Searcharxiv⌕ Search

arXiv subjects

J. Manjavidze

Publications and source records attributed to J. Manjavidze.

35 records · Page 2Linked to original sources
arXiv2000

Dual-Resonance Model and Multiple Production

The very high multiplicity (VHM) processes are considered to investigate consequences of the dual resonance models reach (exponential) mass spectrum. The virial decomposition is developed for description of the produced particles short-rang (resonance) correlations. It is shown that the reach mass spectrum is able to do more flat the VHM distribution: $\s_n=O(e^{-n})$ up to multiplicities $n\simeq\bar{n}^2$, $\bar{n}$ is the mean multiplicity. But for $n>>\bar{n}^2$ one should expect $\s_n<O(e^{-n})$.

hep-ph↗
arXiv2000

Generating functionals method of N.N.Bogolyubov and multiple production physics

The generating functionals (GF) method in Bogolyubov's formulation and its application for particle physics is considered. Effectiveness of the method is illustrated by two examples. So, GF method can be used as the technical trick solving the infinite sequence of algebraic equations. We will consider the example, where GF allows express the multiplicity distributions (topological cross sections) through the particles correlation functions (inclusive cross sections) to `predict' so called the Koba-Nielsen-Olesen scaling. We will use the GF to define validity of the thermal description of the multiple production phenomena also. It will be seen that this will lead to the `correlations relaxation condition' of N.N.Bogolyubov. This will allow to offer the experimentally measurable criteria of applicability of thermodynamical description of multiple production processes. In results we will find the closed form of perturbation theory applicable for kinetic phase of nonequilibrium processes. It is shown a way as the approach may be adapted to the definite external conditions.

hep-ph↗
arXiv2000

Phase transitions signal in inelastic hadron collisions

The consequence of vacuum instability against particles creation is described using lattice gas model. It is shown that the tail of multiplicity distribution should decrees slower than any power of $\exp\{-n\}$, but faster than any power of $1/n$ if the vacuum is unstable against particles creation.

hep-ph↗
arXiv2000

Quantisation of Extended Objects

The `strong-coupling' perturbation theory over the inverse interaction constant $1/g$ near the nontrivial solution of Lagrange equation is formulated. The ordinary `week-coupling' perturbation theory over $g$ is described also to compare both perturbation theories. The `strong-coupling' perturbation theory is developed by unitary mapping of the quantum dynamics into the space with local coordinates of (action, angle)-type.

hep-th↗
arXiv1999

Some notes about multiplicity distribution at hadron colliders

The idea that the hard processes are dominate at the very high multiplicity (VHM) final states creation is considered. For this purpose quantitative realization of the Pomeron, DIS and large-angle annihilation (LAA) mechanism combinations are considered in the pQCD frame. The phase transition (condensation) in the soft pions system is described as the alternative to above mechanism. It is shown that in compared to QCD prediction last one predicts enhancement in the VHM distribution tail.

hep-ph↗
arXiv1999

Fields topology and perturbation theory

The fields nonlinear modes quantization scheme is discussed. New form of the perturbation theory achieved by unitary mapping the quantum dynamics in the space $W_G$ of (action, angle)-type collective variables. It is shown why the transformed perturbation theory contributions may accumulated exactly on the boundary $\pa W_G$. Abilities of the developed formalism are illustrated by examples from quantum mechanics and field theory.

hep-th↗
arXiv1998

High-Multiplicity Processes (Theoretical status)

We wish to demonstrate that investigation of asymptotically high multiplicity (AHM) hadron reactions may solve, or at least clear up, a number of problems unsolvable by other ways. We would lean upon the idea: (i) the entropy is proportional to multiplicity and, by this reason, at the AHM domain one may expect the equilibrium final state and (ii) the high-multiplicity processes becomes hard. Last one means that the nonperturbative corrections are frozen during this processes and the QCD predictions are available for them.

hep-ph↗
arXiv1998

Fields topology and observables

The paper contains successive description of the strong-coupling perturbation theory. Formal realization of the idea is based on observation that the path-integrals measure for absorption part of amplitudes $\R$ is Diracian ($\d$-like). New form of the perturbation theory achieved mapping the quantum dynamics in the space $W_G$ of (action, angle) type collective variables. It is shown that the transformed perturbation theory contributions are accumulated on the boundary $\pa W_G$, i.e. are sensible to the $topology$ of factor space $W_G$ and,therefore, to the theory symmetry group $G$. The abilities of our perturbation theory are illustrated by examples from quantum mechanics and field theory. Considering the Coulomb potential $1/|x|$ the total reduction of quantum degrees of freedom is demonstrated mapping the dynamics in the (angle, angular momentum, Runge-Lentz vector) space. To solve the (1+1)-dimensional sin-Gordon model the theory is considered in the space (coordinates, momenta) of solitons. It is shown the total reduction of quantum degrees of freedom and, in result, there is not multiple production of particles. This result we interpret as the $S$-matrix form of confinement. The scalar $O(4,2)$-invariant field theoretical model is quantized in the $W_O=O(4,2)/O(4) {\times} O(2)$ factor manifold. It is shown that the corresponding $\R$ is nontrivial because of the scale invariance breaking.

hep-th↗
arXiv1998

Example of quantum systems reduction

To solve the quantum-mechanical problem the procedure of mapping onto linear space $W$ of generators of the (sub)group violated by given classical trajectory is formulated. The formalism is illustrated by the plane H-atom model. The problem is solved noting conservation of the Runge-Lentz vector $n$ and reducing the 4-dimensional incident phase space $T$ to the 3-dimensional linear subspace $W=T^* V\times R^1$, where $T^* V$ is the (angular momentum ($l$) - angle ($\vp$)) phase space and $R^1 =n$. It is shown explicitly that (i) the motion in $R^1$ is pure classical as the consequence of the reduction, (ii) motion in the $\vp$ direction is classical since the Kepler orbits are closed independently from initial conditions and (iii) motion in the $l$ direction is classical since all corresponding quantum corrections are defined on the bifurcation line ($l=\infty$) of the problem. In our terms the H-atom problem is exactly quasiclassical and is completely integrable by this reasons.

hep-th↗
arXiv1998

Wigner functions of essentially nonequilibrium systems

The aim of the article is to discuss the S-matrix interpretation of perturbation theory for the Wigner functions generating functional at a finite temperature. For sake of definiteness, fruitful from pedagogical point of view, the concrete problem from particle physics of high-temperature initial states dissipation into cold one is considered from experimental and theoretical points of view. The temperature is introduced in the theory by typical for the microcanonical description way. The perturbation theory contains two- temperature (of initial and final states) Green functions. Two possible boundary conditions are considered. One of them is usual in a field theory vacuum boundary condition. Corresponding generating functional of Wigner functions can be used in the particle physics. Another type of the boundary condition assumes that the system under consideration is in environment of the black-body radiation. This leads to the usual in statistics Kubo-Martin-Schwinger boundary condition at the equilibrium (one-temperature) limit. The comparison of the S-matrix approach with Schwinger-Keldysh real-time finite-temperature field theory and with nonstationary statistical operator approach of Zubarev are considered. The range of applicability of the finite-temperature description of dissipation processes is shown.

hep-ph↗
arXiv1998

Perturbation theory in the invariant subspace

The unitary transformation of path-integral differential measure is described. The main properties of perturbation theory in the phase space of action-angle, energy-time variables are investigated. The measure in cylindrical coordinates is derived also. The dependence of perturbation theory contributions from global (topological) properties of corresponding phase spaces is shown.

hep-th↗
arXiv1995

The path integrals on a curved manifold

For description of the quantum dynamics on a curved group manifold the path integrals in a space of the group parameters is offered. The formalism is illustrated by the $H$-atom problem.

hep-ph↗
arXiv1995

$S$-matrix description of the finite-temperature noneqilibrium media

The paper contains the real-time perturbation theory for description of a statistical system with the nonuniform temperature distribution. the formalism based on the Wigner-functions approach. The perturbation theory is formulated in terms of the local-temperature Green functions.

hep-ph↗
arXiv1995

On the cancelation of quantum-mechanical corrections at the periodic motion

The paper contains description of the path integrals in the action-angle phase space. It allows to split the action and angle degrees of freedom and to show that the angular quantum corrections cancel each other if the classical classical trajectory is periodic. The example considered in the paper shows that the quantum problem can be quasiclassical over the part (angular in the considered case) degrees of freedom.

hep-ph↗
arXiv1995

The unitary transformation of the path-integral measure

The aim of the article is to show how a coordinate transformation can be applied to the path-integral formalism. For this purpose the unitary definition of the quantum measure, which guarantees the conservation of total probability, is offered. As the examples, the phase space transformation to the canonically conjugate pare $(energy, time)$ and the transformation to the cylindrical coordinates are shown. The transformations of the path-integral measure looks classically but they can not be deduced from naive transformations of quantum trajectories.

quant-ph↗