Yl. Klimontovich, FROM THE HAMILTONIAN-MECHANICS TO A CONTINUOUS MEDIA - DISSIPATIVE STRUCTURES - CRITERIA OF SELF-ORGANIZATION, Theoretical and mathematical physics, 96(3), 1993, pp. 1035-1056
The paper is aimed at presenting some main ideas and results of the mo
dern statistical theory of macroscopic open systems. We begin from the
demonstration of the necessity and the possibility of the unified des
cription of kinetic, hydrodynamic, and diffusion processes in nonlinea
r macroscopic open systems based on generalized kinetic equations. A d
erivation of the generalized kinetic equations is based on the concret
e physical definition of continuous media. A ''point'' of a continuous
medium is determined by definition of physically infinitesimal scales
. On the same basis, the definition of the Gibbs ensemble for nonequli
brium process is given. The Boltzmann gas and a fully ionized plasma a
s the test systems are used. For the transition from the reversible Ha
milton equations to the generalized kinetic equations the dynamic inst
ability of the motion of particles plays the constructive role. The ge
neralized kinetic equation for the Boltzmann gas consists of the two d
issipative terms: 1) the ''collision integral,'' defined by the proces
ses in a velocity space; 2) an additional dissipative term of the diff
usion type in the coordinate space. Owing to the latter the unified de
scription of the kinetic, hydrodynamic, and diffusion processes for al
l values of the Knudsen number becomes possible. The H-theorem for the
generalized kinetic equation is proved. The entropy production is def
ined by the sum of two independent positive terms corresponding to red
istribution of the particles in velocity and coordinate space respecti
vely. An entropy flux also consists of two paris. One is proportional
to the entropy, and the other is proportional to the gradient of entro
py. The existence of the second term allows one to give a general defi
nition of the heat flux for any values of the Knudsen number, which is
proportional to the gradient of entropy. This general definition for
small Knudsen number and constant pressure leads to the Fourier law. T
he equations of gas dynamic for a special class of distribution functi
ons follow from the generalized kinetic equation without the perturbat
ion theory for the Knudsen number. These equations differ from the tra
ditional ones by taking the self-diffusion processes into account. The
generalized kinetic equation for describing the Brownian motion and o
f autowave processes in active media is considered. The connection wit
h reaction diffusion equations, the Fisher-Kolmogorov-Petrovski-Piskun
ov and Ginzburg-Landau equations, is established. We discuss the conne
ction between the diffusion of particles in a restricted system with t
he natural flicker (1/f) noise in passive and active systems. The crit
eria of the relative degree of order of the states of open system - th
e criteria of self-organization, are presented.