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Related papers: Illumination Bodies in Projective Geometries

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We show that grafting any fixed hyperbolic surface defines a homeomorphism from the space of measured laminations to Teichmuller space, complementing a result of Scannell-Wolf on grafting by a fixed lamination. This result is used to study…

Differential Geometry · Mathematics 2014-11-11 David Dumas , Michael Wolf

Illumination of scenes is usually generated in computer graphics using polygonal meshes. In this paper, we present a geometric method using projections. Starting from an implicit polynomial equation of a surface in 3-D or a curve in 2-D, we…

Computational Geometry · Computer Science 2026-04-03 Michal Zamboj , Jakub Řada

We study the surface area of an ellipsoid in n-dimensional Euclidean space as the function of the lengths of their major semi-axes. We write down an explicit formula as an integral over the unit sphere, use the formula to derive convexity…

Metric Geometry · Mathematics 2007-05-23 Igor Rivin

When considered as submanifolds of Euclidean space, the Riemannian geometry of the round sphere and the Clifford torus may be formulated in terms of Poisson algebraic expressions involving the embedding coordinates, and a central object is…

Quantum Algebra · Mathematics 2015-06-16 Joakim Arnlind

This article belongs to the area of geometric tomography, which is the study of geometric properties of solids based on data about their sections and projections. We describe a new direction in geometric tomography where different…

Functional Analysis · Mathematics 2023-02-10 Apostolos Giannopoulos , Alexander Koldobsky , Artem Zvavitch

The discrete Laplacian on Euclidean triangulated surfaces is a well-established notion. We introduce discrete Laplacians on spherical and hyperbolic triangulated surfaces. On the one hand, our definitions are close to the Euclidean one in…

Metric Geometry · Mathematics 2025-07-25 Ivan Izmestiev , Wai Yeung Lam

Covering numbers of convex bodies based on homothetical copies and related illumination numbers are well-known in combinatorial geometry and, for example, related to Hadwiger's famous covering problem. Similar numbers can be defined by…

Metric Geometry · Mathematics 2013-08-06 Horst Martini , Christian Richter , Margarita Spirova

We investigate a duality relation between floating and illumination bodies. The definitions of these two bodies suggest that the polar of the floating body should be similar to the illumination body of the polar. We consider this question…

Metric Geometry · Mathematics 2017-09-11 Olaf Mordhorst , Elisabeth M. Werner

A method to generalize results from Riemannian Geometry to Finsler geometry is presented. We use the method to generalize several results that involve only metric conditions. Between them we show that the topology induced by the Finsler…

Differential Geometry · Mathematics 2010-09-23 Ricardo Gallego Torrome

We study the classification of smooth toroidal compactifications of nonuniform ball quotients in the sense of Kodaira and Enriques. Moreover, several results concerning the Riemannian and complex algebraic geometry of these spaces are…

Differential Geometry · Mathematics 2012-01-17 Luca Fabrizio Di Cerbo

We give a short and simple proof of Cauchy's surface area formula, which states that the average area of a projection of a convex body is equal to its surface area up to a multiplicative constant in the dimension.

Differential Geometry · Mathematics 2016-04-21 Emmanuel Tsukerman , Ellen Veomett

Cooper and Long generalised Epstein and Penner's Euclidean cell decomposition of cusped hyperbolic manifolds of finite volume to non-compact strictly convex projective manifolds of finite volume. We show that Weeks' algorithm to compute…

Geometric Topology · Mathematics 2015-12-08 Stephan Tillmann , Sampson Wong

The classical result of Cauchy's surface area formula states that the surface area of the boundary $\partial K=\Sigma$ of any $n$-dimensional convex body in the $n$-dimensional Euclidean space $\mathbb{R}^n$ can be obtained by the average…

Differential Geometry · Mathematics 2023-03-08 Yen-Chang Huang

In this paper, we introduce a new discretization of the Gaussian curvature on surfaces, which is defined as the quotient of the angle defect and the area of some dual cell of a weighted triangulation at the conic singularity. A discrete…

Differential Geometry · Mathematics 2023-09-12 Xu Xu , Chao Zheng

We give geometric interpretations of certain affine invariants of convex bodies. The affine invariants are the p-affine surface areas introduced by Lutwak. The geometric interpretations involve generalizations of the Santal\'o-bodies…

Metric Geometry · Mathematics 2009-09-25 Mathieu Meyer , Elisabeth Werner

We prove qualitative and quantitative results concerning the asymptotic density in dilates of centered convex bodies of the frequency vectors of orthogonal exponential bases and frames associated to bounded domains in Euclidean space.

Classical Analysis and ODEs · Mathematics 2007-05-23 Alex Iosevich , Mihail N. Kolountzakis

We consider a smooth Euclidean solid cone endowed with a smooth homogeneous density function used to weight Euclidean volume and hypersurface area. By assuming convexity of the cone and a curvature-dimension condition we prove that the…

Differential Geometry · Mathematics 2013-04-17 Antonio Cañete , César Rosales

For general varifolds in Euclidean space, we prove an isoperimetric inequality, adapt the basic theory of generalised weakly differentiable functions, and obtain several Sobolev type inequalities. We thereby intend to facilitate the use of…

Differential Geometry · Mathematics 2018-04-10 Ulrich Menne , Christian Scharrer

In Euclidean space, we investigate surfaces whose mean curvature $H$ satisfies the equation $H=\alpha\langle N,\mathbf{x}\rangle+\lambda$, where $N$ is the Gauss map, $\mathbf{x}$ is the position vector and $\alpha$ and $\lambda$ are two…

Differential Geometry · Mathematics 2020-05-18 Rafael López

We consider the mean curvature flow of compact convex surfaces in Euclidean $3$-space with free boundary lying on an arbitrary convex barrier surface with bounded geometry. When the initial surface is sufficiently convex, depending only on…

Analysis of PDEs · Mathematics 2020-01-07 Sven Hirsch , Martin Li