Mathematics – Logic
Scientific paper
Mar 2012
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012aps..apr.x8001g&link_type=abstract
American Physical Society, APS April Meeting 2012, March 31-Apr 3, 2012, abstract #X8.001
Mathematics
Logic
Scientific paper
Cosmological N-body simulations are now being performed using Newtonian gravity on scales larger than the Hubble radius. It is known that a uniformly expanding, homogeneous ball of dust in Newtonian gravity satisfies the Friedmann equations, and also that a correspondence between Newtonian and relativistic dust cosmologies holds in linearized perturbation theory. Nevertheless, it is not obvious that Newtonian gravity can provide a good global description of an inhomogeneous cosmology with significant nonlinear dynamical behavior at small scales. We investigate this issue in light of a perturbative framework that we have recently developed. We propose a straightforward dictionary---exact at the linearized level---that maps Newtonian dust cosmologies into GR dust cosmologies, and we use our ordering scheme to determine the degree to which the resulting metric and matter distribution solve Einstein's equation. We then find additional corrections needed to satisfy Einstein's equation to ``order 1'' at small scales and to ``order ɛ'' at large scales. We expect that, in realistic Newtonian cosmologies, these additional corrections will be very small; if so, this should provide strong justification for the use of Newtonian simulations to describe GR cosmologies.
Green Stephen
Wald Robert
No associations
LandOfFree
Newtonian and Relativistic Cosmologies 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 Newtonian and Relativistic Cosmologies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Newtonian and Relativistic Cosmologies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1369118