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arXiv · 2207.02444

Singular precalibers for topological products

Alejandro Ríos-Herrejón
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Abstract

In this paper we prove that if $κ$ is a singular cardinal with uncountable cofinality, then every power of a given topological space with precaliber $κ$ has precaliber $κ$ as well. Furthermore, if $\{X_α: α<λ\}$ is a family of topological spaces with precaliber $κ$ and $λ<cf(κ)$, then $κ$ is a precaliber for the topological product $\prod\{X_α: α<λ\}$.

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Alejandro Ríos-Herrejón. 2022-07-21. Singular precalibers for topological products. https://doi.org/10.1016/j.topol.2022.108190

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