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arXiv · 2403.00205

A Wallace semigroup whose every finite power is countably compact

Juan Luis Jaisuño Fuentes-Maguiña·Vinicius de Oliveira Rodrigues·Artur Hideyuki Tomita
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Abstract

We show that, assuming the existence of $\mathfrak{c}$ incomparable selective ultrafilters, there exists a Wallace semigroup whose infinite countable power is the least power which fails to be countably compact. This answers positively Question 9.4 of \cite{Tomita15}.

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Juan Luis Jaisuño Fuentes-Maguiña, Vinicius de Oliveira Rodrigues, Artur Hideyuki Tomita. 2024-03-01. A Wallace semigroup whose every finite power is countably compact. https://arxiv.org/abs/2403.00205

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