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arXiv · 1708.06587

Selectively sequentially pseudocompact group topologies on torsion and torsion-free Abelian groups

Abstract

A space X is selectively sequentially pseudocompact if for every sequence (U_n) of non-empty open subsets of X, one can choose a point x_n in each U_n in such a way that the sequence (x_n) has a convergent subsequence. Let G be a group from one of the following three classes: (i) V-free groups, where V is an arbitrary variety of Abelian groups; (ii) torsion Abelian groups; (iii) torsion-free Abelian groups. Under the Singular Cardinal Hypothesis SCH, we prove that if G admits a pseudocompact group topology, then it can also be equipped with a selectively sequentially pseudocompact group topology. Since selectively sequentially pseudocompact spaces are strongly pseudocompact in the sense of García-Ferreira and Ortiz-Castillo, this provides a strong positive (albeit partial) answer to a question of García-Ferreira and Tomita.

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BibTeXRIS

Alejandro Dorantes-Aldama, Dmitri Shakhmatov. 2017-08-22. Selectively sequentially pseudocompact group topologies on torsion and torsion-free Abelian groups. https://doi.org/10.1016/j.topol.2017.08.020

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