On first countable, cellular-compact spaces

Abstract

As it was introduced by Tkachuk and Wilson, a topological space X is cellular-compact if given any cellular, i.e. disjoint, family U of non-empty open subsets of X there is a compact subspace K⊂ X such that K U for each U∈ U. Answering several questions raised by Tkachuk and Wilson we show that (1) any first countable cellular-compact T2 space is T3, and so its cardinality is at most c = 2ω; (2) cov( M)>ω1 implies that every first countable and separable cellular-compact T2 space is compact; (3 if there is no S-space then any cellular-compact T3 space of countable spread is compact; (4) MAω1 implies that every point of a compact T2 space of countable spread has a disjoint local π-base.

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