Kinetics of small perturbations in an isotropic universe. III  Longwave perturbations in an ultrarelativistic gas
Abstract
Consideration is given to longwave gravitational perturbations in an isotropic expanding universe, filled with an ultrarelativistic gas. A kinetic approach in the collisionless approximation leads to the conclusion that scalar and vector perturbations, arising at a moment eta(0) much less than 1/n (where n is the wave vector and eta is the fourdimensional time coordinate), increase if the perturbation of the density of the macroscopic impulse of gas is nonzero at eta(0). This increase proceeds until the moment eta(1) = 2.7 eta(0), when the impulse density perturbation becomes zero. A solution is also obtained for tensor perturbations in the limit n eta much less than unity.
 Publication:

Fizika
 Pub Date:
 1978
 Bibcode:
 1978Fiz....21...37Z
 Keywords:

 Cosmic Gases;
 Density Wave Model;
 Gravity Anomalies;
 Isotropic Media;
 Perturbation Theory;
 Relativistic Plasmas;
 Collisionless Plasmas;
 Cosmology;
 Gravity Waves;
 Kinetic Theory;
 Astrophysics