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Related papers: Mesoscopic Speckle

200 papers

Our statistical studies comprise the mean relative velocity and velocity correlation for pairs of galaxies as a function of separation, and a bulk flow analysis determined on spheres of $10 h^{-1}$ $Mpc$ radius. In order to test the…

Astrophysics · Physics 2009-10-30 Nelson Padilla , Manuel Merchán , Diego G. Lambas

We analyze a technique of obtaining turbulence power spectrum using spectral line data along the velocity coordinate, which we refer to as Velocity Coordinate Spectrum (VCS). We formalize geometrical aspects of observation through a single…

Astrophysics · Physics 2007-05-23 A. Chepurnov , A. Lazarian

We examine the empirical distribution of the eigenvalues and the eigenvectors of adjacency matrices of sparse regular random graphs. We find that when the degree sequence of the graph slowly increases to infinity with the number of…

Probability · Mathematics 2012-10-15 Ioana Dumitriu , Soumik Pal

The regular variation model for multivariate extremes decomposes the joint distribution of the extremes in polar coordinates in terms of the angles and the norm of the random vector as the product of two independent densities: the angular…

Methodology · Statistics 2025-08-08 Fernández-Durán , J. J. , Gregorio-Domínguez , M. M

The statistical distribution of the ratio of two normal random variables is characterized by its heavy-tailed nature and absence of finite moments. The shape of its density function is highly variable, capable of exhibiting unimodal or…

Probability · Mathematics 2023-11-07 Sheng Yang , Zhengtao Gui

Understanding the non-local pressure contributions and viscous effects on the small-scale statistics remains one of the central challenges in the study of homogeneous isotropic turbulence. Here we address this issue by studying the impact…

Fluid Dynamics · Physics 2014-09-03 Michael Wilczek , Charles Meneveau

We assemble a statistical set of global mass models for ~2,000 nearly spherical SDSS galaxies at a mean redshift of 0.12 based on their aperture velocity dispersions and newly derived luminosity profiles in conjunction with published…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Kyu-Hyun Chae , Mariangela Bernardi , Andrey V. Kravtsov

In this paper we test the results of a recent analytical study by Lazarian and Pogosyan, on the statistics of emissivity in velocity channel maps, in the case of realistic density and velocity fields obtained from numerical simulations of…

Astrophysics · Physics 2009-11-06 Alex Lazarian , Dmitri Pogosyan , Enrique Vazquez-Semadeni , Barbara Pichardo

We study stationary solutions to the continuity equation for weakly compressible flows. These describe non-equilibrium steady states of weakly dissipative dynamical systems. Compressibility is a singular perturbation that changes the steady…

Chaotic Dynamics · Physics 2010-09-14 Itzhak Fouxon

Measurements of the peculiar velocities of large samples of galaxies enable new tests of the standard cosmological model, including determination of the growth rate of cosmic structure that encodes gravitational physics. With the size of…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-19 Chris Blake , Ryan J. Turner

Stimulated by the need of describing useful notions related to information measures, we introduce the `pdf-related distributions'. These are defined in terms of transformation of absolutely continuous random variables through their own…

Probability · Mathematics 2024-05-02 Antonio Di Crescenzo , Luca Paolillo , Alfonso Suarez-Llorens

We examine statistical properties of a laser beam propagating in a turbulent medium. We prove that the intensity fluctuations at large propagation distances possess Gaussian probability density function and establish quantitative criteria…

Statistical Mechanics · Physics 2020-10-06 Igor Kolokolov , Vladimir Lebedev , Pavel M. Lushnikov

At low redshift, it is possible to combine spectroscopic information of galaxies with their luminosity or angular diameter distance to directly measure the projection of peculiar velocities (PV) along the line-of-sight. A PV survey probing…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-02 Mattia Pantiri , Matteo Foglieni , Enea Di Dio , Emanuele Castorina

Regular variation provides a convenient theoretical framework to study large events. In the multivariate setting, the dependence structure of the positive extremes is characterized by a measure - the spectral measure - defined on the…

Machine Learning · Statistics 2021-02-24 Meyer Nicolas , Olivier Wintenberger

Simulating a Gaussian process requires sampling from a high-dimensional Gaussian distribution, which scales cubically with the number of sample locations. Spectral methods address this challenge by exploiting the Fourier representation,…

Machine Learning · Statistics 2026-02-27 Arsalan Jawaid , Abdullah Karatas , Jörg Seewig

Analytic expressions for the statistics of peaks of random fields with weak non-Gaussianity are provided. Specifically, the abundance and spatial correlation of peaks are represented by formulas which can be evaluated only by virtually…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-04 Takahiko Matsubara

We discuss the probability distribution of relative speed $\Delta V$ of inertial particles suspended in a highly turbulent gas when the Stokes numbers, a dimensionless measure of their inertia, is large. We identify a mechanism giving rise…

Fluid Dynamics · Physics 2009-11-13 K. Gustavsson , B. Mehlig , M. Wilkinson , V. Uski

A new model for stock price fluctuations is proposed, based upon an analogy with the motion of tracers in Gaussian random fields, as used in turbulent dispersion models and in studies of transport in dynamically disordered media. Analytical…

Statistical Mechanics · Physics 2009-11-10 James P. Gleeson

We analyze the deviations from Maxwell-Boltzmann statistics found in recent experiments studying velocity distributions in two-dimensional granular gases driven into a non-equilibrium stationary state by a strong vertical vibration. We show…

Statistical Mechanics · Physics 2009-11-07 Alain Barrat , Emmanuel Trizac

This manuscript reports a stochastic dynamical scenario whose associated stationary probability density function is exactly a previously proposed one to adjust high-frequency traded volume distributions. This dynamical conjecture,…

Statistical Mechanics · Physics 2009-11-11 Silvio M. Duarte Queiros