The effect of dissipative processes on the evolution of the density perturbations in an expanding isotropic Universe.
Abstract
The gaugeinvariant equations describing the evolution of the potential perturbations of the critical density in an isotropic Universe filled with a dissipative gas medium are derived in the gravitational stability theory. The equations are shown to be reduced to the singularly perturbed thirdorder equation nonlinear in a series of parameters, what provides the bifurcation properties of its solutions. Near the singular point the dynamic stability breaking of the system takes place, being accompanied by the anomalous growth of the density clots which have rather small peculiar velocities. This effect is interpreted as a generation of the dissipative structure in an expanding Universe. One of the possible critical points, which has apparently an interest for the galaxy generation theory, is located at t = 10^{16}s when the principal mass of the baryon subsystem of Universe is concentrated in neutral hydrogen and helium. The effect of cold dark matter on the character of nonequilibrium phase transition in the baryon subsystem is evaluated.
 Publication:

Zhurnal Eksperimentalnoi i Teoreticheskoi Fiziki
 Pub Date:
 February 1992
 Bibcode:
 1992ZhETF.101..385V
 Keywords:

 Dark Matter;
 Energy Dissipation;
 Gravitation Theory;
 Interstellar Gas;
 Universe;
 Computational Astrophysics;
 Isotropic Media;
 Perturbation Theory;
 Astrophysics