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Bayesian estimation strategies represent the most fundamental formulation of the state estimation problem available, and apply readily to nonlinear systems with non-Gaussian uncertainties. The present paper introduces a novel method for…

Optimization and Control · Mathematics 2013-01-22 T R Bewley , A S Sharma

(Abridged) We discuss the probability distribution function (PDF) of column density resulting from density fields with lognormal PDFs, applicable to isothermal gas (e.g., probably molecular clouds). We suggest that a ``decorrelation…

Astrophysics · Physics 2009-11-06 Enrique Vazquez-Semadeni , Nieves Garcia

The large-scale structure in cosmology is highly non-Gaussian at late times and small length scales, making it difficult to describe analytically. Parameter inference, data reconstruction, and data generation tasks in cosmology are greatly…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-13 Adam Rouhiainen

We conduct numerical experiments to determine the density probability distribution function (PDF) produced in supersonic, isothermal, self-gravitating turbulence of the sort that is ubiquitous in star-forming molecular clouds. Our…

Astrophysics of Galaxies · Physics 2021-08-10 Shivan Khullar , Christoph Federrath , Mark R. Krumholz , Christopher D. Matzner

We study the statistical inference of the cosmological dark matter density field from non-Gaussian, non-linear and non-Poisson biased distributed tracers. We have implemented a Bayesian posterior sampling computer-code solving this problem…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-01 Metin Ata , Francisco-Shu Kitaura , Volker Müller

We revisit the derivation of the mass function and the bias of dark matter halos for non-Gaussian initial conditions. We use a steepest-descent approach to point out that exact results can be obtained for the high-mass tail of the halo mass…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 P. Valageas

Minkowski Functionals (MFs) are topological statistics that have become one of many standard tools used for investigating the statistical properties of cosmological random fields. They have found regular use in studies of departures from…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-20 Geraint Pratten , Dipak Munshi

First-order statistics of scattered light is described using the representation of probability density cloud which visualizes a two-dimensional distribution for complex amplitude. The geometric parameters of the cloud are studied in detail…

Instrumentation and Methods for Astrophysics · Physics 2017-08-02 Natalia Yaitskova

An analytic approximation to the mass function for gravitationally bound objects is presented. We base on the Zel'dovich approximation to extend the Press-Schechter formalism to a nonspherical dynamical model. A simple extrapolation of that…

Astrophysics · Physics 2009-10-30 Jounghun Lee , Sergei F. Shandarin

It is known that in gravitational instability scenarios the nonlinear dynamics induces non-Gaussian features in cosmological density fields that can be investigated with perturbation theory. Here, I derive the expression of the joint…

Astrophysics · Physics 2011-05-23 F. Bernardeau

We use a Press-Schechter-like calculation to study how the abundance of voids changes in models with non-Gaussian initial conditions. While a positive skewness increases the cluster abundance, a negative skewness does the same for the void…

Astrophysics · Physics 2009-11-13 Marc Kamionkowski , Licia Verde , Raul Jimenez

The mass density distribution of Newtonian self-gravitating systems is studied analytically in field theoretical method. Modeling the system as a fluid in hydrostatical equilibrium, we apply Schwinger's functional derivative on the average…

Astrophysics of Galaxies · Physics 2021-07-21 Yang Zhang , Qing Chen , Shuguang Wu

Non-Gaussian likelihoods, ubiquitous throughout cosmology, are a direct consequence of nonlinearities in the physical model. Their treatment requires Monte-Carlo Markov-chain or more advanced sampling methods for the determination of…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-24 Lennart Röver , Lea Carlotta Bartels , Björn Malte Schäfer

Structure formation provides a strong test of any cosmic acceleration model because a successful dark energy model must not inhibit {\black or overpredict} the development of observed large-scale structures. Traditional approaches to…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 C. Prescod-Weinstein , N. Afshordi

We present a non-perturbative calculation of the 1-point probability distribution function (PDF) for the spherically-averaged matter density field. The PDF is represented as a path integral and is evaluated using the saddle-point method. It…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-20 Mikhail M. Ivanov , Alexander A. Kaurov , Sergey Sibiryakov

The probability density function (PDF) of a global measure in a large class of highly correlated systems has been suggested to be of the same functional form. Here, we identify the analytical form of the PDF of one such measure, the order…

We calculate the higher order moments in a sequence of models where the initial density fluctuations are drawn from a chi^2_nu distribution with a power-law power spectrum. For large values of nu the distribution is approximately gaussian,…

Astrophysics · Physics 2009-10-31 Martin White

The shape of the probability distribution function (PDF) of molecular clouds is an important ingredient for modern theories of star formation and turbulence. Recently, several studies have pointed out observational difficulties with…

Astrophysics of Galaxies · Physics 2015-10-07 Blakesley Burkhart , Min-Young Lee , Claire Murray , Snezana Stanimirovic

Current tools for multivariate density estimation struggle when the density is concentrated near a nonlinear subspace or manifold. Most approaches require choice of a kernel, with the multivariate Gaussian by far the most commonly used.…

Methodology · Statistics 2021-10-07 Minerva Mukhopadhyay , Didong Li , David B Dunson

We derive the exact relationship, including all non-linearities, between real-space and redshift-space two-point statistics through the pairwise velocity distribution function. We show using numerical simulations that the pairwise velocity…

Astrophysics · Physics 2009-11-10 Roman Scoccimarro