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Related papers: Genus statistics for structure formation with topo…

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As a statistical measure to quantify the topological structure of the large-scale structure in the universe, the genus number is calculated for a number of non-Gaussian distributions in which the density field is characterized by a…

Astrophysics · Physics 2009-10-28 Takahiko Matsubara , Jun'ichi Yokoyama

Good statistics for measuring large-scale structure in the Universe must be able to distinguish between different models of structure formation. In this paper, two and three dimensional ``counts in cell" statistics and a new ``discrete…

Astrophysics · Physics 2007-05-23 Robert H. Brandenberger , David M. Kaplan , Stephen A , Ramsey

The topology of weak lensing fields is studied using the 2-dimensional genus statistic. Simulated fields of the weak lensing convergence are used to focus on the effect of nonlinear gravitional evolution and to model the statistical errors…

Astrophysics · Physics 2009-10-31 Takahiko Matsubara , Bhuvnesh Jain

We probe gravitational clustering in N-body simulations using geometrical descriptors sensitive to `connectedness': the genus curve, percolation and shape statistics. We find that both genus and percolation curves provide complementary…

Astrophysics · Physics 2007-05-23 V. Sahni

We describe an implementation of the structure functions of Babul \& Starkman, in order to quantify the ``sheet-like'' nature of a distribution of matter. We test this statistic on a toy model describing cosmic string wakes, and show that…

Astrophysics · Physics 2015-06-24 James Robinson , Andreas Albrecht

Gaussian cosmological models, typified by the inflationary cold dark matter models, and non-Gaussian topological defect based cosmological models, such as the texture seeded model, differ in the origin of large-scale cosmic structures. In…

Astrophysics · Physics 2009-10-30 Renyue Cen

A new class of geometric statistics for analyzing galaxy catalogs is presented. Filament statistics quantify filamentarity and planarity in large scale structure in a manner consistent with catalog visualizations. These statistics are based…

Astrophysics · Physics 2015-06-24 Romeel Davé , Doug Hellinger , Joel Primack , Richard Nolthenius , Anatoly Klypin

We study topological properties of large scale structure in a set of scale free N-body simulations using the genus and percolation curves as topological characteristics. Our results show that as gravitational clustering advances, the…

Astrophysics · Physics 2009-10-28 Varun Sahni , B. S. Sathyaprakash , S. F. Shandarin

We measure the three-dimensional topology of large-scale structure in the Sloan Digital Sky Survey (SDSS). This allows the genus statistic to be measured with unprecedented statistical accuracy. The sample size is now sufficiently large to…

The statistical methods derived and described in this thesis provide new ways to elucidate the structural properties of text and other symbolic sequences. Generically, these methods allow detection of a difference in the frequency of a…

Computation and Language · Computer Science 2012-07-10 Ted Dunning

The genus statistics is studied using large $N$-body simulations for several cosmological models. We consider the effects of nonlinear gravitational evolution, smoothing the particle data in fully nonlinear regime, and the redshift-space…

Astrophysics · Physics 2009-10-28 Takahiko Matsubara , Yasushi Suto

We study the population profile in a simple discrete time model of population dynamics. Our model, which is closely related to certain ``bit-string'' models of evolution, incorporates competition for resources via a population dependent…

Statistical Mechanics · Physics 2009-10-31 Martin Howard , R. K. P. Zia

We examine genetic statistics used in the study of structured populations. In a 1999 paper, Wakeley observed that the coalescent process associated with the finite island model can be decomposed into a scattering phase and a collecting…

Populations and Evolution · Quantitative Biology 2008-11-11 Sivan Leviyang

A new class of geometric statistics for analyzing galaxy catalogs is presented. {\it Filament statistics} quantify filamentarity and planarity in large scale structure in a manner consistent with catalog visualizations. These statistics are…

Astrophysics · Physics 2007-05-23 Romeel Davé , Doug Hellinger , Richard Nolthenius , Joel Primack , Anatoly Klypin

Upon a consistent topological statistical theory the application of structural statistics requires a quantification of the proximity structure of model spaces. An important tool to study these structures are Pseudo-Riemannian metrices,…

Statistics Theory · Mathematics 2020-06-23 Patrick Michl

In the standard model for structure formation, bound objects originate from the gravitational collapse of small perturbations arising from quantum fluctuations with random phases. In other scenarios, based on defects, structures are seeded…

Astrophysics · Physics 2009-11-06 Licia Verde , Alan F. Heavens

Gaussian concentration graph models and covariance graph models are two classes of graphical models that are useful for uncovering latent dependence structures among multivariate variables. In the Bayesian literature, graphs are often…

Statistics Theory · Mathematics 2015-05-08 Hao Wang

Because biological processes can make different loci have different evolutionary histories, species tree estimation requires multiple loci from across the genome. While many processes can result in discord between gene trees and species…

Quantitative Methods · Quantitative Biology 2018-03-13 Md. Shamsuzzoha Bayzid , Siavash Mirarab , Bastien Boussau , Tandy Warnow

These lecture notes introduce the statistical analysis of continuous-time generative models built from Markov dynamics. We begin with the stochastic-calculus foundations of score-based diffusion models, including time reversal, score…

Statistics Theory · Mathematics 2026-04-27 Eddie Aamari , Arthur Stéphanovitch

Context. The main feature of the spatial large-scale galaxy distribution is an intricate network of galaxy filaments. Although many attempts have been made to quantify this network, there is no unique and satisfactory recipe for that yet.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 R. S. Stoica , V. J. Martinez , E. Saar
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