General relativistic corrections to $N$-body simulations and the Zel'dovich approximation [CEA]

http://arxiv.org/abs/1505.04756


The initial conditions for $N$-body simulations are usually generated by applying the Zel’dovich approximation to the initial displacements of the particles using an initial power spectrum of density fluctuations generated by an Einstein-Boltzmann solver. We show that the initial displacements generated in this way generally receive a first-order relativistic correction. We define a new gauge, the $N$-body gauge, in which this relativistic correction is absent and show that a conventional Newtonian $N$-body simulation includes all first-order relativistic contributions if we identify the coordinates in Newtonian simulations with those in the $N$-body gauge.

Read this paper on arXiv…

C. Fidler, C. Rampf, T. Tram, et. al.
Tue, 19 May 15
59/78

Comments: 5 pages, 3 figures