On regular separable countably compact $\mathbb{R}$-rigid spaces

Serhii Bardyla; Lyubomyr Zdomskyy

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arXiv · 2007.12171

On regular separable countably compact $\mathbb{R}$-rigid spaces

Serhii Bardyla·Lyubomyr Zdomskyy

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Abstract

A topological space $X$ is said to be {\em $Y$-rigid} if any continuous map $f:X\rightarrow Y$ is constant. In this paper we construct a number of examples of regular countably compact $\mathbb R$-rigid spaces with additional properties like separability and first countability. This way we answer several questions of Tzannes, Banakh, Ravsky, as well as get a consistent example of $\mathbb R$-rigid Nyikos space. Also, we show that it is consistent with ZFC that for every cardinal $\kappa<\mathfrak c$ there exists a regular separable countably compact space $X$ which is $Y$-rigid with respect to any $T_1$ space $Y$ of pseudocharacter $\leq\kappa$.

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Serhii Bardyla, Lyubomyr Zdomskyy. 2020-07-23. On regular separable countably compact $\mathbb{R}$-rigid spaces. https://arxiv.org/abs/2007.12171

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