitian Hamiltonian structure. In this theory, the real part of the complex time is equal to `usual' physical time, whereas the imaginary one is proportional to inverse absolute temperature of the system. Then, the Hermitian part of the Hamiltonian coincides with conventional operator of energy; the anti-Hermitian part, which is taken as a symmetry operator, defines decay parameters of the theory. We integrate the equations of motion in a Hamiltonian proper basis, and detect a classical dynamics of the corresponding quantum numbers, using their continuous approximation and the zero limit of the Plank's constant. It is proved, that this dynamics possesses a well defined arrow of time in the isothermal and adiabatic regimes of the thermodynamical evolution of the system.

hep-th

Absolute Time and Temperature in Quantum and Classical Relativistic Mechanics

We present a relativistic quantum mechanics of a point mass with absolute thermodynamic time and temperature, combined to a single complex parameter of evolution. In this theory, the geometric time is introduced as one of space-time coordinates; it does not coincide with the thermodynamic time on the kinematical level. It is established, that the theory allows a consistent dynamics with nontrivial probability density at the limit $\hbar\to 0$. We identify this dynamics with the classical one, and prove its relativistic invariance. It is shown, that the thermodynamical time becomes proportional to the proper time of the point mass in the conventional classical regime of its evolution with the delta-functional distribution of the probability density.

hep-th

Gravity as Classical Effect in Generalized Relativistic Quantum Mechanics on Flat Background

We study classical limit for quantum mechanics with two times and temperature, which describes a generalized dynamics of relativistic point mass. In this theory, thermodynamic time means a parameter of evolution, whereas geometric time is one of space-time coordinates. We identify world lines in this theory with geodesic lines for the same point mass in standard General Relativity in its weak gravity limit. In identification performed, effective metrics is generated by weak correlations between canonical variables of the originally flat relativistic mechanics, i.e. between its space-time coordinates and moments.

hep-th

Generalized Quantum Dynamics with Arrow of Time

It is shown, that quantum theory with complex evolutionary time parameter and non-Hermitian Hamiltonian structure can be used for natural unification of quantum and thermodynamic principles. The theory is postulated as analytical in respect to the parameter of evolution, which real part is identified with the `usual' physical time, whereas the imaginary one is understood as proportional to the inverse absolute temperature. Also, the Hermitian part of the Hamiltonian is put equal to conventional operator of energy. It is shown, that the anti-Hermitian Hamiltonian part, which is taken as commuting with the energy operator, is constructed from parameters of decay of the system. It is established, that quantum dynamics, predicted by this theory, is integrable in the same sense as the corresponding non-modified one, and that it possesses a well defined arrow of time in isothermal and adiabatic regimes of the evolution. It is proved, that average value of the decay operator decreases monotonously (as the function of the physical time) in these important thermodynamical regimes for the arbitrary initial data taken. We discuss possible application of the general formalism developed to construction of time-irreversible modification of a string theory.

hep-th

Parity Violation and Arrow of Time in Generalized Quantum Dynamics

It is shown, that parity violation in quantum systems can be a natural result of their dynamical evolution. The corresponding (completely integrable) formalism is based on the use of quantum theory with complex time and non-Hermitian Hamiltonian. It is demonstrated, that starting with total symmetry between left and right states at the initial time, one obtains strictly polarized system at the time infinity. The increasing left-right asymmetry detects a presence of well-defined arrow of time in evolution of the system. We discuss possible application of the general formalism developed to construction of modified irreversible dynamics of massless Dirac fields (in framework of superstring theory, for example).

hep-th

String theory extensions of Einstein-Maxwell fields: the stationary case

We present a new approach for generating solutions in heterotic string theory compactified down to three dimensions on a torus with d+n>2, where d and n stand for the number of compactified space--time dimensions and Abelian gauge fields, respectively. It is shown that in the case when d=2k+1 and n is arbitrary, one can apply a solution--generating procedure starting from solutions of the stationary Einstein theory with k Maxwell fields; our approach leads to classes of solutions which are invariant with respect to the total group of three-dimensional charging symmetries. We consider a particular extension of the stationary Einstein--multi-Maxwell theory obtained on the basis of the Kerr--multi-Newman--NUT special class of solutions and establish the conditions under which the resulting multi--dimensional metric is free of Dirac string peculiarities.

hep-th

String theory extensions of Einstein-Maxwell fields: the static case

We present a new approach for generation of solutions in the four-dimensional heterotic string theory with one vector field and in the five-dimensional bosonic string theory starting from the static Einstein-Maxwell fields. Our approach allows one to construct the solution classes invariant with respect to the total subgroup of the three-dimensional charging symmetries of these string theories. The new generation procedure leads to the extremal Israel-Wilson-Perjes subclass of string theory solutions in a special case and provides its natural continuous extension to the realm of non-extremal solutions. We explicitly calculate all string theory solutions related to three-dimensional gravity coupled to an effective dilaton field which arises after an appropriate charging symmetry invariant reduction of the static Einstein-Maxwell system.

hep-th

Heterotic string theory interrelations

We establish a symmetry map which relates two low-energy heterotic string theories with different numbers of the Abelian gauge fields compactified from the diverse to three dimensions on a torus. We discuss two applications of the established symmetry: a generation of the heterotic string theory solutions from the stationary Einstein-Maxwell fields and one non-trivial submersion of the heterotic string theory into the bosonic one.

hep-th

Generation of heterotic string theory solutions from the stationary Einstein-Maxwell fields

A new formalism for construction of the stationary solutions is developed for the four-dimensional gravity coupled to the dilaton, Kalb-Ramond and two Maxwell fields in a low-energy heterotic string theory form. The result of generation is automatically invariant in respect to subgroup of the stationary charging symmetry transformations; the generation can be started from the stationary Einstein-Maxwell fields. The formalism is given both in real and new compact complex form, the result of maximal symmetry extension of the stationary Einstein-Maxwell theory to discussing string gravity model is explicitly written down.

gr-qc

Generation of the bosonic string theory solutions from the stationary Einstein fields via projection symmetry

A new formalism for generation of solutions in the consistently truncated low-energy bosonic string theory is developed. This formalism gives a correspondence of the projection type between the theories toroidally compactified from the diverse to three dimensions. Taking the stationary Einstein-dilaton gravity as the theory with a lower dimension, we generate its bosonic string theory extension and calculate the bosonic string theory solution corresponding to the Kerr-NUT one modified by the presence of the charged dilaton field.

gr-qc

Kalb--Ramond dipole solution in low-energy bosonic string theory

We construct a new solution subspace for the bosonic string theory toroidally compactified to 3 dimensions. This subspace corresponds to the complex harmonic scalar field coupled to the effective 3--dimensional gravity. We calculate a class of the asymptotically flat and free of the Dirac string peculiarity solutions which describes a Kalb--Ramond dipole source with the generally nontrivial dilaton charge.

gr-qc

3D heterotic string theory: new approach and extremal solutions

We develop a new formalism for the bosonic sector of low-energy heterotic string theory toroidally compactified to three dimensions. This formalism is based on the use of some single non-quadratic real matrix potential which transforms linearly under the action of subgroup of the three-dimensional charging symmetries. We formulate a new charging symmetry invariant approach for the symmetry generation and straightforward construction of asymptotically flat solutions. Finally, using the developed approach and the established formal analogy between the heterotic and Einstein-Maxwell theories, we construct a general class of the heterotic string theory extremal solutions of the Israel-Wilson-Perjes type. This class is asymptotically flat and charging symmetry complete; it includes the extremal solutions constructed before and possesses the non-trivial bosonic string theory limit.

hep-th

New progress in the stationary D=N=4 supergravity

A bosonic sector of the four-dimensional low-energy heterotic string theory with two Abelian gauge fields is considered in the stationary case. A new 4X4 unitary null-curvature matrix representation of the theory is derived and the corresponding formulation based on the use of a new 2X2 Ernst type matrix complex potential is developed. The group of hidden symmetries is described and classified in the matrix-valued quasi General Relativity form. A subgroup of charging symmetries is constructed and representation which transforms linearly under the action of this symmetry subgroup is established. Also the solution generation procedure based on the application of the total charging symmetry subgroup to the stationary Einstein-Maxwell theory is analyzed.

gr-qc

Chiral models in dilaton-Maxwell gravity

We study symmetry properties of the Einstein-Maxwell theory nonminimaly coupled to the dilaton field. We consider a static case with pure electric (magnetic) Maxwell field and show that the resulting system becomes a nonlinear sigma-model wich possesses a chiral representation. We construct the corresponding chiral matrix and establish a representation which is related to the pair of Ernst-like potentials. These potentials are used for separation of the symmetry group into the gauge and nongauge (charging) sectors. New variables, which linearize the action of charging symmetries, are also established; a solution generation technique based on the use of charging symmetries is formulated. This technique is used for generation of the elecricaly (magneticaly) charged dilatonic fields from the static General Relativity ones.

gr-qc

Bosonic string - Kaluza Klein theory exact solutions using 5D-6D dualities

We present the explicit formulae which allow to transform the general solution of the 6D Kaluza--Klein theory on a 3--torus into the special solution of the 6D bosonic string theory on a 3--torus as well as into the general solution of the 5D bosonic string theory on a 2--torus. We construct a new family of the extremal solutions of the 3D chiral equation for the SL(4,R)/SO(4) coset matrix and interpret it in terms of the component fields of these three duality related theories.

gr-qc