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In a system with long-ranged correlations, the behavior of correlation functions is sensitive to the presence of a boundary. We show that surface deformations strongly modify this behavior as compared to a flat surface. The modified near…

Statistical Mechanics · Physics 2009-11-07 Andreas Hanke , Mehran Kardar

This paper defines a distance function that measures the dissimilarity between planar geometric figures formed with straight lines. This function can in turn be used in partial matching of different geometric figures. For a given pair of…

Computer Vision and Pattern Recognition · Computer Science 2016-12-06 Apoorva Honnegowda Roopa , Shrisha Rao

In practical purposes for some geometrical problems in computer science we have as information the coordinates of some finite points in surface instead of the whole body of a surface. The problem arised here is: "How to define a distance…

Discrete Mathematics · Computer Science 2012-03-29 Hajar Ghahremani Gol , Asadollah Razavi , Farzad Didehva

A recent paper promises new constructions that may make it possible to achieve covariance in spherically symmetric models of loop quantum gravity. This claim is contrary to the discovery of several stubborn obstacles to covariance uncovered…

General Relativity and Quantum Cosmology · Physics 2023-01-05 Martin Bojowald

The well-known spatial sign covariance matrix (SSCM) carries out a radial transform which moves all data points to a sphere, followed by computing the classical covariance matrix of the transformed data. Its popularity stems from its…

Methodology · Statistics 2021-01-13 Jakob Raymaekers , Peter J. Rousseeuw

We study nonparametric covariance function estimation for functional data observed with noise at discrete locations on a $d$-dimensional domain. Estimating the covariance function from discretely observed data is a challenging nonparametric…

Statistics Theory · Mathematics 2026-03-25 Yoshikazu Terada , Atsutomo Yara

Unmeasured, spatially-structured factors can confound associations between spatial environmental exposures and health outcomes. Adding flexible splines to a regression model is a simple approach for spatial confounding adjustment, but the…

Applications · Statistics 2020-06-22 Joshua P. Keller , Adam A. Szpiro

This paper describes a novel framework for computing geodesic paths in shape spaces of spherical surfaces under an elastic Riemannian metric. The novelty lies in defining this Riemannian metric directly on the quotient (shape) space, rather…

Differential Geometry · Mathematics 2016-11-17 Alice Barbara Tumpach , Hassen Drira , Mohamed Daoudi , Anuj Srivastava

Isotropic Gaussian random fields on the sphere are characterized by Karhunen-Lo\`{e}ve expansions with respect to the spherical harmonic functions and the angular power spectrum. The smoothness of the covariance is connected to the decay of…

Probability · Mathematics 2015-10-26 Annika Lang , Christoph Schwab

Vector displacements expressed in spherical coordinates are proposed. They correspond to electromagnetic fields in vacuum that globally rotate about an axis and display many circular patterns on the surface of a sphere. The fields basically…

Classical Physics · Physics 2021-06-11 Daniele Funaro

Data uniformity is a concept associated with several semantic data characteristics such as lack of features, correlation and sample bias. This article introduces a novel measure to assess data uniformity and detect uniform pointsets on…

Computational Geometry · Computer Science 2020-04-14 Panagiotis Sidiropoulos

A notorious problem in mathematics and physics is to create a solvable model for random sequential adsorption of non-overlapping congruent spheres in the $d$-dimensional Euclidean space with $d\geq 2$. Spheres arrive sequentially at…

Probability · Mathematics 2019-01-25 Souvik Dhara , Johan S. H. van Leeuwaarden , Debankur Mukherjee

The likelihood function for cosmological parameters, given by e.g. weak lensing shear measurements, depends on contributions to the covariance induced by the nonlinear evolution of the cosmic web. As nonlinear clustering to date has only…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-26 Robert Reischke , Alina Kiessling , Björn Malte Schäfer

Numerical simulations of the dynamics of an elastic collision between a rigid sphere and an elastic half-space are carried out. We assume an Amontons-Coulomb frictional force with a fixed coefficient of friction between the contacting…

Soft Condensed Matter · Physics 2017-08-30 I. A. Lyashenko , E. Willert , V. L. Popov

Natural objects can be subject to various transformations yet still preserve properties that we refer to as invariants. Here, we use definitions of affine invariant arclength for surfaces in R^3 in order to extend the set of existing…

Computer Vision and Pattern Recognition · Computer Science 2010-12-30 Dan Raviv , Alexander M. Bronstein , Michael M. Bronstein , Ron Kimmel , Nir Sochen

We covariantize calculations over the manifold of phase space, establishing Stokes' theorem for differential cross sections and providing new definitions of familiar observable properties like infrared and collinear safety. Through the…

High Energy Physics - Phenomenology · Physics 2020-11-25 Andrew J. Larkoski , Tom Melia

We establish a uniformization result for metric surfaces - metric spaces that are topological surfaces with locally finite Hausdorff 2-measure. Using the geometric definition of quasiconformality, we show that a metric surface that can be…

Complex Variables · Mathematics 2019-09-20 Toni Ikonen

Spatial stochastic processes that are modeled over the entire Earth's surface require statistical approaches that directly consider the spherical domain. Here, we extend the notion of intrinsic random functions (IRF) to model non-stationary…

Statistics Theory · Mathematics 2016-06-08 Chunfeng Huang , Haimeng Zhang , Scott M. Robeson , Jacob Shields

A spherical conical metric $g$ on a surface $\Sigma$ is a metric of constant curvature $1$ with finitely many isolated conical singularities. The uniformization problem for such metrics remains largely open when at least one of the cone…

Differential Geometry · Mathematics 2021-04-22 Mikhail Karpukhin , Xuwen Zhu

We derive explicit expressions for a family of radially symmetric, non-differentiable, Spartan covariance functions in $\mathbb{R}^2$ that involve the modified Bessel function of the second kind. In addition to the characteristic length and…

Statistics Theory · Mathematics 2015-02-03 Dionissios T. Hristopulos