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Related papers: A generalized sphere theorem and its applications

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We investigate the effect of the average scalar curvature on the conjugate radius, average area of the geodesic spheres, average volume of the metric balls and the total volume of a closed Riemannian manifold $N$ (or more generally $N$ with…

Differential Geometry · Mathematics 2022-09-02 Kwok-Kun Kwong

We generalize the classical de Rham decomposition theorem for Riemannian manifolds to the setting of geodesic metric spaces of finite dimension.

Metric Geometry · Mathematics 2007-05-23 Thomas Foertsch , Alexander Lytchak

We present conditions on the Ricci curvature for complete, oriented, minimal submanifolds of Euclidean space, as well as the standard unit sphere, when the Gauss maps are bounded embeddings.

Differential Geometry · Mathematics 2009-09-15 Richard Atkins

In this paper we give bounds for the first eigenvalue of the conformal Laplacian and the Yamabe invariant of a compact Riemannian manifold, by using conditions on the Ricci curvature and the diameter and deduce certain conditions on the…

Differential Geometry · Mathematics 2008-04-23 Salem Eljazi , Najoua Gamara , Habiba Guemri

We use a construction which we call generalized cylinders to give a new proof of the fundamental theorem of hypersurface theory. It has the advantage of being very simple and the result directly extends to semi-Riemannian manifolds and to…

Differential Geometry · Mathematics 2019-01-08 Christian Baer , Paul Gauduchon , Andrei Moroianu

This work proves certain general orbifold compactness results for spaces of Riemannian metrics, generalizing earlier results along these lines for Einstein metrics or metrics with bounded Ricci curvature. This is then applied to prove such…

Differential Geometry · Mathematics 2007-05-23 Michael T. Anderson

We prove a compactness theorem for metrics with Bounded Integral Curvature on a fixed closed surface $\Sigma$. As a corollary, we obtain a compactification of the space of Riemannian metrics with conical singularities, where an accumulation…

Differential Geometry · Mathematics 2016-10-20 Clément Debin

A classical theorem of Bochner asserts that the isometry group of a compact Riemannian manifold with negative Ricci curvature is finite. In this paper we give several extensions of Bochner's theorem by allowing "small" positive Ricci…

Differential Geometry · Mathematics 2022-08-04 Xiaoyang Chen , Fei Han

Recall that the radius of a compact metric space $(X, dist)$ is given by $rad\ X = \min_{x\in X} \max_{y\in X} dist(x,y)$. In this paper we generalize Berger's $\frac{1}{4}$-pinched rigidity theorem and show that a closed, simply connected,…

dg-ga · Mathematics 2008-02-03 Frederick Wilhelm

Let $M$ be an $n(\geq 4)$-dimensional compact submanifold in the simply connected space form $F^{n+p}(c)$ with constant curvature $c\geq 0$, where $H$ is the mean curvature of $M$. We verify that if the scalar curvature of $M$ satisfies…

Differential Geometry · Mathematics 2019-03-04 Juanru Gu , Hongwei Xu

In this article we present a generalization of a Leibniz's geometrical theorem and an application of it.

General Mathematics · Mathematics 2007-10-02 Mihaly Bencze , Florin Popovici , Florentin Smarandache

The main object of the present paper is to study the geometric properties of a generalized Roter type semi-Riemannian manifold, which arose in the way of generalization to find the form of the Riemann-Christoffel curvature tensor $R$. Again…

Differential Geometry · Mathematics 2014-11-05 Absos Ali Shaikh , Haradhan Kundu

We prove the equivalence between the several notions of generalized Ricci curvature found in the literature. As an application, we characterize when the total generalized Ricci tensor is symmetric.

Differential Geometry · Mathematics 2025-05-14 Gil R. Cavalcanti , Jaime Pedregal , Roberto Rubio

We develop the theory of weighted Ricci curvature in a weighted Lorentz-Finsler framework and extend the classical singularity theorems of general relativity. In order to reach this result, we generalize the Jacobi, Riccati and Raychaudhuri…

Differential Geometry · Mathematics 2021-07-28 Yufeng Lu , Ettore Minguzzi , Shin-ichi Ohta

In this paper we prove that any Riemannian surface, with no restriction of curvature at all, can be decomposed into blocks belonging just to some of these types: generalized Y-pieces, generalized funnels and halfplanes.

Differential Geometry · Mathematics 2008-06-03 Ana Portilla , Jose M. Rodriguez , Eva Touris

We derive general structure and rigidity theorems for submetries $f: M \to X$, where $M$ is a Riemannian manifold with sectional curvature $\sec M \ge 1$. When applied to a non-trivial Riemannian submersion, it follows that $diam X \leq…

Differential Geometry · Mathematics 2014-04-16 Xiaoyang Chen , Karsten Grove

In this paper we present some extensions of the celebrated finite point conformal compactification theorem of Huber \cite{Hu57} for complete open surfaces to general dimensions based on the n-Laplace equations in conformal geometry. We are…

Differential Geometry · Mathematics 2020-12-04 Shiguang Ma , Jie Qing

In this note we relate the geometric notion of fill radius with the fundamental group of the manifold. We prove: ''Suppose that a closed Riemannian manifold M satisfies the property that its universal cover has bounded fill radius. Then the…

Differential Geometry · Mathematics 2009-07-27 Mohan Ramachandran , Jon Wolfson

We consider a generalized Ricci flow with a given (not necessarily closed) three-form and establish the higher derivatives estimates for compact manifolds. As an application, we prove the compactness theorem for this generalized Ricci flow.…

Differential Geometry · Mathematics 2013-01-18 Yi Li

Motivated by Guo-Luo's generalized circle packings on surfaces with boundary \cite{GL2}, we introduce the generalized sphere packings on 3-dimensional manifolds with boundary. Then we investigate the rigidity of the generalized sphere…

Differential Geometry · Mathematics 2023-09-06 Xu Xu , Chao Zheng