English
Related papers

Related papers: Gently Killing S--spaces

200 papers

The aim of this paper is to continue the study of sg-compact spaces. The class of sg-compact spaces is a proper subclass of the class of hereditarily compact spaces. In our paper we shall consider sg-compactness in product spaces. Our main…

General Topology · Mathematics 2007-05-23 Julian Dontchev , Maximilian Ganster

The main purpose of the paper is to find some expansion properties of locally finite metric spaces which do not embed coarsely into a Hilbert space. The obtained result is used to show that infinite locally finite graphs excluding a minor…

Metric Geometry · Mathematics 2009-05-03 M. I. Ostrovskii

It is known that a Killing field on a compact pseudo-K\"ahler manifold is necessarily (real) holomorphic, as long as the manifold satisfies some relatively mild additional conditions. We provide two further proofs of this fact and discuss…

Differential Geometry · Mathematics 2025-08-25 Andrzej Derdzinski

We introduce a ZFC method that enables us to build spaces (in fact special dense subspaces of certain Cantor cubes) in which we have "full control" over all dense subsets. Using this method we are able to construct, in ZFC, for each…

General Topology · Mathematics 2007-05-23 Istvan Juhasz , Lajos Soukup , Zoltan Szentmiklossy

In this work we study the entropies of subsystems of shifts of finite type (SFTs) and sofic shifts on countable amenable groups. We prove that for any countable amenable group $G$, if $X$ is a $G$-SFT with positive topological entropy $h(X)…

Dynamical Systems · Mathematics 2023-02-21 Robert Bland , Kevin McGoff , Ronnie Pavlov

In this paper we study expansions of infinite dimensional Hilbert spaces with a unitary representation of a discrete countable group. When the group is finite, we prove the theory of the corresponding expansion, regardless if it is…

Logic · Mathematics 2025-08-20 Alexander Berenstein , Juan Manuel Pérez

We prove that each metrizable space (of cardinality less or equal to continuum) has a (first countable) uniform Eberlein compactification and each scattered metrizable space has a scattered hereditarily paracompact compactification. Each…

General Topology · Mathematics 2012-12-19 Taras Banakh , Arkady Leiderman

We study universal properties of locally compact G-spaces for countable infinite groups G. In particular we consider open invariant subsets of the \beta-compactification of G (which is a G-space in a natural way), and their minimal closed…

Group Theory · Mathematics 2014-12-09 Hiroki Matui , Mikael Rordam

It is shown that CH implies the existence of a compact Hausdorff space that is countable dense homogeneous, crowded and does not contain topological copies of the Cantor set. This contrasts with a previous result by the author which says…

General Topology · Mathematics 2020-01-20 Rodrigo Hernández-Gutiérrez

All spaces are assumed to be Tychonoff. Given a realcompact space $X$, we denote by $\mathsf{Exp}(X)$ the smallest infinite cardinal $\kappa$ such that $X$ is homeomorphic to a closed subspace of $\mathbb{R}^\kappa$. Our main result shows…

General Topology · Mathematics 2024-11-20 Claudio Agostini , Andrea Medini , Lyubomyr Zdomskyy

In the absence of the Axiom of Choice, necessary and sufficient conditions for a locally compact Hausdorff space to have all non-empty second-countable compact Hausdorff spaces as remainders are given in $\mathbf{ZF}$. Among other…

General Topology · Mathematics 2020-09-22 Kyriakos Keremedis , Eleftherios Tachtsis , Eliza Wajch

In a previous article by the author and P. Wesolek, it was shown that a compactly generated locally compact group $G$ admits a finite normal series $(G_i)$ in which the factors are compact, discrete or irreducible in the sense that no…

Group Theory · Mathematics 2021-06-30 Colin D. Reid

For every uncountable cardinal $\kappa$ there are $2^\kappa$ nonisomorphic simple AF algebras of density character $\kappa$ and $2^\kappa$ nonisomorphic hyperfinite II$_1$ factors of density character $\kappa$. These estimates are maximal…

Operator Algebras · Mathematics 2013-01-28 Ilijas Farah , Takeshi Katsura

We discuss two problems concerning the class Eberlein compacta, i.e., weakly compact subspaces of Banach spaces. The first one deals with preservation of some classes of scattered Eberlein compacta under continuous images. The second one…

General Topology · Mathematics 2021-03-05 Witold Marciszewski

For a separable locally compact but not compact metrizable space $X$, let $\alpha X = X \cup \{x_\infty\}$ be the one-point compactification with the point at infinity $x_\infty$. We denote by $EM(X)$ the space consisting of admissible…

General Topology · Mathematics 2022-02-18 Katsuhisa Koshino

We give necessary conditions for the existence of a compact manifold locally modelled on a given homogeneous space, which generalize some earlier results, in terms of relative Lie algebra cohomology. Applications include both reductive and…

Differential Geometry · Mathematics 2017-05-09 Yosuke Morita

A S(n)-space is S(n)-functionally compact (S(n)FC) if every continuous function onto a S(n)-space is closed. S(n)-closed, S(n)-{\theta}-closed, minimal S(n) and S(n)FC spaces are characterized in terms of {\theta}(n)-complete accumulation…

General Topology · Mathematics 2011-12-23 Alexander V. Osipov

Motivated by the main results of the articles by Hattori and Bouziad, we seek to answer the following questions about Hattori spaces. Let A be a subset of the real line, then: Given a compact set $K$ in the Euclidean topology, under what…

General Topology · Mathematics 2023-09-21 Elmer Enrique Tovar-Acosta

We prove Los conjecture = Morley theorem in ZF, with the same characterization (of first order countable theories categorical in aleph_alpha for some (equivalently for every) ordinal alpha>0. Another central result here is, in this context:…

Logic · Mathematics 2008-07-08 Saharon Shelah

In this paper we study the properties of P-generated spaces (by analogy with compactly generated). We prove that a regular Lindel\"of generated space with uncountable dispersion character is resolvable. It is proved that Hausdorff…

General Topology · Mathematics 2017-12-05 Maria A. Filatova , Alexander V. Osipov
‹ Prev 1 4 5 6 7 8 10 Next ›