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We propose nonparametric estimators for the second-order central moments of possibly anisotropic spherical random fields, within a functional data analysis context. We consider a measurement framework where each random field among an…

Statistics Theory · Mathematics 2022-06-28 Alessia Caponera , Julien Fageot , Matthieu Simeoni , Victor M. Panaretos

We consider the problem of a sphere rolling of a curved surface and solve it by mapping it to the precession of a spin 1/2 in a magnetic field of variable magnitude and direction. The mapping can be of pedagogical use in discussing both…

Classical Physics · Physics 2009-06-17 Alberto G. Rojo , Anthony M. Bloch

We prove a topological rigidity theorem for closed hypersurfaces of the Euclidean sphere and of an elliptic space form. It asserts that, under a lower bound hypothesis on the absolute value of the principal curvatures, the hypersurface is…

Differential Geometry · Mathematics 2018-09-28 Eduardo Longa , Jaime Ripoll

We show that for elliptic parametric functionals whose Wulff shape is smooth and has strictly positive curvature, any surface with constant anisotropic mean curvature which is a topological sphere is a rescaling of the Wulff shape.

Differential Geometry · Mathematics 2009-09-14 Miyuki Koiso , Bennett Palmer

We prove $\epsilon$-closeness of hypersurfaces to a sphere in Euclidean space under the assumption that the traceless second fundamental form is $\delta$-small compared to the mean curvature. We give the explicit dependence of $\delta$ on…

Differential Geometry · Mathematics 2015-07-08 Julian Scheuer

Based on the observation that the exterior space-times of Schwarzschild-type solutions allow two symmetric slicings, a static spherically symmetric one and a timelike homogeneous one, modifications of gravitational dynamics suggested by…

General Relativity and Quantum Cosmology · Physics 2020-08-11 Martin Bojowald

We provide an elementary derivation of an orthogonal coordinate system for boundary layers around evolving smooth surfaces and curves based on the signed-distance function. We go beyond previous works on the signed-distance function and…

Mathematical Physics · Physics 2023-10-27 Eric W. Hester , Geoffrey M. Vasil

Calculating by analytical theory the deformation of finite-sized elastic bodies in response to internally applied forces is a challenge. Here, we derive explicit analytical expressions for the amplitudes of modes of surface deformation of a…

Soft Condensed Matter · Physics 2024-07-15 Lukas Fischer , Andreas M. Menzel

Using 1000 ray-tracing simulations for a {\Lambda}-dominated cold dark model in Sato et al. (2009), we study the covariance matrix of cosmic shear correlation functions, which is the standard statistics used in the previous measurements.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Masanori Sato , Masahiro Takada , Takashi Hamana , Takahiko Matsubara

A new formalism is presented for analytically obtaining the probability density function, \( P_{n}(s) \), for the distance between two random points in an \( n \)-dimensional sphere of radius \( R \). Our formalism allows \( P_{n}(s) \) to…

Mathematical Physics · Physics 2007-05-23 Shu-Ju Tu , Ephraim Fischbach

The space-time geometry is considered to be a physical geometry, i.e. a geometry described completely by the world function. All geometrical concepts and geometric objects are taken from the proper Euclidean geometry. They are expressed via…

General Physics · Physics 2007-05-23 Yuri A. Rylov

Analyzing the covariance structure of data is a fundamental task of statistics. While this task is simple for low-dimensional observations, it becomes challenging for more intricate objects, such as multivariate functions. Here, the…

Methodology · Statistics 2023-01-12 Holger Dette , Gauthier Dierickx , Tim Kutta

The validation of global climate models is crucial to ensure the accuracy and efficacy of model output. We introduce the spherical convolutional Wasserstein distance to more comprehensively measure differences between climate models and…

Applications · Statistics 2024-02-05 Robert C. Garrett , Trevor Harris , Bo Li , Zhuo Wang

In this paper, we characterize round spheres in the Euclidean space under some suitable conditions on the r-mean curvature.

Differential Geometry · Mathematics 2020-12-18 Wagner Oliveira Costa-Filho

We consider a class of overdetermined problems in rotationally symmetric spaces, which reduce to the classical Serrin's overdetermined problem in the case of the Euclidean space. We prove some general integral identities for rotationally…

Analysis of PDEs · Mathematics 2016-10-31 Giulio Ciraolo , Luigi Vezzoni

The problem of measuring an unbounded system attribute near a singularity has been discussed. Lenses have been introduced as formal objects to study increasingly precise measurements around the singularity and a specific family of lenses…

General Mathematics · Mathematics 2020-07-13 Swagatam Sen

We study the spherical slice transform which assigns to a function on the $n$-dimensional unit sphere the integrals of that function over cross-sections of the sphere by $k$-dimensional affine planes passing through the north pole. These…

Functional Analysis · Mathematics 2021-08-03 Boris Rubin

A key problem in the attempt to quantize the gravitational field is the choice of boundary conditions. These are mixed, in that spatial and normal components of metric perturbations obey different sets of boundary conditions. In the…

High Energy Physics - Theory · Physics 2007-05-23 Ivan G. Avramidi , Giampiero Esposito

Spatial confounding is a fundamental issue in spatial regression models which arises because spatial random effects, included to approximate unmeasured spatial variation, are typically not independent of covariates in the model. This can…

Methodology · Statistics 2025-07-15 Emiko Dupont , Isa Marques , Thomas Kneib

Nonuniform tubular neighborhoods of curves in Euclidean n-space are studied by using weighted distance functions and generalizing the normal exponential map. Different notions of injectivity radii are introduced to investigate singular but…

Geometric Topology · Mathematics 2008-08-27 Oguz C. Durumeric