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Sergei G. Matinyan

Publications and source records attributed to Sergei G. Matinyan.

8 recordsLinked to original sources

To the Theory of Unstable States

Deviations of the decay law from exponents are discussing for a long time, however, experimental proofs of such deviations are absent. Here in the general form is shown that the conclusions about non-exponential contributions are due to the disregarding of advanced interactions, i.e. at principally non-relativistic considerations. We consider decay processes in the frame of interactions duration of the quantum field theory. We show that at this basis the usual exponential decay has place.

quant-ph↗

Adventures of the Coupled Yang-Mills Oscillators: I. Semiclassical Expansion

We study the quantum mechanical motion in the $x^2y^2$ potentials with $n=2,3$, which arise in the spatially homogeneous limit of the Yang-Mills (YM) equations. These systems show strong stochasticity in the classical limit ($\hbar = 0$) and exhibit a quantum mechanical confinement feature. We calculate the partition function $Z(t)$ going beyond the Thomas-Fermi (TF) approximation by means of the semiclassical expansion using the Wigner-Kirkwood (WK) method. We derive a novel compact form of the differential equation for the WK function. After separating the motion in the channels of the equipotential surface from the motion in the central region, we show that the leading higher-order corrections to the TF term vanish up to eighth order in $\hbar$, if we treat the quantum motion in the hyperbolic channels correctly by adiabatic separation of the degrees of freedom. Finally, we obtain an asymptotic expansion of the partition function in terms of the parameter $g^2\hbar^4t^3$.

quant-ph↗

Adventures of the Coupled Yang-Mills Oscillators: II. YM-Higgs Quantum Mechanics

We continue our study of the quantum mechanical motion in the $x^2y^2$ potentials for $n=2,3$, which arise in the spatially homogeneous limit of the Yang-Mills (YM) equations. In the present paper, we develop a new approach to the calculation of the partition function $Z(t)$ beyond the Thomas-Fermi (TF) approximation by adding a harmonic (Higgs) potential and taking the limit $v\to 0$, where $v$ is the vacuum expectation value of the Higgs field. Using the Wigner-Kirkwood method to calculate higher-order corrections in $\hbar$, we show that the limit $v\to 0$ leads to power-like singularities of the type $v^{-n}$, which reflect the possibility of escape of the particle along the channels in the classical limit. We show how these singularities can be eliminated by taking into account the quantum fluctuations dictated by the form of the potential.

quant-ph↗

Chaos in Non-Abelian Gauge Fields, Gravity, and Cosmology

This talk describes the evolution of studies of chaos in Yang-Mills fields, gravity, and cosmology. The main subject is a BKL regime near the singularity $t=0$ and its survival in higher dimensions and in string theory. We also describe the recent progress in the search for particle-like solutions of the Einstein-Yang-Mills system (monopoles and dyons), colored black holes and the problem of their stability.

gr-qc↗

A Model of Charmonium Absorption by Light Mesons

We calculate the cross sections for dissociation of $J/ψ$ by pions and $ρ$-mesons within the framework of a meson exchange model. We find that these cross sections are small at center-of-mass energies less than 1 GeV above threshold, and that dissociation rates are less than 0.01 $c$/fm in a thermal meson gas at temperatures where such a description makes sense.

nucl-th↗

Lasers as a Bridge between Atomic and Nuclear Physics

This paper reviews the application of optical and UV laser radiation to several topics in low-energy nuclear physics. We consider the laser-induced nuclear anti-Stokes transitions, the laser-assisted and the laser-induced internal conversion, and the Electron Bridge and Inverse Electron Bridge mechanisms as tools for deexciting and exciting of low-lying nuclear isomeric states. A study of the anomalous, by low-lying, nuclear isomeric states (on an example of the $^{229}$Th nucleus) is presented in detail.

nucl-th↗

Gluon Radiation and Coherent States in Ultrarelativistic Nuclear Collisions

We explore the correspondence between classical gluon radiation and quantum radiation in a coherent state for gluons produced in ultrarelativistic nuclear collisions. The expectation value of the invariant momentum distribution of gluons in the coherent state is found to agree with the gluon number distribution obtained classically from the solution of the Yang-Mills equations. A criterion for the applicability of the coherent state formalism to the problem of radiation in ultrarelativistic nucleus-nucleus collisions is discussed. This criterion is found to be fulfilled for midrapidity gluons with perturbative transverse momenta larger than about 1-2 GeV and produced in collisions between valence partons.

nucl-th↗

Quantum Fluctuations and Dynamical Chaos: An Effective Potential Approach

We discuss the intimate connection between the chaotic dynamics of a classical field theory and the instability of the one-loop effective action of the associated quantum field theory. Using the example of massless scalar electrodynamics, we show how the radiatively induced spontaneous symmetry breaking stabilizes the vacuum state against chaos, and we speculate that monopole condensation can have the same effect in non-Abelian gauge theories.

hep-th↗