Selffocusing as a mechanism for the formation of dense structures inNewtonian cosmology.
Abstract
A simple nonlinear mechanism for producing galaxies from smaller initital perturbations than those required by linear perturbation theories is proposed. It is demonstrated that the multidimensional cubic nonlinear Schroedinger equations describe the slowlyvarying envelope of a nearly planefronted acoustic wave of moderately small amplitude in a uniformly expanding ideal fluid described by Newtonian gravity, where the background matter variables and expansion factor are treated as if they varied more slowly than anything else. The theory predicts occasional nearly pointlike concentrations of matter, for fluctuation wavenumbers greater than the critical Jeans' wavenumber, that might be promising candidates for protogalaxies.
 Publication:

Astronomy and Astrophysics
 Pub Date:
 November 1986
 Bibcode:
 1986A&A...168....1K
 Keywords:

 Big Bang Cosmology;
 Computational Astrophysics;
 Density Distribution;
 Galactic Evolution;
 Newton Theory;
 Self Focusing;
 Fluid Pressure;
 Ideal Fluids;
 Jeans Theory;
 Nonlinear Equations;
 Schroedinger Equation;
 Astrophysics;
 Cosmology;
 Galaxy Formation;
 Microwave Background:Anisotropy