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arXiv · math/0105045

Selection principles and the minimal tower problem

Abstract

We study diagonalizations of covers using various selection principles, where the covers are related to linear quasiorderings (tau-covers). This includes: equivalences and nonequivalences, combinatorial characterizations, critical cardinalities and constructions of special sets of reals. This study leads to a solution of a topological problem which was suggested to the author by Scheepers (and stated in an earlier work) and is related to the Minimal Tower problem. We also introduce a variant of the notion of tau-cover, called tau^*-cover, and settle some problems for this variant which are still open in the case of $τ$-covers. This new variant introduces new (and tighter) topological and combinatorial lower bounds on the Minimal Tower problem.

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BibTeXRIS

Boaz Tsaban. 2007-05-17. Selection principles and the minimal tower problem. https://doi.org/10.1285/i15900932v22n2p53

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