2013/12/31 by Chris Orban
Mathematics · Physics and Astronomy · #Algorithm #Astrophysics #Baryon #Computer science #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Lambda #Mathematics #Particle physics #Perturbation (astronomy) #Perturbation theory (quantum mechanics) #Physics #Quantum mechanics #Scale (ratio) #Scientific Research and Discoveries #Spectral density #Statistical physics #Statistics #Theoretical physics #astro-ph.CO
paper · pdf · doi:10.1103/physrevd.90.023509
published as Phys. Rev. D 90, 023509 (2014) · 10 pages, 5 figures
arxiv created 2014/06/16 · openalex publication_date 2014/07/07 · arxiv updated 2014/07/16 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
In performing cosmological N-body simulations, it is widely appreciated that the growth of structure on the largest scales within a simulation box will be inhibited by the finite size of the simulation volume. Following ideas set forth by Seto Astrophys. J. 523, 24 (1999), this paper shows that standard (also known as one-loop) cosmological perturbation theory (SPT) [E. T. Vishniac, Mon. Not. R. Astron. Soc. 203, 345 (1983)] can be used to predict, in an approximate way, the deleterious effect of the box scale on the power spectrum of density fluctuations in simulation volumes. Alternatively, this approach can be used to quickly estimate post facto the effect of the box scale on power spectrum results from existing simulations. In this way SPT can help determine whether larger box sizes or other more-sophisticated methods are needed to achieve a particular level of precision for a given application (e.g. simulations to measure the nonlinear evolution of baryon acoustic oscillations). I focus on SPT in this paper and show that its predictions differ only by about a factor of 2 or less from the measured suppression inferred from both power law and \mathrm\ensuremathΛCDM N-body simulations. It should be possible to improve the accuracy of these predictions through using more-sophisticated perturbation theory models. An Appendix compares power spectrum measurements from the power law simulations at outputs where box-scale effects are minimal to perturbation theory models and previously published fitting functions. These power spectrum measurements are included with this paper to aid efforts to develop new perturbation theory models.