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Related papers: Local convexity in CAT(\kappa)-spaces

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In this paper we study convex subcomplexes of spherical buildings. We pay special attention to fixed point sets of type-preserving isometries of spherical buildings. This sets are also convex subcomplexes of the natural polyhedral structure…

Metric Geometry · Mathematics 2014-08-14 Carlos Ramos-Cuevas

The present paper is concerned with some representatons of linear mappings of continuous functions into locally convex vector spaces, namely: If X is a complete Hausdorff locally convex vector space, then a general form of weakly compact…

Functional Analysis · Mathematics 2012-12-07 Miloslav Duchon

In this paper, we study an interplay between local and global properties of spaces of minimal usco maps equipped with the topology of uniform convergence on compact sets. In particular, for each locally compact space $X$ and metric space…

General Topology · Mathematics 2024-08-15 Serhii Bardyla , Branislav Novotný , Jaroslav Šupina

We prove that the locally convex space $C_{p}(X)$ of continuous real-valued functions on a Tychonoff space $X$ equipped with the topology of pointwise convergence is distinguished if and only if $X$ is a $\Delta$-space in the sense of \cite…

General Topology · Mathematics 2020-12-01 Jerzy Kakol , Arkady Leiderman

We study convex subsets of buildings, discuss some structural features and derive several characterizations of buildings.

Metric Geometry · Mathematics 2007-05-23 Andreas Balser , Alexander Lytchak

In this paper, we prove a local rigidity of convex hypersurfaces in the spaces of constant curvature of dimension $n\ge4$. Namely, we show that two convex isometric hypersurfaces are congruent locally around their corresponding under the…

Differential Geometry · Mathematics 2025-06-24 Alexander A. Borisenko

The classical theory of regularity of embeddings of compact convex sets was developed in the 1970s, exclusively in the real case, and even there it does not appear to have been stated in its simplest form. We begin by revisiting this…

Operator Algebras · Mathematics 2026-02-04 David P. Blecher

We show that the typical nonexpansive mapping on a small enough subset of a CAT($\kappa$)-space is a contraction in the sense of Rakotch. By typical we mean that the set of nonexpansive mapppings without this property is a $\sigma$-porous…

Functional Analysis · Mathematics 2021-08-06 Christian Bargetz , Michael Dymond , Emir Medjic , Simeon Reich

For locally compact groups, we define an analogue to Yu's property A that he defined for discrete metric spaces. We show that our property A for locally compact groups agrees with Roe's notion of property A for proper metric spaces, defined…

Operator Algebras · Mathematics 2013-10-22 Steven Deprez , Kang Li

In this paper, we present the Brouwer-Schauder-Tychonoff fixed point theorem on locally convex spaces as the following extension and improvement: Suppose that S is a compact star-shaped subset with respect to p in S with its convexity index…

Functional Analysis · Mathematics 2026-02-11 Lixin Cheng , Chulei Liu , Wen Zhang

We present an alternative proof of the following fact: the hyperspace of compact closed subsets of constant width in $\mathbb R^n$ is a contractible Hilbert cube manifold. The proof also works for certain subspaces of compact convex sets of…

Metric Geometry · Mathematics 2007-05-23 L. E. Bazylevych , M. M. Zarichnyi

Divisible convex sets have long been important in the study of Hilbert geometries. When a divisible convex set is an ellipsoid, the Hilbert geometry it induces is the hyperbolic space. In general, strictly convex divisible domains exhibit…

Metric Geometry · Mathematics 2024-10-29 Amelia Pompilio

We introduce the property of countable separation for a locally convex Hausdorff space $X$ and relate it to the existence of a metrizable coarser topology. Building on this, we demonstrate how the separability of $X$ is equivalent to the…

Functional Analysis · Mathematics 2025-10-10 Thomas Ruf

We prove the local Lipschitz continuity of sub-elliptic harmonic maps between certain singular spaces, more specifically from the $n$-dimensional Heisenberg group into $CAT(0)$ spaces. Our main theorem establishes that these maps have the…

Differential Geometry · Mathematics 2024-05-15 Renan Assimos , Yaoting Gui , Jürgen Jost

In this paper we introduce Hausdorff locally convex algebra topologies on subalgebras of the whole algebra of nonlinear generalized functions. These topologies are strong duals of Fr\'echet-Schwartz space topologies and even strong duals of…

Functional Analysis · Mathematics 2014-03-21 J. Aragona , J. F. Colombeau , S. O. Juriaans

We prove that each non-separable completely metrizable convex subset of a Frechet space is homeomorphic to a Hilbert space. This resolves an old (more than 30 years) problem of infinite-dimensional topology. Combined with the topological…

Functional Analysis · Mathematics 2011-10-11 Taras Banakh , Robert Cauty

For a Euclidean building $X$ of type $A_{2}$, we classify the 0-dimensional subbuildings $A$ of $\partial_{T}X$ that occur as the asymptotic boundary of closed convex subsets. In particular, we show that triviality of the holonomy of a…

Metric Geometry · Mathematics 2007-05-23 Andreas Balser

We study two properties for subsets of a metric space. One of them is generalization of chainability, finite chainability, and Menger convexity for metric spaces; while the other is a generalization of compactness. We explore the basic…

Geometric Topology · Mathematics 2023-01-19 Ajit Kumar Gupta , Saikat Mukherjee

We show that an embedding of a fixed 0-dimensional compact space $K$ into the \v{C}ech--Stone remainder $\omega^*$ as a nowhere dense P-set is the unique generic limit, a special object in the category consisting of all continuous maps from…

General Topology · Mathematics 2024-07-09 Wiesław Kubiś , Andrzej Kucharski , Sławomir Turek

Motivated by recent breathtaking progress in the synthetic study of Lorentzian geometry, we investigate the local concavity of time separation functions on Finsler spacetimes as a Lorentzian counterpart to Busemann's convexity in metric…

Differential Geometry · Mathematics 2026-02-25 Tobias Beran , Darius Erös , Shin-ichi Ohta , Felix Rott