English

The Mildly Non-Linear Regime of Structure Formation

Cosmology and Nongalactic Astrophysics 2015-05-30 v2

Abstract

We present a simple physically motivated picture for the mildly non-linear regime of structure formation, which captures the effects of the bulk flows. We apply this picture to develop a method to significantly reduce the sample variance in cosmological N-body simulations at the scales relevant to the Baryon Acoustic Oscillations (BAO). The results presented in this paper will allow for a speed-up of an order of magnitude (or more) in the scanning of the cosmological parameter space using N-body simulations for studies which require a good handle of the mildly non-linear regime, such as those targeting the BAO. Using this physical picture we develop a simple formula, which allows for the rapid calculation of the mildly non-linear matter power spectrum to percent level accuracy, and for robust estimation of the BAO scale.

Keywords

Cite

@article{arxiv.1109.4939,
  title  = {The Mildly Non-Linear Regime of Structure Formation},
  author = {Svetlin Tassev and Matias Zaldarriaga},
  journal= {arXiv preprint arXiv:1109.4939},
  year   = {2015}
}

Comments

25 pages, 13 figures; accepted in JCAP; fixed irrelevant factor in equation; added a note on our analytical result