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Related papers: Noetherian Quasi-Polish Spaces

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The concept of convex compactness, weaker than the classical notion of compactness, is introduced and discussed. It is shown that a large class of convex subsets of topological vector spaces shares this property and that is can be used in…

Functional Analysis · Mathematics 2010-06-02 Gordan Zitkovic

It is a well-known result in pointfree topology that every locally compact frame is spatial. Whether this result extends to MT-algebras (McKinsey-Tarski algebras) was an open problem. We resolve it in the negative by constructing a locally…

General Topology · Mathematics 2025-08-05 G. Bezhanishvili , S. D. Melzer , R. Raviprakash , A. L. Suarez

We study the completeness and ultracompleteness numbers of a convergence space. In the case of a completely regular topological space, the completeness number is countable if and only if the space is $\v{C}$ech-complete, and the…

General Topology · Mathematics 2020-01-01 Frédéric Mynard

We introduce the notion of compactifiable classes -- these are classes of metrizable compact spaces that can be up to homeomorphic copies ``disjointly combined'' into one metrizable compact space. This is witnessed by so-called compact…

General Topology · Mathematics 2020-02-19 A. Bartoš , J. Bobok , J. van Mill , P. Pyrih , B. Vejnar

Generalizations of the theorems of Eberlein and Grothendieck on the precompactness of subsets of function spaces are considered: if $X$ is a countably compact space and $C_p(X)$ is a space of continuous functions in the pointwise topology…

General Topology · Mathematics 2024-11-06 E. A. Reznichenko

Let $(\mathcal C,\otimes,1)$ be an abelian symmetric monoidal category satisfying certain conditions and let $X$ be a scheme over $(\mathcal C,\otimes,1)$ in the sense of To\"en and Vaqui\'{e}. In this paper we show that when $X$ is…

Algebraic Geometry · Mathematics 2016-01-06 Abhishek Banerjee

Let R be an associative ring with identity. We study an elementary generalization of the classical Zariski topology, applied to the set of isomorphism classes of simple left R-modules (or, more generally, simple objects in a complete…

Rings and Algebras · Mathematics 2007-05-23 Edward S. Letzter

In \cite{Chaber}, Chaber has proved that countably compact spaces with a quasi $G_{\delta }$-diagonal are compact. We prove that initially $\kappa $% -compact spaces with a quasi $G_{\kappa }$-diagonal are compact, for any infinite cardinal…

General Topology · Mathematics 2017-05-02 Çetin Vural

Let $X = [0,1]^{n}$, $n \geq1$. We show that the typical (in the sense of Baire category) compact subset of $X$ is not only a zero dimensional Cantor space but it satisfies the property of being strongly microscopic, which is stronger than…

Classical Analysis and ODEs · Mathematics 2020-07-10 Emma D'Aniello , Martina Maiuriello

It is introduced the concept of a quasi-king space, which is a natural generalisation of a king space. In the realm of suborderable spaces, king spaces are precisely the compact spaces, so are the quasi-king spaces. In contrast, quasi-king…

General Topology · Mathematics 2019-02-05 Valentin Gutev

This note is concerned with quasi-perfect morphisms between Noetherian algebraic spaces. In particular, we study the local behavior of quasi-perfect proper morphisms. We show that quasi-perfectness of a proper morphism can be detected at…

Algebraic Geometry · Mathematics 2026-03-18 Timothy De Deyn , Pat Lank , Kabeer Manali Rahul

A topological space $X$ is called Piotrowski if every quasicontinuous map $f:Z\to X$ from a Baire space $Z$ to $X$ has a continuity point. In this paper we survey known results on Piotrowski spaces and investigate the relation of Piotrowski…

General Topology · Mathematics 2021-11-01 Taras Banakh

Open sets and compact saturated sets enjoy a perfect formal symmetry, at least for classes of spaces such as Stone spaces or spectral spaces. For larger classes of spaces, a perfect symmetry may not be available, although strong signs of it…

Logic · Mathematics 2025-07-25 Marco Abbadini , Achim Jung

In a recent paper O. Pavlov proved the following two interesting resolvability results: (1) If a space $X$ satisfies $\Delta(X) > \ps(X)$ then $X$ is maximally resolvable. (2) If a $T_3$-space $X$ satisfies $\Delta(X) > \pe(X)$ then $X$ is…

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

A subset of a Polish space $X$ is called universally small if it belongs to each ccc $\sigma$-ideal with Borel base on $X$. Under CH in each uncountable Abelian Polish group $G$ we construct a universally small subset $A_0\subset G$ such…

General Topology · Mathematics 2012-12-19 Taras Banakh , Nadya Lyaskovska

Newtonian spaces generalize first-order Sobolev spaces to abstract metric measure spaces. In this paper, we study regularity of Newtonian functions based on quasi-Banach function lattices. Their (weak) quasi-continuity is established,…

Functional Analysis · Mathematics 2016-09-23 Lukáš Malý

We construct the space of valuations on a quasi-Polish space in terms of the characterization of quasi-Polish spaces as spaces of ideals of a countable transitive relation. Our construction is closely related to domain theoretical work on…

Logic in Computer Science · Computer Science 2021-10-14 Matthew de Brecht

This paper concerns the self-similarity of topological spaces, in the sense defined in math.DS/0411344. I show how to recognize self-similar spaces, or more precisely, universal solutions of self-similarity systems. Examples include the…

Dynamical Systems · Mathematics 2007-05-23 Tom Leinster

Let $\mathfrak{P}$ be a topological property. We study the relation between the order structure of the set of all $\mathfrak{P}$-extensions of a completely regular space $X$ with compact remainder (partially ordered by the standard partial…

General Topology · Mathematics 2015-02-17 M. R. Koushesh

It is an interesting, maybe surprising, fact that different dense subspaces of even "nice" topological spaces can have different densities. So, our aim here is to investigate the set of densities of all dense subspaces of a topological…

General Topology · Mathematics 2021-09-23 Istvan Juhasz , Jan van Mill , Lajos Soukup , Zoltan Szentmiklossy
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