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arXiv · 2107.05947

Higher Dimensional Cardinal Characteristics for Sets of Functions II

Jörg Brendle·Corey Bacal Switzer
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Abstract

We study the values of the higher dimensional cardinal characteristics for sets of functions $f:ω^ω\to ω^ω$ introduced by the second author. We prove that while the bounding numbers for these cardinals can be strictly less than the continuum, the dominating numbers cannot. We compute the bounding numbers for the higher dimensional relations in many well known models of $\neg\mathsf{CH}$ such as the Cohen, random and Sacks models and, as a byproduct show that, with possibly one exception, for the bounding numbers there are no $\mathsf{ZFC}$ relations between them beyond those in the higher dimensional Cichoń diagram. In the case of the dominating numbers we show that in fact they collapse in the sense that modding out by the ideal does not change their values. Moreover, they are closely related to the dominating numbers $\mathfrak{d}^λ_κ$.

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Jörg Brendle, Corey Bacal Switzer. 2022-02-18. Higher Dimensional Cardinal Characteristics for Sets of Functions II. https://arxiv.org/abs/2107.05947

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