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arXiv · 2503.10514

Cardinal invariants associated with the combinatorics of the uniformity number of the ideal of meager-additive sets

Miguel A. Cardona
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Abstract

In [CMRM24], it was proved that it is relatively consistent that \emph{bounding number} $\mathfrak{b}$ is smaller than the uniformity of $\mathcal{MA}$, where $\mathcal{MA}$ denotes the ideal of the meager-additive sets of $2^ω$. To establish this result, a specific cardinal invariant, which we refer to as $\mathfrak{b}_b^\mathsf{eq}$, was introduced in close relation to Bartoszyński's and Judah's characterization of the uniformity of $\mathcal{MA}$. This survey aims to explore this cardinal invariant along with its dual, which we call as $\mathfrak{d}_b^\mathsf{eq}$. In particular, we will illustrate its connections with the cardinals represented in Cichoń's diagram. Furthermore, we will present several open problems pertaining to these cardinals.

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Miguel A. Cardona. 2025-03-13. Cardinal invariants associated with the combinatorics of the uniformity number of the ideal of meager-additive sets. https://arxiv.org/abs/2503.10514

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