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We completely describe inhomogeneous properly embedded almost symmetric submanifolds of Euclidean space as certain unions of parallel symmetric submanifolds of the ambient Euclidean space.

Differential Geometry · Mathematics 2026-01-13 Claudio Gorodski , Carlos Olmos

For mappings in metric spaces satisfying one inequality with respect to modulus of families of curves, there is proved a lightness of the uniform limit of these mappings. It is proved that, the uniform limit of these mappings is light…

Metric Geometry · Mathematics 2018-01-31 E. A. Sevost'yanov , S. A. Skvortsov

This paper studies a specific metric on plane curves that has the property of being isometric to classical manifold (sphere, complex projective, Stiefel, Grassmann) modulo change of parametrization, each of these classical manifolds being…

Differential Geometry · Mathematics 2008-05-05 Peter W. Michor , David Mumford , Jayant Shah , Laurent Younes

Let k be at most 0, and let X be a locally-finite CAT(k) polyhedral 2-complex X, each face with constant curvature k. Let E be a closed, rectifiably-connected subset of X with trivial first singular homology. We show that E, under the…

Metric Geometry · Mathematics 2021-08-25 Russell Ricks

We discuss some basic properties of polar convergence in metric spaces. Polar convergence is closely connected with the notion of Delta-convergence of T.C. Lim known for several years. Possible existence of a topology which induces polar…

Functional Analysis · Mathematics 2016-01-14 Giuseppe Devillanova , Sergio Solimini , Cyril Tintarev

Consider the semialgebraic structure over the real field. More generally, let an ominimal structure be over a real closed field. We show that a definable metric space X with a definable metric d is embedded into a Euclidean space so that…

Algebraic Geometry · Mathematics 2017-08-31 Masahiro Shiota

We introduce "weakly chained spaces", which need not be locally connected or path connected, but for which one has a reasonable notion of generalized fundamental group and associated generalized universal cover. We show that in the compact…

Algebraic Topology · Mathematics 2021-03-16 Conrad Plaut

We consider (compact or noncompact) Lorentzian manifolds whose holonomy group has compact closure. Among other results, we obtain that this property is equivalent to admitting a parallel timelike vector field. We also derive some properties…

Differential Geometry · Mathematics 2016-03-24 Manuel Gutiérrez , Olaf Müller

This paper discusses a new family of bounds for use in similarity search, related to those used in metric indexing, but based on Ptolemy's inequality, rather than the metric axioms. Ptolemy's inequality holds for the well-known Euclidean…

Data Structures and Algorithms · Computer Science 2015-07-08 Magnus Lie Hetland

There is a well developed theory of weakly symmetric Riemannian manifolds. Here it is shown that several results in the Riemannian case are also valid for weakly symmetric pseudo-Riemannian manifolds, but some require additional hypotheses.…

Differential Geometry · Mathematics 2011-07-26 Zhiqi Chen , Joseph A. Wolf

Quadric complexes are square complexes satisfying a certain combinatorial nonpositive curvature condition. These complexes generalize 2-dimensional CAT(0) cube complexes and are a square analog of systolic complexes. We introduce and study…

Group Theory · Mathematics 2019-11-27 Nima Hoda

We prove a Sobolev inequality which holds on submanifolds in Euclidean space of arbitrary dimension and codimension. This inequality is sharp if the codimension is at most 2. As a special case, we obtain a sharp isoperimetric inequality for…

Differential Geometry · Mathematics 2020-10-07 S. Brendle

This paper studies the magnitude homology groups of geodesic metric spaces. We start with a description of the second magnitude homology of a general metric space in terms of the zeroth homology groups of certain simplicial complexes. Then,…

Algebraic Topology · Mathematics 2025-04-30 Kiyonori Gomi

In this paper we examine two basic topological properties of partial metric spaces, namely compactness and completeness. Our main result claims that in these spaces compactness is equivalent to sequential compactness. We also show that…

General Topology · Mathematics 2022-02-01 Dariusz Bugajewski , Piotr Maćkowiak , Ruidong Wang

A metric space is indivisible if for any partition of it into finitely many pieces one piece contains an isometric copy of the whole space. Continuing our investigation of indivisible metric spaces, we show that a countable ultrametric…

Metric Geometry · Mathematics 2007-05-23 Christian Delhommé , Claude Laflamme , Maurice Pouzet , Norbert Sauer

We study compact almost complex manifolds admitting a Hermitian metric satisfying an integral condition involving $\overline \partial$-harmonic $(0,1)$-forms. We prove that this integral condition is automatically satisfied, if the…

Differential Geometry · Mathematics 2023-02-08 Anna Fino , Nicoletta Tardini , Adriano Tomassini

An embeddability criterion for zero-dimensional metrizable topological spaces in zero-dimensional metrizable topological groups is given. A space which can be embedded as a closed subspace in a zero-dimensional metrizable group but is not…

General Topology · Mathematics 2007-05-23 Ol'ga V. Sipacheva

The class of the hypercomplex pseudo-Hermitian manifolds is considered. The flatness of the considered manifolds with the 3 parallel complex structures is proved. Conformal transformations of the metrics are introduced. The conformal…

Differential Geometry · Mathematics 2012-03-27 Kostadin Gribachev , Mancho Manev , Stancho Dimiev

For every simplicial complex X, we construct a locally CAT(0) cubical complex T_X, a cellular isometric involution i on T_X and a map t_X from T_X to X with the following properties: t_Xi = t_X; t_X is a homology isomorphism; the induced…

Group Theory · Mathematics 2014-02-26 Ian J. Leary

Petyt-Spriano-Zalloum recently developed the notion of a \textit{curtain model}, which is a hyperbolic space associated to any CAT(0) space. It plays a similar role for CAT(0) spaces that curve graphs do for mapping class groups of…

Metric Geometry · Mathematics 2023-12-29 Elliott Vest