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Guaranteeing that Fr\'echet means of object populations do not locally self-intersect or are thereby affected is a serious challenge for object representations because the objects' shape space typically includes elements corresponding to…

Methodology · Statistics 2025-01-03 Mohsen Taheri , Stephen M. Pizer , Jörn Schulz

We prove two weighted geometric inequalities that hold for strictly mean convex and star-shaped hypersurfaces in Euclidean space. The first one involves the weighted area and the area of the hypersurface and also the volume of the region…

Differential Geometry · Mathematics 2020-01-08 Frederico Girão , Diego Rodrigues

For a convex body on the Euclidean unit sphere the spherical convex floating body is introduced. The asymptotic behavior of the volume difference of a spherical convex body and its spherical floating body is investigated. This gives rise to…

Differential Geometry · Mathematics 2014-12-01 Florian Besau , Elisabeth Werner

This paper introduces a new analytical method for the determination of the coverage area modeling the Earth as an oblate ellipsoid of rotation. Starting from the knowledge of the satellite's position vector and the direction of the…

Space Physics · Physics 2019-07-01 Marco Nugnes , Camilla Colombo , Massimo Tipaldi

We give an estimate of the mean curvature of a complete submanifold lying inside a closed cylinder $B(r)\times\R^{\ell}$ in a product Riemannian manifold $N^{n-\ell}\times\R^{\ell}$. It follows that a complete hypersurface of given constant…

Differential Geometry · Mathematics 2009-10-24 L. J. Alias , G. Pacelli Bessa , M. Dajczer

We will develop simple relations between the arc-lengths of a pair of geodesics that share common end-points. The two geodesics differ only by the requirement that one is constrained to lie in a subspace of the parent manifold. We will…

Differential Geometry · Mathematics 2015-12-14 Leo Brewin

We prove area bounds for planar convex bodies in terms of their number of interior integral points and their lattice width data. As an application, we obtain sharp area bounds for rational polygons with a fixed number of interior integral…

Metric Geometry · Mathematics 2025-07-03 Martin Bohnert

Ellipse and ellipsoid fitting has been extensively researched and widely applied. Although traditional fitting methods provide accurate estimation of ellipse parameters in the low-noise case, their performance is compromised when the noise…

Methodology · Statistics 2009-12-10 Jieqi Yu , Sanjeev R. Kulkarni , H. Vincent Poor

We suggest a set of morphological measures that we believe can help in quantifying the shapes of two-dimensional cosmological images such as galaxies, clusters, and superclusters of galaxies. The method employs non-parametric morphological…

Astrophysics · Physics 2009-07-30 Nurur Rahman , Sergei F. Shandarin

In this work we bring together tools and ideology from two different fields, Symplectic Geometry and Asymptotic Geometric Analysis, to arrive at some new results. Our main result is a dimension-independent bound for the symplectic capacity…

Symplectic Geometry · Mathematics 2007-05-23 Shiri Artstein-Avidan , Vitali D. Milman , Yaron Ostrover

We introduce a family of symmetric convex bodies called generalized ellipsoids of degree $d$ (GE-$d$s), with ellipsoids corresponding to the case of $d=0$. Generalized ellipsoids (GEs) retain many geometric, algebraic, and algorithmic…

Optimization and Control · Mathematics 2025-07-01 Amir Ali Ahmadi , Abraar Chaudhry , Cemil Dibek

We extend the notion of illumination bodies to Riemannian spaces of constant curvature and to projective Finsler geometries. We prove that the derivative of their volume defines a notion of surface area for convex bodies in these settings,…

Metric Geometry · Mathematics 2026-05-26 Rotem Assouline , Florian Besau , Elisabeth M. Werner

We study hypersurfaces with fractional mean curvature in N-dimensional Euclidean space. These hypersurfaces are critical points of the fractional perimeter under a volume constraint. We use local inversion arguments to prove existence of…

Analysis of PDEs · Mathematics 2018-04-06 Ignace Aristide Minlend , Alassane Niang , El Hadji Abdoulaye Thiam

We study surfaces in Euclidean space constructed by the sum of two curves or that are graphs of the product of two functions. We consider the problem to determine all these surfaces with constant Gauss curvature. We extend the results to…

Differential Geometry · Mathematics 2014-10-10 Rafael López , Marilena Moruz

This paper deals with the question of how to calculate the volume of a body in the three-dimensional Euclidean space when it is cut into slices perpendicular to a given curve. The answer is provided by a formula that can be considered as a…

Metric Geometry · Mathematics 2025-01-14 Harald Schmid

We study surfaces with a constant ratio of principal curvatures in Euclidean and simply isotropic geometries and characterize rotational, channel, ruled, helical, and translational surfaces of this kind under some technical restrictions…

Differential Geometry · Mathematics 2025-10-17 Khusrav Yorov , Mikhail Skopenkov , Helmut Pottmann

In this paper, based on the theory of surfaces in the four-dimensional Euclidean space which generalizes the theory of surfaces in three-dimensional Euclidean space, beside other results, we will give a characterization of points on…

Differential Geometry · Mathematics 2013-10-24 Azam Etemad Dehkordy

Given an $m$-dimensional closed connected Riemannian manifold $M$ smoothly isometrically immersed in an $n$-dimensional Riemannian manifold $N$, we estimate the diameter of $M$ in terms of its mean curvature field integral under some…

Differential Geometry · Mathematics 2010-10-21 Jia-Yong Wu , Yu Zheng

For a Riemannian manifold $M^{n+1}$ and a compact domain $\Omega \subset M^{n+1}$ bounded by a hypersurface $\partial \Omega$ with normal curvature bounded below, estimates are obtained in terms of the distance from $O$ to $\partial \Omega$…

Differential Geometry · Mathematics 2015-06-12 Alexander Borisenko , Kostiantyn Drach

Let B denote a three-dimensional body of rotation, with respect to one coordinate axis, whose boundary is sufficiently smooth and of bounded nonzero Gaussian curvature throughout, except for the two boundary points on the axis of rotation,…

Number Theory · Mathematics 2015-06-26 W. G. Nowak