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arXiv · 2301.12748

Resolvability and complete accumulation points

Abstract

We prove that: I. For every regular Lindelöf space $X$ if $|X|=Δ(X)$ and $\mathrm{cf}|X|\neω$, then $X$ is maximally resolvable; II. For every regular countably compact space $X$ if $|X|=Δ(X)$ and $\mathrm{cf}|X|=ω$, then $X$ is maximally resolvable. Here $Δ(X)$, the dispersion character of $X$, is the minimum cardinality of a nonempty open subset of $X$. Statements I and II are corollaries of the main result: for every regular space $X$ if $|X|=Δ(X)$ and every set $A\subseteq X$ of cardinality $\mathrm{cf}|X|$ has a complete accumulation point, then $X$ is maximally resolvable. Moreover, regularity here can be weakened to $π$-regularity, and the Lindelöf property can be weakened to the linear Lindelöf property.

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BibTeXRIS

A. E. Lipin. 2023-01-30. Resolvability and complete accumulation points. https://arxiv.org/abs/2301.12748

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