Pairwise Infall Velocity and Acceleration in the Zel'dovich Approximation
Abstract
Using perturbative methods, nonlinear corrections to the mean pairwise infall velocity and acceleration are investigated both in the Zel'dovich approximation and in the higher order Eulerian perturbation theory. We calculate the second-order corrections to these two quantities, and find that for a typical cold-dark-matter model, predictions of the Zel'dovich approximations are considerably different from that of the Eulerian perturbation theory, even on quasi-linear scales. This is an important caveat against the application of this approximation to quantities closely related to the dynamical nature of structure formation.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- April 1999
- DOI:
- 10.1093/pasj/51.2.233
- Bibcode:
- 1999PASJ...51..233S
- Keywords:
-
- ANALYTICAL METHODS;
- COSMOLOGY;
- GALAXIES: CLUSTERING;
- GRAVITATION