Skewness in large-scale structure and non-Gaussian initial conditions

Abstract

view Abstract Citations (71) References (21) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Skewness in Large-Scale Structure and Non-Gaussian Initial Conditions Fry, J. N. ; Scherrer, Robert J. Abstract We compute the skewness of the galaxy distribution arising from the nonlinear evolution of arbitrary non-Gaussian initial conditions to second order in perturbation theory including the effects of nonlinear biasing. The result contains a term identical to that for a Gaussian initial distribution plus terms which depend on the skewness and kurtosis of the initial conditions. The results are model dependent; we present calculations for several toy models. At late times, the leading contribution from initial skewness decays away relative to the other terms and becomes increasingly unimportant, but the contribution from initial kurtosis, previously overlooked, has the same time dependence as the Gaussian terms. Observations of a linear dependence of the normalized skewness on the rms density fluctuation therefore do not necessarily rule out initially non-Gaussian models. We also show that with non-Gaussian initial conditions the first correction to linear theory for the mean square density fluctuation is larger than for Gaussian models. Publication: The Astrophysical Journal Pub Date: July 1994 DOI: 10.1086/174300 Bibcode: 1994ApJ...429...36F Keywords: Boundary Value Problems; Galactic Clusters; Galactic Evolution; Skewness; Spatial Distribution; Boundary Conditions; Density Distribution; Fluctuation Theory; Nonlinear Evolution Equations; Nonlinear Systems; Astrophysics; COSMOLOGY: LARGE-SCALE STRUCTURE OF UNIVERSE; GALAXIES: CLUSTERING full text sources ADS |