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Related papers: The Spherical Cap Discrepancy of HEALPix Points

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In this paper we show how response function corrections to shear measurements (e.g. as required by Metacalibration) propagate into cosmic shear power spectra. We investigate a 2-sphere pixel (also known as HEALpixel') correction and a…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-01 T. D. Kitching , N. Tessore , P. L. Taylor

We study a lattice point counting problem for spheres arising from the Heisenberg groups. In particular, we prove an upper bound on the number of points on and near large dilates of the unit spheres generated by the anisotropic norms…

Classical Analysis and ODEs · Mathematics 2022-05-05 Elizabeth Campolongo , Krystal Taylor

We give theorems that can be used to upper bound the densities of packings of different spherical caps in the unit sphere and of translates of different convex bodies in Euclidean space. These theorems extend the linear programming bounds…

Metric Geometry · Mathematics 2014-09-26 David de Laat , Fernando Mario de Oliveira Filho , Frank Vallentin

Segmentation, a useful/powerful technique in pattern recognition, is the process of identifying object outlines within images. There are a number of efficient algorithms for segmentation in Euclidean space that depend on the variational…

Computer Vision and Pattern Recognition · Computer Science 2019-11-12 Xiaohao Cai , Christopher G. R. Wallis , Jennifer Y. H. Chan , Jason D. McEwen

We study the $L^{\infty}$ discrepancy of point sets generated by determinantal point processes on all compact, connected two-point homogeneous spaces, namely spheres and projective spaces. Using concentration inequalities and variance…

Classical Analysis and ODEs · Mathematics 2026-05-22 Carlos Beltrán , Ujué Etayo , Giacomo Gigante , Pedro R. López-Gómez , Ryan W. Matzke

We study the spherical cap packing problem with a probabilistic approach. Such probabilistic considerations result in an asymptotic sharp universal uniform bound on the maximal inner product between any set of unit vectors and a…

Statistics Theory · Mathematics 2017-05-08 Kai Zhang

We present a comprehensive study of the regularity of the covariance matrix of a discretized field on the sphere. In a particular situation, the rank of the matrix depends on the number of pixels, the number of spherical harmonics, the…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-12 J. D. Bilbao-Ahedo , R. B. Barreiro , D. Herranz , P. Vielva , E. Martínez-González

We prove rigidity for hypersurfaces with boundary in the unit $(n+1)$-sphere with scalar curvature bounded below by $n(n-1)$. Under appropriate boundary conditions, the hypersurfaces are shown to be part of the equatorial spheres. The lower…

Differential Geometry · Mathematics 2016-12-28 Lan-Hsuan Huang , Damin Wu

The spherical ensemble is a well-studied determinantal process with a fixed number of points on the sphere. The points of this process correspond to the generalized eigenvalues of two appropriately chosen random matrices, mapped to the…

Probability · Mathematics 2014-07-23 Kasra Alishahi , Mohammadsadegh Zamani

We consider the problem of covering hypersphere by a set of spherical hypercaps. This sort of problem has numerous practical applications such as error correcting codes and reverse k-nearest neighbor problem. Using the reduction of non…

Computational Geometry · Computer Science 2015-03-19 Marko D. Petkovic , Dragoljub Pokrajac , Longin Jan Latecki

We study numerical integration on the unit sphere $\mathbb{S}^2 \subset \mathbb{R}^3$ using equal weight quadrature rules, where the weights are such that constant functions are integrated exactly. The quadrature points are constructed by…

Numerical Analysis · Mathematics 2014-02-17 Johann S. Brauchart , Josef Dick

We prove that the information complexity (i.e., the inverse) of the classical spherical cap $L_2$ discrepancy on the $d$-dimensional sphere $\mathbb{S}^d$ decreases with dimension $d$, indicating a ``blessing of dimensionality'' for the…

Numerical Analysis · Mathematics 2026-04-24 Johann S. Brauchart , Josef Dick , Friedrich Pillichshammer

This note treats several problems for the fractional perimeter or $s$-perimeter on the sphere. The spherical fractional isoperimetric inequality is established. It turns out that the equality cases are exactly the spherical caps.…

Functional Analysis · Mathematics 2020-12-01 Andreas Kreuml , Olaf Mordhorst

We introduce orthogonal ring patterns in the 2-sphere and in the hyperbolic plane, consisting of pairs of concentric circles, which generalize circle patterns. We show that their radii are described by a discrete integrable system. This is…

Metric Geometry · Mathematics 2024-10-14 Alexander I. Bobenko

Clean Hoag-like ring galaxies are often characterized by an old compact central component, a depleted gap, and a detached outer ring. We identify a boundary-supported radial-layering mechanism in a shell-deformed Kepler control model. A…

Astrophysics of Galaxies · Physics 2026-05-18 Yue Xu , Chenxi Sun , Jianwei Zhang

Non-spherical emulsion droplets can be stabilized by densely packed colloidal particles adsorbed at their surface. In order to understand the microstructure of these surface packings, the ordering of hard spheres on ellipsoidal surfaces is…

Soft Condensed Matter · Physics 2015-04-16 Christopher J. Burke , Badel L. Mbanga , Zengyi Wei , Patrick T. Spicer , Timothy J. Atherton

A celebrated result of Beck shows that for any set of $N$ points on $\mathbb{S}^d$ there always exists a spherical cap $B \subset \mathbb{S}^d$ such that number of points in the cap deviates from the expected value $\sigma(B) \cdot N$ by at…

Classical Analysis and ODEs · Mathematics 2023-09-13 Dmitriy Bilyk , Michelle Mastrianni , Stefan Steinerberger

In this work we present a study on the characterization of ordered and disordered hyperuniform point distributions on spherical surfaces. In spite of the extensive literature on disordered hyperuniform systems in Euclidean geometries, to…

Disordered Systems and Neural Networks · Physics 2019-08-14 Ariel G. Meyra , Guillermo J. Zarragoicoechea , Alberto. L. Maltz , Enrique Lomba , Salvatore Torquato

In this paper, we provide the upper bound and the lower bound of the sum of the number of spherical face-partition pair of simple spherical polytope $P$ with $p$ facets.

Metric Geometry · Mathematics 2024-12-06 Huhe Han

Satellites mapping the spatial variations of the gravitational or magnetic fields of the Earth or other planets ideally fly on polar orbits, uniformly covering the entire globe. Thus, potential fields on the sphere are usually expressed in…

Data Analysis, Statistics and Probability · Physics 2013-06-17 Frederik J. Simons , F. A. Dahlen