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Related papers: Sphere theorems for RCD and stratified spaces

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In this paper, we characterize round spheres in the Euclidean space under some suitable conditions on the r-mean curvature.

Differential Geometry · Mathematics 2020-12-18 Wagner Oliveira Costa-Filho

We give a simple proof of a recent result by Kleinbock and Merrill concerning intrinsic approximations on sphere, in the simplest case of two-dimensional sphere in $\mathbb{R}^3$.

Number Theory · Mathematics 2014-04-11 Nikolay Moshchevitin

We construct flat metrics in a given conformal class with prescribed singularities of real orders at marked points of a closed real surface. The singularities can be small conical, cylindrical, and large conical with possible translation…

Differential Geometry · Mathematics 2011-01-13 Sergiu Moroianu

We construct a spectral sequence associated to a stratified space, which computes the compactly supported cohomology groups of an open stratum in terms of the compactly supported cohomology groups of closed strata and the reduced cohomology…

Algebraic Topology · Mathematics 2017-06-14 Dan Petersen

Free actions of finite groups on spheres give rise to topological spherical space forms. The existence and classification problems for space forms have a long history in the geometry and topology of manifolds. In this article, we present a…

Geometric Topology · Mathematics 2017-08-29 Ian Hambleton

This article is a survey of recent work of the author, together with Markus Banagl, Eric Leichtnam, Rafe Mazzeo, and Paolo Piazza, on the Hodge theory of stratified spaces. We discuss how to resolve a Thom-Mather stratified space to a…

Differential Geometry · Mathematics 2016-03-15 Pierre Albin

There are several well-known characterizations of the sphere as a regular surface in the Euclidean space. By means of a purely synthetic technique, we get a rigidity result for the sphere without any curvature conditions, nor completeness…

Differential Geometry · Mathematics 2015-05-21 Magdalena Caballero , Rafael M. Rubio

In this paper a generalized topological central point theorem is proved for maps of a simplex to finite-dimensional metric spaces. Similar generalizations of the Tverberg theorem are considered.

Algebraic Topology · Mathematics 2012-02-07 R. N. Karasev

We give theorems that can be used to upper bound the densities of packings of different spherical caps in the unit sphere and of translates of different convex bodies in Euclidean space. These theorems extend the linear programming bounds…

Metric Geometry · Mathematics 2014-09-26 David de Laat , Fernando Mario de Oliveira Filho , Frank Vallentin

We analyze the isothermal property in static fluid spheres within the framework of the modified $f(R, T)$ theory of gravitation. The equation of pressure isotropy of the standard Einstein theory is preserved however, the energy density and…

General Relativity and Quantum Cosmology · Physics 2018-09-26 Sudan Hansraj

The spherical centroid body of a centrally-symmetric convex body in the Euclidean unit sphere is introduced. Two alternative definitions - one geometric, the other probabilistic in nature - are given and shown to lead to the same objects.…

Metric Geometry · Mathematics 2019-02-28 Florian Besau , Thomas Hack , Peter Pivovarov , Franz E. Schuster

Given a sphere of any radius $r$ in an $n$-dimensional Euclidean space, we study the coverings of this sphere with solid spheres of radius one. Our goal is to design a covering of the lowest covering density, which defines the average…

Metric Geometry · Mathematics 2018-05-22 Ilya Dumer

We present exact solutions to the Einstein-Maxwell system of equations in spherically symmetric gravitational fields with a specified form of the electric field intensity. The condition of pressure isotropy yields a difference equation with…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. D. Maharaj , K. Komathiraj

We exhibit a Quillen equivalence between two model categories encoding the homotopy theory of stratified spaces : the model category of filtered simplicial sets, and that of filtered spaces. Additionally, we introduce a new class of…

Algebraic Topology · Mathematics 2021-02-10 Sylvain Douteau

A stratified space is a topological space equipped with a \emph{stratification}, which is a decomposition or partition of the topological space satisfying certain extra conditions. More recently, the notion of poset-stratified space, i.e.,…

General Topology · Mathematics 2025-07-09 Lukas Waas , Jon Woolf , Shoji Yokura

We extend Alberti's Rank-One Theorem to $\mathrm{RCD}(K,N)$ metric measure spaces.

Metric Geometry · Mathematics 2024-10-16 Gioacchino Antonelli , Camillo Brena , Enrico Pasqualetto

In the present study we consider the generalized rotational surfaces in Euclidean spaces. Firstly, we consider generalized spherical curves in Euclidean $(n+1)-$space $\mathbb{E}^{n+1}$. Further, we introduce some kind of generalized…

Differential Geometry · Mathematics 2016-05-03 Bengu Bayram , Kadri Arslan , Betul Bulca

We provide a simple topological derivation of a formula for the Reidemeister and the analityc torsion of spheres.

Geometric Topology · Mathematics 2009-06-16 T. de Melo , M. Spreafico

We prove that any steady solution to the real analytic Euler equations on a Riemannian 3-sphere must possess a periodic orbit bounding an embedded disc. One key ingredient is an extension of Fomenko's work on the topology of integrable…

Dynamical Systems · Mathematics 2007-05-23 John B. Etnyre , Robert W. Ghrist

We prove that a space whose topological complexity equals 1 is homotopy equivalent to some odd-dimensional sphere. We prove a similar result, although not in complete generality, for spaces X whose higher topological complexity TC_n(X) is…

Algebraic Topology · Mathematics 2012-07-20 Mark Grant , Gregory Lupton , John Oprea