English
Related papers

Related papers: On open flat sets in spaces with bipolar compariso…

200 papers

We prove a Bishop volume comparison theorem and a Laplacian comparison theorem for a natural sub-Riemannian structure defined on Sasakian manifolds. This generalizes the earlier work for the three dimensional case.

Differential Geometry · Mathematics 2013-10-23 Paul W. Y. Lee , Chengbo Li

We begin by showing that every real analytic orbifold has a real analytic Riemannian metric. It follows that every reduced real analytic orbifold can be expressed as a quotient of a real analytic manifold by a real analytic almost free…

Geometric Topology · Mathematics 2014-10-01 Marja Kankaanrinta

This note describes sharp Milnor--Wood inequalities for the Euler number of flat oriented vector bundles over closed Riemannian manifolds locally isometric to products of hyperbolic planes. One consequence is that such manifolds do not…

Geometric Topology · Mathematics 2008-04-15 Michelle Bucher , Tsachik Gelander

Let $(M,g)$ be an $n$-dimensional asymptotically flat Riemannian manifold with nonnegative scalar curvature that admits a noncompact area-minimizing hypersurface $\Sigma \subset M$. In the case where $n = 3$, O. Chodosh and the first-named…

Differential Geometry · Mathematics 2025-06-12 Michael Eichmair , Thomas Koerber

In this note, we investigate conformally flat submanifolds of Euclidean space with positive index of relative nullity. Let $M^n$ be a complete conformally flat manifold and let $f\colon M^n\to \R^m$ be an isometric immersion. We prove the…

Differential Geometry · Mathematics 2019-05-23 Christos-Raent Onti

We extend the Gallot-Tanno Theorem to closed pseudo-Riemannian manifolds. It is done by showing that if the cone over a manifold admits a parallel symmetric $(0,2)-$tensor then it is Riemannian. Applications of this result to the existence…

Differential Geometry · Mathematics 2012-02-15 Vladimir S. Matveev , Pierre Mounoud

We study the Bergman space interpolation problem of open Riemann surfaces obtained from a compact Riemann surface by removing a finite number of points. We equip such a surface with what we call an asymptotically flat conformal metric,…

Complex Variables · Mathematics 2015-08-11 Dror Varolin

Substatic Riemannian manifolds with minimal boundary arise naturally in General Relativity as spatial slices of static spacetimes satisfying the Null Energy Condition. Moreover, they constitute a vast generalization of nonnegative Ricci…

Differential Geometry · Mathematics 2023-07-28 Stefano Borghini , Mattia Fogagnolo

In this paper we prove sharp multipolar Hardy-type inequalities in the Riemannian $L^p-$setting for $p\geq 2$ using the method of super-solutions and fundamental results from comparison theory on manifolds, thus generalizing previous…

Analysis of PDEs · Mathematics 2025-03-07 Cristian Ciulică , Teodor Rugină

Herein we present open problems and survey examples and theorems concerning sequences of Riemannian manifolds with uniform lower bounds on scalar curvature and their limit spaces. Examples of Gromov and of Ilmanen which naturally ought to…

Metric Geometry · Mathematics 2017-12-01 Christina Sormani

In this paper, we show that for a sequence of orientable complete uniformly asymptotically flat $3$-manifolds $(M_i , g_i)$ with nonnegative scalar curvature and ADM mass $m(g_i)$ tending to zero, by subtracting some open subsets $Z_i$,…

Differential Geometry · Mathematics 2024-02-28 Conghan Dong

We continue our study on Hermitian manifolds that are {\em Bismut torsion parallel,} or {\em BTP} for brevity, which means that the Bismut connection has parallel torsion tensor. For $n\geq 3$, BTP metrics can be balanced (and…

Differential Geometry · Mathematics 2025-10-14 Quanting Zhao , Fangyang Zheng

We prove the following three results in Hamiltonian dynamics. 1. The Weinstein conjecture holds true for every displaceable hypersurface of contact type. 2. Every magnetic flow on a closed Riemannian manifold has contractible closed orbits…

Symplectic Geometry · Mathematics 2007-05-23 Urs Frauenfelder , Felix Schlenk

This article is the sequel to our previous paper [LS] dealing with the near-equality case of the Positive Mass Theorem. We study the near-equality case of the Penrose Inequality for the class of complete asymptotically flat rotationally…

Differential Geometry · Mathematics 2015-05-30 Dan A. Lee , Christina Sormani

We consider a closed Riemannian manifold $(M^n ,g)$ of dimension $n\geq 3$ and study positive solutions of the equation $-\Delta_g u + \lambda u = \lambda u^q$, with $\lambda >0$, $q>1$. If $M$ supports a proper isoparametric function with…

Differential Geometry · Mathematics 2019-05-24 Alejandro Betancourt de la Parra , Jurgen Julio-Batalla , Jimmy Petean

In this paper we provide new rigidity results for four-dimensional Riemannian manifolds and their twistor spaces.In particular, using the moving frame method, we prove that $\mathbb{CP}^3$ is the only twistor space whose Bochner tensor is…

Differential Geometry · Mathematics 2024-09-12 Giovanni Catino , Davide Dameno , Paolo Mastrolia

We study the property of spectral-tightness of Riemannian manifolds, which means that the bottom of the spectrum of the Laplacian separates the universal covering space from any other normal covering space of a Riemannian manifold. We prove…

Differential Geometry · Mathematics 2021-10-13 Panagiotis Polymerakis

In Theorem 1, we generalize the results of Szabo for Berwald metrics that are not necessary strictly convex: we show that for every Berwald metric F there always exists a Riemannian metric affine equivalent to F. As an application we show…

Differential Geometry · Mathematics 2011-08-22 Vladimir S. Matveev

We consider open discrete mappings of Riemannian manifolds that satisfy some modulus inequality. We investigate the possibility of a continuous extension of such mappings to an isolated point on the boundary. It is proved that, these…

Complex Variables · Mathematics 2023-09-28 V. S. Desyatka , E. A. Sevost'yanov

In this work we consider a question in the calculus of variations motivated by riemannian geometry, the isoperimetric problem. We show that solutions to the isoperimetric problem, close in the flat norm to a smooth submanifold, are…

Differential Geometry · Mathematics 2020-07-16 Stefano Nardulli