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In non-linear scales, the matter density distribution is not Gaussian. Consequently, the widely used two-point correlation function is not adequate anymore to capture the matter density field's entire behaviour. Among all statistics beyond…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Mohammad Ansari Fard , Zahra Baghkhani , Laya Ghodsi , Sina Taamoli , Farbod Hassani , Shant Baghram

We report the development of a scalar quantization approach that helps build tables of decision and reconstruction levels for any probability density function (pdf). Several example pdf's are used for illustration: Uniform, Gaussian,…

Medical Physics · Physics 2016-09-08 C. Tannous

This paper addresses distributed learning of a complex object for multiple networked robots based on distributed optimization and kernel-based support vector machine. In order to overcome a fundamental limitation of polynomial kernels…

Robotics · Computer Science 2024-12-17 Toshiyuki Oshima , Junya Yamauchi , Tatsuya Ibuki , Michio Seto , Takeshi Hatanaka

Kendall's Similarity Shape Theory for constellations of points in the carrier space $\mathbb{R}^n$ was developed for use in Probability and Statistics. It was subsequently shown to reside within (Classical and Quantum) Mechanics'…

General Relativity and Quantum Cosmology · Physics 2018-03-30 Edward Anderson

A new family of distributions indexed by the class of matrix variate contoured elliptically distribution is proposed as an extension of some bimatrix variate distributions. The termed \emph{multimatrix variate distributions} open new…

Statistics Theory · Mathematics 2024-05-07 José A. Díaz-García , Francisco J. Caro-Lopera

Gaussian mixture model is very useful in many practical problems. Nevertheless, it cannot be directly generalized to non Euclidean spaces. To overcome this problem we present a spherical Gaussian-based clustering approach for partitioning…

Machine Learning · Computer Science 2017-05-08 Marek Śmieja , Jacek Tabor

We formulate and investigate a statistical inverse problem of a random tomographic nature, where a probability density function on $\mathbb{R}^3$ is to be recovered from observation of finitely many of its two-dimensional projections in…

Statistics Theory · Mathematics 2009-09-03 Victor M. Panaretos

For a general formulation of linearised hybrid inverse problems in impedance tomography, the qualitative properties of the solutions are analysed. Using an appropriate scalar pseudo-differential formulation, the problems are shown to permit…

Analysis of PDEs · Mathematics 2017-08-03 Guillaume Bal , Kristoffer Hoffmann , Kim Knudsen

In the context of complex algebraic varieties, the decomposition theorem for semi-small maps provides a decomposition of the direct image of the constant sheaf. In this work, we develop a decomposition theorem for branched coverings of…

Algebraic Topology · Mathematics 2026-03-02 Shahryar Ghaed Sharaf

In this paper, we derive new shape descriptors based on a directional characterization. The main idea is to study the behavior of the shape neighborhood under family of transformations. We obtain a description invariant with respect to…

Computer Vision and Pattern Recognition · Computer Science 2013-02-26 Xavier Descombes , Serguei Komech

We study spherically symmetric spacetimes for matter distributions with isotropic pressures. We generate new exact solutions to the Einstein field equations which also contains isotropic pressures. We develop an algorithm that produces a…

General Relativity and Quantum Cosmology · Physics 2014-12-23 S. Ngubelanga , S. D. Maharaj

We test the methods developed in previous papers for inferring the intrinsic shapes of elliptical galaxies, using simulated objects from N-body experiments. The shapes of individual objects are correctly reproduced to within the statistical…

Astrophysics · Physics 2009-10-31 T. S. Statler

This paper presents a new approach to the estimation of the deformation of an isotropic Gaussian random field on $\mathbb{R}^2$ based on dense observations of a single realization of the deformed random field. Under this framework we…

Statistics Theory · Mathematics 2008-12-18 Ethan B. Anderes , Michael L. Stein

We propose a principled way to define Gaussian process priors on various sets of unweighted graphs: directed or undirected, with or without loops. We endow each of these sets with a geometric structure, inducing the notions of closeness and…

Machine Learning · Statistics 2023-02-28 Viacheslav Borovitskiy , Mohammad Reza Karimi , Vignesh Ram Somnath , Andreas Krause

The problem of finding elliptical shapes in an image will be considered. We discuss the solution which uses cross-entropy clustering. The proposed method allows the search for ellipses with predefined sizes and position in the space.…

Computer Vision and Pattern Recognition · Computer Science 2015-12-09 Jacek Tabor , Krzysztof Misztal

Diffusion-driven patterns appear on curved surfaces in many settings, initiated by unstable modes of an underlying Laplacian operator. On a flat surface or perfect sphere, the patterns are degenerate, reflecting translational/rotational…

Soft Condensed Matter · Physics 2025-09-09 John R. Frank , Jemal Guven , Mehran Kardar , Leyna Shackleton

Many living and physical systems such as cell aggregates, tissues or bacterial colonies behave as unconventional systems of particles that are strongly constrained by volume exclusion and shape interactions. Understanding how these…

Quantitative Methods · Quantitative Biology 2026-05-20 Antoine Diez , Jean Feydy

Application of the noncommutative geometry to several physical models is considered.

General Relativity and Quantum Cosmology · Physics 2007-05-23 P. A. Saponov

We define and study graphs associated to hexagon decompositions of surfaces by curves and arcs. One of the variants is shown to be quasi-isometric to the pants graph, whereas the other variant is quasi-isometric to (a Cayley graph of) the…

Geometric Topology · Mathematics 2025-01-22 Funda Gültepe , Hugo Parlier

This paper serves as a preparation of work that focuses on extracting cosmological sectors from Loop Quantum Gravity. We start with studying the extraction of subsystems from classical systems. A classical Hamiltonian system can be reduced…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Tim Koslowski