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We investigate the evolution of the skewness of the distribution of density fluctuations in CDM models with both Gaussian and non--Gaussian initial fluctuations. We show that the method proposed by Coles \& Frenk (1991), which uses the…

Astrophysics · Physics 2015-06-24 P. Coles , L. Moscardini , F. Lucchin , S. Matarrese , A. Messina

In this note, we give an overview of some results obtained in [3]. This latter work is devoted to the study of the one-dimensional nonlinear Schr{\"o}dinger equation with random initial conditions. Namely, we describe the nonlinear…

Analysis of PDEs · Mathematics 2024-04-05 Laurent Thomann , Nicolas Burq

In the environmental modeling field, the exploratory analysis of responses often exhibits spatial correlation as well as some non-Gaussian attributes such as skewness and/or heavy-tailedness. Consequently, we propose a general spatial model…

Statistics Theory · Mathematics 2019-07-25 Behzad Mahmoudian

Large-scale structures, observed today, are generally believed to have grown from random, small-amplitude inhomogeneities, present in the early Universe. We investigate how gravitational instability drives the distribution of these…

Astrophysics · Physics 2009-10-22 R. Juszkiewicz , F. R. Bouchet , S. Colombi

We compute the skewness $t_3$ and the corresponding hierarchical amplitude $T_3$ of the divergence of the velocity field for arbitrary non-Gaussian initial conditions. We find that $T_3$ qualitatively resembles the corresponding…

Astrophysics · Physics 2015-06-24 Zacharias A. M. Protogeros , Robert J. Scherrer

We calculate the kurtosis of a large-scale density field which has undergone weakly non-linear gravitational evolution from arbitrary non-Gaussian initial conditions. It is well known that the weakly evolved {\twelveit skewness} is equal to…

Astrophysics · Physics 2015-06-24 Michał J. Chodorowski , François R. Bouchet

We investigate the relative sensitivities of several tests for deviations from Gaussianity in the primordial distribution of density perturbations. We consider models for non-Gaussianity that mimic that which comes from inflation as well as…

Astrophysics · Physics 2009-10-31 Licia Verde , Raul Jimenez , Marc Kamionkowski , Sabino Matarrese

We use the spherical evolution approximation to investigate nonlinear evolution from the non-Gaussian initial conditions characteristic of the local f_nl model. We provide an analytic formula for the nonlinearly evolved probability…

Astrophysics · Physics 2009-11-13 Tsz Yan Lam , Ravi K. Sheth

Because of its mathematical tractability, the Gaussian mixture model holds a special place in the literature for clustering and classification. For all its benefits, however, the Gaussian mixture model poses problems when the data is skewed…

Applications · Statistics 2020-11-19 Michael P. B. Gallaugher , Paul D. McNicholas , Volodymyr Melnykov , Xuwen Zhu

We explore the possibility of putting constraints on dark energy models with statistical property of large scale structure in the non-linear region. In particular, we investigate the $w$ dependence of non-Gaussianity of the smoothed density…

Astrophysics · Physics 2010-10-27 Takayuki Tatekawa , Shuntaro Mizuno

Bouchet et al. (1992) showed that in an open or closed Universe with only pressureless matter, gravitational instability from Gaussian initial conditions induces a normalized skewness, $S_3 \equiv \VEV{\delta^3} \VEV{\delta^2}^{-2}$, that…

Astrophysics · Physics 2009-10-30 M. Kamionkowski , A. Buchalter

When the equations that govern the dynamics of a random field are nonlinear, the field can develop with time non-Gaussian statistics even if its initial condition is Gaussian. Here, we provide a general framework for calculating the effect…

Statistical Mechanics · Physics 2013-03-14 T. H. Beuman , A. M. Turner , V. Vitelli

Skewness and non-Gaussian behavior are essential features of the distribution of short-scale velocity increments in isotropic turbulent flows. Yet, although the skewness has been generally linked to time-reversal symmetry breaking and…

The observed abundance of high-redshift galaxies and clusters contains precious information about the properties of the initial perturbations. We present a method to compute analytically the number density of objects as a function of mass…

Astrophysics · Physics 2011-05-05 Sabino Matarrese , Licia Verde , Raul Jimenez

Following the discovery of the CMB, the hot big-bang model has become the standard cosmological model. In this theory, small primordial fluctuations are subsequently amplified by gravity to form the large-scale structure seen today.…

Astrophysics · Physics 2015-06-24 Licia Verde

We investigate the impact of non-Gaussian scatter in the cluster mass-observable scaling relation on the mass and redshift distribution of clusters detected by wide area surveys. We parameterize non-Gaussian scatter by incorporating the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Laurie D. Shaw , Gilbert P. Holder , Jonathan Dudley

It has long been known how to analytically relate the clustering properties of the collapsed structures (halos) to those of the underlying dark matter distribution for Gaussian initial conditions. Here we apply the same approach to…

Astrophysics · Physics 2010-11-11 Sabino Matarrese , Licia Verde

Non-Gaussianity indicates complex dynamics related to extreme events or significant outliers. However, the correlation between non-Gaussianity and the dynamics of heterogeneous environments in anomalous diffusion remains uncertain. Inspired…

Soft Condensed Matter · Physics 2023-11-22 Haolan Xu , Xu Zheng , Xinghua Shi

The non-Gaussian distribution of primordial perturbations has the potential to reveal the physical processes at work in the very early Universe. Local models provide a well-defined class of non-Gaussian distributions that arise naturally…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 David Wands

Noise is an unavoidable part of most measurements which can hinder a correct interpretation of the data. Uncertainties propagate in the data analysis and can lead to biased results even in basic descriptive statistics such as the central…

Instrumentation and Methods for Astrophysics · Physics 2023-11-27 Lorenzo Rimoldini
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