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Related papers: A note on subsets of positive reach

200 papers

Motivated by questions of manifold learning, we study a sequence of random manifolds, generated by embedding a fixed, compact manifold $M$ into Euclidean spheres of increasing dimension via a sequence of Gaussian mappings. One of the…

Probability · Mathematics 2016-08-09 Robert J. Adler , Sunder Ram Krishnan , Jonathan E. Taylor , Shmuel Weinberger

We study some qualitative properties of ancient solutions of superlinear heat equations on a Riemannian manifold, with particular interest in positivity and constancy in space.

Analysis of PDEs · Mathematics 2020-05-22 Daniele Castorina , Carlo Mantegazza

The goal of this paper is to develop some aspects of the deformation theory of piecewise flat structures on surfaces and use this theory to construct new geometric structures on the moduli space of Riemann surfaces.

Differential Geometry · Mathematics 2008-04-22 Marc Troyanov

We address the question of finding global solutions of the Helmholtz equation that are positive in a given set. This question arises in inverse scattering for penetrable obstacles. In particular, we show that there are solutions that are…

Analysis of PDEs · Mathematics 2023-09-12 Pu-Zhao Kow , Mikko Salo , Henrik Shahgholian

We study the existence of extremal functions on compact Riemannian manifold wich is locally Euclidean .

Analysis of PDEs · Mathematics 2007-05-23 Moubinool Omarjee

A variant of the Archimedean Positivstellensatz is proved which is based on Archimedean semirings or quadratic modules of generating subalgebras. It allows one to obtain representations of strictly positive polynomials on compact…

Algebraic Geometry · Mathematics 2024-01-18 Konrad Schmüdgen

In this note we briefly review some recent results of the authors on the topological and geometrical properties of 3-cosymplectic manifolds.

Differential Geometry · Mathematics 2012-09-10 Beniamino Cappelletti Montano , Antonio De Nicola , Ivan Yudin

In this paper we consider structures of complex Poisson brackets on the space of smooth functions in a $n$-dimensional complex manifold generated by the $(1,1)$-form $d=\partial+\overline{\partial}$-closed and non-degenerate (with…

Differential Geometry · Mathematics 2023-07-25 Ibrahima Hamidine , ALi Mahamane Saminou

Categorial methods for generating new local algebras from old ones are presented. A direct proof of the differential structure of the prolongations of a manifold is proposed.

Category Theory · Mathematics 2007-09-05 Margherita Barile , Fiorella Barone , Wlodzimierz M. Tulczyjew

Rigidity results are obtained for Riemannian $d$-manifolds with $\sec \geqslant 1$ and spherical rank at least $d-2>0$. Conjecturally, all such manifolds are locally isometric to a round sphere or complex projective space with the…

Differential Geometry · Mathematics 2014-09-29 Benjamin Schmidt , Krishnan Shankar , Ralf Spatzier

In my talk I will discuss the following results which were obtained in joint work with Wilderich Tuschmann. 1. For any given numbers $m$, $C$ and $D$, the class of $m$-dimensional simply connected closed smooth manifolds with finite second…

Differential Geometry · Mathematics 2007-05-23 Anton Petrunin

In this paper, we investigate the relationship between positive definite functions on the unit sphere $\sph$ and on the Euclidean space $\RR^d$. For the dimension $d$ to be odd, a new technique is developed to establish the inheritance of…

Classical Analysis and ODEs · Mathematics 2026-04-14 Han Feng , Yan Ge

Assumptions on the reach are crucial for ensuring the correctness of many geometric and topological algorithms, including triangulation, manifold reconstruction and learning, homotopy reconstruction, and methods for estimating curvature or…

Computational Geometry · Computer Science 2024-12-09 Hana Dal Poz Kouřimská , André Lieutier , Mathijs Wintraecken

We describe recent work on positive descriptions of the structure constants of the cohomology of homogeneous spaces such as the Grassmannian, by degenerations and related methods. We give various extensions of these rules, some new and…

Algebraic Geometry · Mathematics 2007-05-23 Izzet Coskun , Ravi Vakil

A notion of general manifolds is introduced. It covers all usual manifolds in mathematics. Essentially, it is a way how to get a bigger 'fibration' over a site which locally coincides with a given one. An enrichment with generalized…

Category Theory · Mathematics 2007-05-23 G. V. Kondratiev

Representing graphs as sets of node embeddings in certain curved Riemannian manifolds has recently gained momentum in machine learning due to their desirable geometric inductive biases, e.g., hierarchical structures benefit from hyperbolic…

Machine Learning · Computer Science 2020-06-09 Calin Cruceru , Gary Bécigneul , Octavian-Eugen Ganea

This is a survey on recent developments on the Hausdorff dimension of projections and intersections for general subsets of Euclidean spaces, with an emphasis on estimates of the Hausdorff dimension of exceptional sets and on restricted…

Classical Analysis and ODEs · Mathematics 2018-01-03 Pertti Mattila

Discrete forms of the mean and directed curvature are constructed on piecewise flat manifolds, providing local curvature approximations for smooth manifolds embedded in both Euclidean and non-Euclidean spaces. The resulting expressions take…

Differential Geometry · Mathematics 2023-04-04 Rory Conboye

On a smooth asymptotically flat Riemannian manifold with non-compact boundary, we prove a positive mass theorem for metrics which are only continuous across a compact hypersurface. As an application, we obtain a positive mass theorem on…

Differential Geometry · Mathematics 2025-06-26 Sergio Almaraz , Shaodong Wang

This article is the introductory part of authors PhD thesis. The article presents a new coordinate invariant definition of quasiregular and quasiconformal mappings on Riemannian manifolds that generalizes the definition of quasiregular…

Differential Geometry · Mathematics 2014-08-12 Tony Liimatainen