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We study necessary conditions on the geometry and the topology of domains in $\mathbb{R}^2$ that support a positive solution to a classical overdetermined elliptic problem. The ideas and tools we use come from constant mean curvature…

Analysis of PDEs · Mathematics 2013-10-15 Antonio Ros , Pieralberto Sicbaldi

We list up to M\"obius equivalence all possible degrees and embedding dimensions of real surfaces that are covered by at least two pencils of circles, together with the number of such pencils. In addition, we classify incidences between the…

Algebraic Geometry · Mathematics 2024-09-16 Niels Lubbes

We investigate the behaviour of vertices and inflexions on 1-parameter families of curves on smooth surfaces in the 3-space, which include a singular member. In particular, we discuss the context where the curves evolve as sections of a…

Differential Geometry · Mathematics 2014-02-24 Andre Diatta , Peter J. Giblin

We generalize the Ruh-Vilms problem by characterizing the submanifolds in Euclidean spaces with proper biharmonic Gauss map and we construct examples of such hypersurfaces.

Differential Geometry · Mathematics 2008-09-09 A. Balmuş , S. Montaldo , C. Oniciuc

The isometric immersion of two-dimensional Riemannian manifold with negative Gauss curvature into the three-dimensional Euclidean space is considered through the Gauss-Codazzi equations for the first and second fundamental forms. The large…

Analysis of PDEs · Mathematics 2015-12-22 Wentao Cao , Feimin Huang , Dehua Wang

We give a complete classification of Riemannian and Lorentzian surfaces of arbitrary codimension in a pseudo-sphere whose pseudo-spherical Gauss maps are of 1-type or, in particular, harmonic. In some cases a concrete global classification…

Differential Geometry · Mathematics 2016-04-25 Burcu Bektaş , Joeri Van der Veken , Luc Vrancken

In this paper we develop an abstract theory for the Codazzi equation on surfaces, and use it as an analytic tool to derive new global results for surfaces in the space forms ${\bb R}^3$, ${\bb S}^3$ and ${\bb H}^3$. We give essentially…

Differential Geometry · Mathematics 2009-02-16 Juan A. Aledo , José M. Espinar , José A. Gálvez

A classification of 2-dimensional surfaces imbedded in spacetime is presented, according to the algebraic properties of their shape tensor. The classification has five levels, and provides among other things a refinement of the concepts of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 José M M Senovilla

Motivated by applications in robotics and computer vision, we study problems related to spatial reasoning of a 3D environment using sublevel sets of polynomials. These include: tightly containing a cloud of points (e.g., representing an…

Optimization and Control · Mathematics 2017-03-09 Amir Ali Ahmadi , Georgina Hall , Ameesh Makadia , Vikas Sindhwani

We introduce the embedded Nash problem allowing singularities in the ambient space, and solve it in the case of surfaces, generalizing \cite[Theorem 1.22]{BdlB}.

Algebraic Geometry · Mathematics 2025-01-09 Javier de la Bodega

This paper concerns the global theory of properly embedded spacelike surfaces in three-dimensional Minkowski space in relation to their Gaussian curvature. We prove that every regular domain which is not a wedge is uniquely foliated by…

Differential Geometry · Mathematics 2019-09-13 Francesco Bonsante , Andrea Seppi , Peter Smillie

This essay, an excerpt of the author's Ph.D. in Philosophy of mathematics (2012) thought of as being a companion to recent discoveries of new explicit Cartan geometry curvatures, analyzes how Gauss, after having devised the isometrically…

History and Overview · Mathematics 2014-02-06 Joel Merker

The work consists of solutions of metric problems for convex and finite subsets of geodesic spaces.

Metric Geometry · Mathematics 2010-11-30 Evgenii N. Sosov

At any point of a surface in the four-dimensional Euclidean space we consider the geometric configuration consisting of two figures: the tangent indicatrix, which is a conic in the tangent plane, and the normal curvature ellipse. We show…

Differential Geometry · Mathematics 2009-05-28 Georgi Ganchev , Velichka Milousheva

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 classify the self-similar solutions to a class of Weingarten curvature flow of connected compact convex hypersurfaces, isometrically immersed into space forms with non-positive curvature, and obtain a new characterization of a sphere in…

Differential Geometry · Mathematics 2009-05-07 Guanghan Li , Isabel Salavessa , Chuanxi Wu

One of the most important problems in Geometric Tomography is to establish properties of a given convex body if we know some properties over its sections or its projections. There are many interesting and deep results that provide…

Single-view point cloud completion aims to recover the full geometry of an object based on only limited observation, which is extremely hard due to the data sparsity and occlusion. The core challenge is to generate plausible geometries to…

Computer Vision and Pattern Recognition · Computer Science 2022-10-05 Bowen Zhang , Xi Zhao , He Wang , Ruizhen Hu

We show that every topological surface lamination of a 3-manifold M is isotopic to one with smoothly immersed leaves. This carries out a project proposed by Gabai in [Problems in foliations and laminations, AMS/IP Stud. Adv. Math. 2.2…

Geometric Topology · Mathematics 2014-10-01 Danny Calegari

Let $S$ be a complete flat surface, such as the Euclidean plane. We obtain direct characterizations of the connected components of the space of all curves on $S$ which start and end at given points in given directions, and whose curvatures…

Geometric Topology · Mathematics 2016-02-11 Nicolau C. Saldanha , Pedro Zühlke