Discreteness Effects in Lambda Cold Dark Matter Simulations: A Wavelet-Statistical View

Abstract

The effects of particle discreteness in N-body simulations of Lambda Cold Dark Matter (LambdaCDM) 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 LambdaCDM simulations and analyse them using a large 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 epsilon ~ 2d, where "epsilon" is the force resolution and "d" is the interparticle distance. We clarify what such a condition means, and how to implement it in modern cosmological codes.

ApJ, in press. Minor changes to match the accepted version

References in corpus (9)

• The imprints of primordial non-gaussianities on large-scale structure: scale dependent bias and abundance of virialized objects
• Discreteness effects in simulations of Hot/Warm dark matter
• The fine-grained phase-space structure of Cold Dark Matter halos
• On the Structure of Dark Matter Halos at the Damping Scale of the Power Spectrum with and without Relict Velocities
• VINE -- A numerical code for simulating astrophysical systems using particles I: Description of the physics and the numerical methods
• Quantification of discreteness effects in cosmological N-body simulations: II. Evolution up to shell crossing
• Multi-scale morphology of the galaxy distribution
• Gravitational dynamics of an infinite shuffled lattice: early time evolution and universality of non-linear correlations
• The Distribution of Dark Matter in the Universe on Scales of 10^10 M_sun to 10^15 M_sun

Cited by in corpus (3)

• Towards quantitative control on discreteness error in the non-linear regime of cosmological N body simulations
• Particle Physics in the Sky and Astrophysics Underground: Connecting the Universe's Largest and Smallest Scales
• Comment on 'Discreteness Effects in Lambda Cold Dark Matter Simulations: A Wavelet-Statistical View' by Romeo et al