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In this paper for each cardinal $\kappa$ we construct an infinite $\kappa$-bounded (and hence countably compact) regular space $R_{\kappa}$ such that for any $T_1$ space $Y$ of pseudo-character $\leq\kappa$, each continuous function…

General Topology · Mathematics 2020-01-23 Serhii Bardyla , Alexander V. Osipov

We develop a version of Cichon's diagram for cardinal invariants on the generalized Cantor space 2^kappa or the generalized Baire space kappa^kappa where kappa is an uncountable regular cardinal. For strongly inaccessible kappa, many of the…

Logic · Mathematics 2016-11-28 Joerg Brendle , Andrew Brooke-Taylor , Sy-David Friedman , Diana Montoya

The main result of this paper is that, under PFA, for every {\em regular} space $X$ with $F(X) = \omega$ we have $|X| \le w(X)^\omega$; in particular, $w(X) \le \mathfrak{c}$ implies $|X| \le \mathfrak{c}$. This complements numerous prior…

General Topology · Mathematics 2022-02-02 Alan Dow , Istvan Juhasz

We study the influence of the existence of large cardinals on the existence of wellorderings of power sets of infinite cardinals $\kappa$ with the property that the collection of all initial segments of the wellordering is definable by a…

Logic · Mathematics 2017-04-04 Philipp Lücke , Philipp Schlicht

Let $X$ be a compact metric space and let $|A|$ denote the cardinality of a set $A$. We prove that if $f\colon X\to X$ is a homeomorphism and $|X|=\infty$ then for all $\delta>0$ there is $A\subset X$ such that $|A|=4$ and for all $k\in Z$…

Dynamical Systems · Mathematics 2014-04-03 Alfonso Artigue

Much recent work in cardinal characteristics has focused on generalizing results about $\omega$ to uncountable cardinals by studying analogues of classical cardinal characteristics on the generalized Baire and Cantor spaces $\kappa^\kappa$…

Logic · Mathematics 2021-09-01 Corey Bacal Switzer

We study the approachability ideal I[\kappa^+] in the context of large cardinals properties of the regular cardinals below a singular \kappa. As a guiding example consider the approachability ideal I[\aleph_{\omega+1}] assuming that…

Logic · Mathematics 2008-04-07 Assaf Sharon , Matteo Viale

Given an uncountable cardinal $\kappa$, we consider the question of whether subsets of the power set of $\kappa$ that are usually constructed with the help of the Axiom of Choice are definable by $\Sigma_1$-formulas that only use the…

Logic · Mathematics 2023-09-20 Philipp Lücke , Sandra Müller

Let $\kappa$ be an infinite cardinal. A topological space $X$ is $\kappa$-bounded if the closure of any subset of cardinality $\le\kappa$ in $X$ is compact. We discuss the problem of embeddability of topological spaces into Hausdorff…

General Topology · Mathematics 2021-11-02 T. Banakh , S. Bardyla , A. Ravsky

One of the numerous characterizations of a Ramsey cardinal kappa involves the existence of certain types of elementary embeddings for transitive sets of size \kappa satisfying a large fragment of ZFC. We introduce new large cardinal axioms…

Logic · Mathematics 2011-04-25 Victoria Gitman

We construct a variety of inner models exhibiting features usually obtained by forcing over universes with large cardinals. For example, if there is a supercompact cardinal, then there is an inner model with a Laver indestructible…

Logic · Mathematics 2011-11-04 Arthur Apter , Victoria Gitman , Joel David Hamkins

It is well-known that every non-isolated point in a compact Hausdorff space is the accumulation point of a discrete subset. Answering a question raised by Z. Szentmiklossy and the first author, we show that this statement fails for…

General Topology · Mathematics 2013-07-09 Istvan Juhasz , Saharon Shelah

We study connections between definability in generalized descriptive set theory and large cardinals, under ZFC. We show that if $\kappa$ is a limit of measurables then there is no wellorder of a subset of $P(\kappa)$ of length…

Logic · Mathematics 2026-03-13 Farmer Schlutzenberg

The {\em Singular Cardinal Hypothesis} (SCH) is one of the most classical combinatorial principles in set theory. It says that if $\kappa$ is singular strong limit, then $2^{\kappa}=\kappa^+$. We prove that given a singular cardinal…

Logic · Mathematics 2022-02-23 Sittinon Jirattikansakul

We summarize the known methods of producing a non-supercompact strongly compact cardinal and describe some new variants. Our Main Theorem shows how to apply these methods to many cardinals simultaneously and exactly control which cardinals…

Logic · Mathematics 2007-05-23 Arthur W. Apter , Joel David Hamkins

We show that there are locally compact spaces that can be condensed onto separable spaces but not onto compact separable spaces. We also show that for every cardinal $\kappa$ there is a locally compact topological group of cardinality…

General Topology · Mathematics 2025-11-19 István Juhász , Jan van Mill , Lajos Soukup

According to a folklore characterization of supercompact spaces, a compact Hausdorff space is supercompact if and only if it has a binary closed $k$-network. This characterization suggests to call a topological space $super$ if it has a…

General Topology · Mathematics 2020-04-09 Taras Banakh , Zdzisław Kosztołowicz , Sławomir Turek

The topological reconstruction problem asks how much information about a topological space can be recovered from its point-complement subspaces. If the whole space can be recovered in this way, it is called reconstructible. Our main result…

General Topology · Mathematics 2015-01-21 Max F. Pitz

We show in detail that every compact countable subset of a metric space is homeomorphic to a countable ordinal number, which extends a result given by Mazurkiewicz and Sierpinski for finite-dimensional Euclidean spaces. In order to achieve…

General Topology · Mathematics 2019-11-12 Borys Álvarez-Samaniego , Andrés Merino

In this article we proved so-called strong reflection principles corresponding to formal theories Th which has omega-models. An posible generalization of the Lob's theorem is considered.Main results is: (1) let $k$ be an inaccessible…

General Mathematics · Mathematics 2019-10-08 Jaykov Foukzon
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