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Ashot S. Gevorkyan

Publications and source records attributed to Ashot S. Gevorkyan.

9 recordsLinked to original sources
arXiv2019

Quantum Vacuum: The Structure of Empty Space-Time and Quintessence with Gauge Symmetry Group $SU(2)\otimes U(1)$

We consider the formation of structured and massless particles with spin 1, by using the Yang-Mills like stochastic equations system for the group symmetry $SU(2)\otimes U(1)$ without taking into account the nonlinear term characterizing self-action. We prove that, in the first phase of relaxation, as a result of multi-scale random fluctuations of quantum fields, massless particles with spin 1, further referred as \emph{hions}, are generated in the form of statistically stable quantized structures, which are localized on 2$D$ topological manifolds. We also study the wave state and the geometrical structure of the \emph{hion} when as a free particle and, accordingly, while it interacts with a random environment becoming a quasi-particle with a finite lifetime. In the second phase of relaxation, the vector boson makes spontaneous transitions to other massless and mass states. The problem of entanglement of two \emph{hions} with opposite projections of the spins $+1$ and $-1$ and the formation of a scalar zero-spin boson are also thoroughly studied. We analyze the properties of the scalar field and show that it corresponds to the Bose-Einstein (BE) condensate. The scalar boson decay problems, as well as a number of features characterizing the stability of BE condensate, are also discussed. Then, we report on the structure of empty space-time in the context of new properties of the quantum vacuum, implying on the existence of a natural quantum computer with complicated logic, which manifests in the form of dark energy. The possibilities of space-time engineering are also discussed.

physics.gen-ph↗
arXiv2015

On the motion of classical three-body system with consideration of quantum fluctuations

We study the multichannel scattering in the classical three-body system and show that the problem can be formulated as a motion of the point mass on a curved hyper-surface of the energy of the body-system. It is proved that the local coordinate system on curved space produces additional symmetries which along with known integrals of motion allow to reduce the initial problem to the system of the sixth order. Assuming, that the metric of the curved space has a random component, we derive the system of \emph{stochastic differential equations} (SED) describing the classical motion of the three-body system taking into account the influence of random forces of various origin and in particular the quantum fluctuations. Using SDEs of motion, we obtain the partial differential equation of the second order describing the probability distribution of the point mass in the momentum representation. It is shown, that the equation for the probability distribution is solved jointly with the classical equations, which in turn are responsible for the topological peculiarities of tubes of quantum currents and transitions between asymptotic channels. The latter allows to solve the problem of the limiting transition from the quantum region to the region of classical chaotic motion (Poincaré region) without violating the analogue of Arnold's theorem on quantum mapping. The expression characterizing a measure of deviation of the quantum probabilistic currents and thus the appearance of quantum chaos in a dynamical system is determined.

math-ph↗
arXiv2006

A New Approach To The Evaluation Of The S-Matrix In Atom-Diatom Quantum Reactive Scattering Theory

A new approach is described to the evaluation of the S-matrix in three-dimensional atom-diatom reactive quantum scattering theory. The theory is developed based on natural collision coordinates where progress along the reaction coordinate can be viewed as fulfilling the same role as time in a time-dependent formulation. By writing the full wavefunction in coupled-channel form it is proved that the 3D quantum reactive scattering problem can be treated in the same way as an inelastic single-arrangement problem. In particularly, two types of coupled-channel representations, which are reduced to two different systems of coupled first order ordinary differential equations describing the inelastic scattering, are used. The first system of coupled differential equations is constructed on a set of points (grid) of the coordinate reaction curve after solution of many 1D Schroedinger problems in the directions normal to the reaction coordinate. The second expression for inelastic scattering is found using exactly solvable nonstationary 1D Schroedinger equation (etalon equation method), which is introduced for describing the localization properties of the full wavefunction along the curve of coordinate reaction. In this case we avoid a large amount of computation involved in solving the 1D Schroedinger problem along the reaction coordinate by using a slightly difficult initial conditions for the inelastic scattering equations. In both cases by solving the system of coupled first order ordinary differential equations, the full wavefunction and all S-matrix elements are obtained simultaneously without further calculations. Our analysis shows that the methods we have developed constitute the simplest algorithms for computing the reactive scattering S-matrices.

physics.chem-ph↗
arXiv2006

Regular and Chaotic Quantum Dynamic in Atom-Diatom Reactive Collisions

A new micro-irreversible 3D theory of quantum multichannel scattering in the three-body system is developed. The quantum approach is constructed on the generating trajectory tubes which allow taking into account influence of classical non-integrability on the dynamical quantum system. It was shown that when the volume of classical chaos in phase space is larger than quantum sell in the main object of quantum system the wavefunction generates chaos (quantum chaos). The probability of quantum transitions is constructed for this case. On the example of collinear collision of Li+(FH) -> (LiF)+H system is carried out the numerical calculation and was shown that in the system is generated quantum (wave) chaos.

quant-ph↗
arXiv2006

New Approach for Stochastic Quantum Processes, their Manipulation and Control

The dissipation and decoherence (for example, the effects of noise in quantum computations), interaction with thermostat or in general with physical vacuum, measurement and many other complicated problems of open quantum systems are a consequence of interaction of quantum system with the environment. These problems are described mathematically in terms of complex probabilistic process (CPP). Particularly, treating the environment as a Markovian process we derive an Langevin-Schroedinger type stochastic differential equation (SDE) for describing the quantum system interacting with environment. For the 1D randomly quantum harmonic oscillator (QHO) model L-Sh SDE is a solution in the form of orthogonal CPP. On the basis of orthogonal CPP the stochastic density matrix (SDM) method is developed and in its framework relaxation processes in the uncountable dimension closed system of "QHO+environment" is investigated. With the help of SDM method the thermodynamical potentials, like nonequilibrium entropy and the energy of ground state are exactly constructed. The dispersion for different operators are calculated. In particular, the expression for uncertain relations depending on parameter of interaction with environment is obtained. The Weyl transformation for stochastic operators is specified. Ground state Winger function is developed in detail.

math-ph↗
arXiv2006

Random 3D Spin System Under the External Field and Dielectric Permittivity Superlattice Formation

A dielectric medium consisting of roughly polarized molecules is treated as a 3D disordered spin system (spin glass). A microscopic approach for the study of statistical properties of this system on micrometer space scale and nanosecond time scale of standing electromagnetic wave is developed. Using ergodic hypothesis the initial 3D spin problem is reduced to two separate 1D problems along external field propagation. The first problem describes the disordered spin chain system while the second one describes a disordered N-particle quantum system with relaxation in the framework of Langevin-Schroedinger (L-Sch) type equation. Statistical properties of both systems are investigated in detail. Basing on these constructions, the coefficient of polarizability, related to collective orientational effects, is calculated. Clausius-Mossotti formula for dielectric constant is generalized. For dielectric permittivity function generalized equation is found taking into account Clausius-Mossotti generalized formula.

cond-mat.soft↗
arXiv1997

New Perturbation Theory for Nonstationary Anharmonic Oscillator

The new perturbation theory for the problem of nonstationary anharmonic oscillator with polynomial nonstationary perturbation is proposed. As a zero order approximation the exact wave function of harmonic oscillator with variable frequency in external field is used. Based on some intrinsic properties of unperturbed wave function the variational-iterational method is proposed, that make it possible to correct both the amplitude and the phase of wave function. As an application the first order correction are proposed both for wave function and S-matrix elements for asymmetric perturbation potential of type $V(x,τ)=α(τ)x^3+β(τ)x^4.$ The transition amplitude ''ground state - ground state'' $W_{00}(λ;ρ)$ is analyzed in detail depending on perturbation parameter $λ$ (including strong coupling region $% λ$ $\sim 1$) and one-dimensional refraction coefficient $ρ$.

quant-ph↗
arXiv1997

Random motion of quantum reactive harmonic oscillator. Thermodynamics of Vacuum of Asymptotic Subspace

The system of oscillator interacting with vacuum is considered as a problem of random motion of quantum reactive harmonic oscillator (QRHO). It is formulated in terms of a wave functional regarded as complex probability process in the extended space. This wave functional obeys some stochastic differential equation (SDE). Based on the nonlinear Langevin type SDE of second order, introduced in the functional space R{W(t)}, the variables in original equation are separated. The general measure in the space R{W(t)} of the Fokker-Plank type is obtained and expression for total wave function (wave mixture) of random QRHO is constructed as functional expansion over the stochastic basis set. The pertinent transition matrix S_br is constructed. For Wiener type measure W(t) of functional space the exact representation for ''vacuum-vacuum'' transition probability is obtained. The thermodynamics of vacuum is described in detail for the asymptotic space R1_as. The exact values for Energy, shift and expansion of ground state of oscillator and its Entropy are calculated.

quant-ph↗