Selective sequential pseudocompactness

Alejandro Dorantes-Aldama; Dmitri Shakhmatov

doi:10.1016/j.topol.2017.02.016

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arXiv · 1702.02055

Selective sequential pseudocompactness

Alejandro Dorantes-Aldama·Dmitri Shakhmatov

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Abstract

We say that a topological space X is selectively sequentially pseudocompact (SSP for short) if for every sequence (U_n) of non-empty open subsets of X, one can choose a point x_n in U_n for every n in such a way that the sequence (x_n) has a convergent subsequence. We show that the class of SSP spaces is closed under taking arbitrary products and continuous images, contains the class of all dyadic spaces and forms a proper subclass of the class of strongly pseudocompact spaces introduced recently by García-Ferreira and Ortiz-Castillo. We investigate basic properties of this new class and its relations with known compactness properties. We prove that every omega-bounded (=the closure of which countable set is compact) group is SSP, while compact spaces need not be SSP. Finally, we construct SSP group topologies on both the free group and the free Abelian group with continuum-many generators.

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BibTeX RIS

Alejandro Dorantes-Aldama, Dmitri Shakhmatov. 2017-02-07. Selective sequential pseudocompactness. https://doi.org/10.1016/j.topol.2017.02.016

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