English

On first countable, cellular-compact spaces

General Topology 2019-12-19 v3

Abstract

As it was introduced by Tkachuk and Wilson, a topological space XX is cellular-compact if given any cellular, i.e. disjoint, family U\mathcal U of non-empty open subsets of XX there is a compact subspace KXK\subset X such that KUK\cap U\ne \emptyset for each UUU\in \mathcal U. Answering several questions raised by Tkachuk and Wilson we show that (1) any first countable cellular-compact T2T_2 space is T3T_3, and so its cardinality is at most c=2ω\mathfrak{c} = 2^{\omega}; (2) cov(M)>ω1cov(\mathcal M)>{\omega}_1 implies that every first countable and separable cellular-compact T2T_2 space is compact; (3 if there is no SS-space then any cellular-compact T3T_3 space of countable spread is compact; (4) MAω1MA_{{\omega}_1} implies that every point of a compact T2T_2 space of countable spread has a disjoint local π\pi-base.

Keywords

Cite

@article{arxiv.1910.14483,
  title  = {On first countable, cellular-compact spaces},
  author = {István Juhász and Lajos Soukup and Zoltán Szentmiklóssy},
  journal= {arXiv preprint arXiv:1910.14483},
  year   = {2019}
}

Comments

new, revised version, 6 pages

R2 v1 2026-06-23T12:00:53.392Z