Oscar Agertz
Associate Professor / Senior university lecturer / Wallenberg Academy Fellow
Discreteness effects in ACDM simulations : A wavelet-statistical view
Author
Summary, in English
The effects of particle discreteness in N-body ACDM simulations are still an intensively debated issue. In this paper we explore such effects, taking into account the scatter caused by the randomness of the initial conditions and focusing on the statistical properties of the cosmological density field. For this purpose, we run large sets of ACDM simulations and analyze them using a wide variety of diagnostics, including new and powerful wavelet statistics. Among other facts, we point out (1) that dynamical evolution does not propagate discreteness noise up from the small scales at which it is introduced and (2) that one should aim to satisfy the condition ε ∼ 2d, where e is the force resolution and d is the inter-particle distance. We clarify what such a condition means and how to implement it in modern cosmological codes.
Publishing year
2008-10-10
Language
English
Pages
1-12
Publication/Series
Astrophysical Journal
Volume
686
Issue
1
Document type
Journal article
Publisher
American Astronomical Society
Keywords
- Cosmology: Miscellaneous
- Dark matter
- Lale structure of universe
- Methods: N-body simulations
- Methods: Numerical
- Methods: Statistical
Status
Published
ISBN/ISSN/Other
- ISSN: 0004-637X