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arXiv · 2111.05038

Constructions of Lindelöf scattered P-spaces

Abstract

We construct locally Lindelöf scattered P-spaces (LLSP spaces, in short) with prescribed widths and heights under different set-theoretic assumptions. We prove that there is an LLSP space of width $ω_1$ and height $ω_2$ and that it is relatively consistent with ZFC that there is an LLSP space of width $ω_1$ and height $ω_3$. Also, we prove a stepping up theorem that, for every cardinal $λ\geq ω_2$, permits us to construct from an LLSP space of width $ω_1$ and height $λ$ satisfying certain additional properties an LLSP space of width $ω_1$ and height $α$ for every ordinal $α< λ^+$. Then, we obtain as consequences of the above results the following theorems: (1) For every ordinal $α< ω_3$ there is an LLSP space of width $ω_1$ and height $α$. (2) It is relatively consistent with ZFC that there is an LLSP space of width $ω_1$ and height $α$ for every ordinal $α< ω_4$.

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BibTeXRIS

Juan Carlos Martínez, Lajos Soukup. 2021-11-09. Constructions of Lindelöf scattered P-spaces. https://arxiv.org/abs/2111.05038

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