Second-order perturbation theory in Omega is not equal to Friedmann models

Statistics – Computation

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

29

Astronomical Models, Computational Astrophysics, Cosmology, Perturbation Theory, Boundary Conditions, Density Distribution, Velocity Distribution

Scientific paper

This paper presents approximate second-order (quadratic) solutions for the density contrast and peculiar velocity field in Friedmann models with arbitrary density parameter Omega. It shows that the second-order perturbation equations are solvable if one can replace Omega exp 1.2 by Omega in one of the terms. These solutions are tested against exact solutions for spherical and sinusoidal perturbations, and comparisons with linear theory and with the Zel'dovich approximation are made. The quadratic solutions for the density contrast constitute a major improvement over the results of linear theory. That is not necessarily the case for the peculiar velocity field, as one must be very careful with the boundary conditions. The quadratic solutions and the Zel'dovich approximation are found to have similar accuracy. The applicability of these two different methods to concrete problems is discussed.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Second-order perturbation theory in Omega is not equal to Friedmann models does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Second-order perturbation theory in Omega is not equal to Friedmann models, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Second-order perturbation theory in Omega is not equal to Friedmann models will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1790227

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.