New examples in the study of selectively separable spaces
Alan Dow, Hayden Pecoraro
公開日: 2025/9/26
Abstract
The property of being selectively separable is well-studied and generalizations such as H-separable and wH-separable have also generated much interest. Bardyla, Maesano, and Zdomskyy proved from Martin's Axiom that there are countable regular wH-separable spaces that are not H-separable. We prove there is a ZFC example. Their example was also Fr\'echet-Urysohn, and we produce two additional examples from weaker assumptions.