The adiabatic theory of galaxy formation
Abstract
The predictions of the theory of galaxy formation due to the gravitational condensation of adiabatic density perturbations in an otherwise Friedmann universe are examined in relation to those of standard nonlinear theories. An expression for the density contrast is derived in terms of adiabatic theory, which predicts the appearance of pancakes of anisotropically collapsing matter at a certain stage in the growth of density perturbations, and compared with those derived from the Newtonian nonlinear theory of gravitational instability, and from the general relativistic nonlinear theory of the gravitational instability of an isotropic system. It is shown that the anisotropic collapse of condensations of matter is by no means a general consequence of Newtonian cosmology. Predictions of relativistic and adiabatic theories are found to coincide only at redshifts greater than or equal to 20, at which pancake formation occurs in adiabatic theory.
 Publication:

Byulleten' Instituta Astrofiziki Dushanbe Akademiya Nauk Tadzhikskoj SSR
 Pub Date:
 1980
 Bibcode:
 1980BDus...69....9L
 Keywords:

 Adiabatic Conditions;
 Cosmology;
 Galactic Evolution;
 Gravitational Effects;
 Perturbation Theory;
 Gravitational Collapse;
 Isotropic Media;
 Motion Stability;
 Newton Theory;
 Prediction Analysis Techniques;
 Red Shift;
 Relativity;
 Universe;
 Astrophysics