P. Szeptycki

activity

19952026

most citedOn some classes of Lindelöf Sigma-spaces

16 citations · 34 across the 18 of their papers we have counts for

collaborators

Showing 2019 · math.GNShow all

3 papers · 2 filters

math.GN2019

Selectivity properties of spaces

William Chen-Mertens, Paul J. Szeptycki

This paper addresses several questions of Feng, Gruenhage, and Shen which arose from Michael's theory of continuous selections from countable spaces. We construct an example of a s…

math.GN2019

The effect of forcing axioms on the tightness of the $G_{δ}$ modification

William Chen-Mertens, Paul J. Szeptycki

We show that $PFA$ implies that the tightness $t (X_{δ})$ of the $G_{δ}$ -modification of a Fréchet $α_{1}$ -space $X$ is at most $ω_{1}$ , while $□ (κ)$ implies that there is a Fré…

math.GN2019

A 0-dimensional, Lindelöf space that is not strongly D

Daniel T. Soukup, Paul J. Szeptycki

A topological space $X$ is strongly $D$ if for any neighbourhood assignment ${U_{x} : x \in X}$ , there is a $D \subseteq X$ such that ${U_{x} : x \in D}$ covers $X$ and $D$ is locally fin…

Selectivity properties of spaces

The effect of forcing axioms on the tightness of the Gδ​ modification

A 0-dimensional, Lindelöf space that is not strongly D

The effect of forcing axioms on the tightness of the $G_{δ}$ modification