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Related papers: Inradius collapsed manifolds

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If two compact quantum metric spaces are close in the metric sense, then how similar are they, as noncommutative spaces? In the classical realm of Riemannian geometry, informally, if two manifolds are close in the Gromov-Hausdorff distance,…

Operator Algebras · Mathematics 2025-10-16 Carla Farsi , Frederic Latremoliere

For a compact manifold with boundary $X$ we introduce the $n$-fold scattering stretched product $X^n_{\text{sc}}$ which is a compact manifold with corners for each $n,$ coinciding with the previously known cases for $n=2,3.$ It is…

Differential Geometry · Mathematics 2008-08-15 Richard Melrose , Michael Singer

Let $\{X_i\}$ be a sequence of compact $n$-dimensional Alexandrov spaces (e.g. Riemannian manifolds) with curvature uniformly bounded below which converges in the Gromov-Hausdorff sense to a compact Alexandrov space $X$. In an earlier paper…

Differential Geometry · Mathematics 2022-08-16 Semyon Alesker , Mikhail Katz , Roman Prosanov

In this paper we survey a number of recent results concerning the existence and moduli spaces of solutions of various geometric problems on noncompact manifolds. The three problems which we discuss in detail are: I. Complete properly…

dg-ga · Mathematics 2008-02-03 Rafe Mazzeo , Daniel Pollack

In the present paper, we consider the family of all compact Alexandrov spaces with curvature bound below having a definite upper diameter bound of a fixed dimension. We introduce the notion of essential coverings by contractible metric…

Differential Geometry · Mathematics 2012-05-03 Takao Yamaguchi

Submersions with definite folds are submersions on manifolds with boundary whose restrictions to the boundary are definite fold maps. In this paper, we study the properties from the viewpoint of differential topology of manifolds with…

Geometric Topology · Mathematics 2026-04-30 Koki Iwakura

We gather in this note results and examples about collared or non-collared boundaries of non-metrisable manifolds. Almost everything is well known but a bit scattered in the literature, and some of it is apparently not published at all.

General Topology · Mathematics 2022-08-23 Mathieu Baillif

Using the sine-Gordon model as the prime example an alternative approach to integrable boundary conditions for a theory restricted to a half-line is proposed. The main idea is to explore the consequences of taking into account the…

High Energy Physics - Theory · Physics 2012-06-12 E. Corrigan , C. Zambon

This is a survey of topological properties of open, complete nonpositively curved manifolds which may have infinite volume. Topics include topology of ends, restrictions on the fundamental group, as well as a review of known examples.

Differential Geometry · Mathematics 2014-08-05 Igor Belegradek

We consider the relationship of the geometry of compact Riemannian manifolds with boundary to the first nonzero eigenvalue sigma_1 of the Dirichlet-to-Neumann map (Steklov eigenvalue). For surfaces Sigma with genus gamma and k boundary…

Differential Geometry · Mathematics 2010-12-06 Ailana Fraser , Richard Schoen

We establish topological regularity and stability of N-dimensional RCD(K,N) spaces (up to a small singular set), also called non-collapsed RCD(K,N) in the literature. We also introduce the notion of a boundary of such spaces and study its…

Metric Geometry · Mathematics 2021-03-10 Vitali Kapovitch , Andrea Mondino

Consider a compact Riemannian manifold with boundary. In this short note we prove that under certain positive curvature assumptions on the manifold and its boundary the Steklov eigenvalues of the manifold are controlled by the Laplace…

Differential Geometry · Mathematics 2017-05-26 Mikhail A. Karpukhin

Consider a compact, orientable, three dimensional Riemannian manifold with boundary with nonnegative scalar curvature. Suppose its boundary is the disjoint union of two pieces: the horizon boundary and the outer boundary, where the horizon…

Differential Geometry · Mathematics 2009-09-05 Pengzi Miao

Static manifolds with boundary were recently introduced by Cruz and Vit\'orio in the context of the prescribed scalar curvature problem in a manifold with boundary with prescribed mean curvature. This kind of manifold is also interesting…

Differential Geometry · Mathematics 2025-05-12 Stanislav Demurov , Vladimir Medvedev

We show that if a closed manifold M admits an F-structure (possibly of rank 0) then its minimal entropy vanishes. In particular, this is the case if M admits a non-trivial circle action. As a corollary we obtain that the simplicial volume…

Differential Geometry · Mathematics 2007-05-23 Gabriel Paternain , Jimmy Petean

A generic smooth map of a closed $2k$-manifold into $(3k-1)$-space has a finite number of cusps ($\Sigma^{1,1}$-singularities). We determine the possible numbers of cusps of such maps. A fold map is a map with singular set consisting of…

Geometric Topology · Mathematics 2007-05-23 Tobias Ekholm , Andras Szucs , Tamas Terpai

In the prequel of this paper, Kauffman and Ogasa introduced new topological quantum invariants of compact oriented 3-manifolds with boundary where the boundary is a disjoint union of two identical surfaces. The invariants are constructed…

Geometric Topology · Mathematics 2022-03-25 Heather A. Dye , Louis H. Kauffman , Eiji Ogasa

We obtain upper bounds for the isoperimetric quotients of extrinsic balls of submanifolds in ambient spaces which have a lower bound on their radial sectional curvatures. The submanifolds are themselves only assumed to have lower bounds on…

Differential Geometry · Mathematics 2007-09-04 Steen Markvorsen , Vicente Palmer

We prove integral curvature bounds in terms of the Betti numbers for compact submanifolds of the Euclidean space with low codimension. As an application, we obtain topological obstructions for $\delta$-pinched immersions. Furthermore, we…

Differential Geometry · Mathematics 2017-01-26 Christos-Raent Onti , Theodoros Vlachos

In this work, we study compact Riemannian manifolds with boundary satisfying V-static-type equations. By combining a generalized Reilly formula with Steklov-type boundary value problems, we derive integral inequalities for geometric…

Differential Geometry · Mathematics 2026-02-25 Maria Andrade