The connection of the Callen–Welton and Nyquist fluctuation–dissipation relations is considered for plasma-like classical and quantum systems. The conditions for appearance of the dissipative parameters in the equilibrium current–current correlation function are investigated. The paper...

A self-consistent and universal description of friction and diffusion for Brownian particles (grains) in different systems, such as gases with Boltzmann collisions, dusty plasmas with ion absorption by grains, and for active particles (e.g., cells in biological systems), is suggested on the...

The granular gas dynamics under gravity is investigated by means of numerical simulation for the case of elastic collisions. Damped oscillations in the process of evolution to equilibrium are found and considered in detail. The nature of the oscillations is the deviation of the position of the...

The main goal of this paper is a rigorous consideration of the stress problem in some simple models of granular piles. Discrete models are considered and the transition to the continuous description is accomplished in order to find the coarse-grained average stress. Some phenomenological rules...

The effective pair macroion interaction for colloidal systems, obtained in general form by Trigger, Podloubny and Schram (TPS potential) is considered for the case of a strong Coulomb interaction between the macroion and counterion subsystems of a colloid. For this potential a good agreement...

The generalization of the Ward-Pitaevskii identity for many-particle systems with a potential of interparticle interaction, which is a sum of short-range and Coulomb parts, is obtained. The relations between this identity and the long-wavelength limit of density- density response functions and...

The properties of a Bose gas at low temperature are investigated by means of a rigorous theoretical analysis of a simple model. On the basis of the viral theorem and the dimensionality theory it is shown that the standard procedure of describing such system by using the c-numbers approximation...

By using the diagram technique of perturbation theory, the “density-density” response functions, the static structure factor, the longitudinal dielectric permittivity are analyzed in the long wavelength limit for the multicomponent Coulomb and neutral systems, and their relation to the...

The longitudinal and transverse conductivities of the disordered system of charge particles is considered. The linear response theory with respect to weak external field and the perturbation theory for the interaction between the particles and photons are investigated. The expressions for...

The impossibility of the transition to k → 0 under the integral for the current-current correlation function in the theory of conductivity of charged particles system is shown. A different possibility is investigated, when this transition is carried out in four-density correlation functions....