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arXiv · 2206.14703

A friendly iteration forcing that the four cardinal characteristics of $\mathcal{E}$ can be pairwise different

Miguel A. Cardona
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Abstract

Let $\mathcal{E}$ be the $\sigma$-ideal generated by the closed measure zero sets of reals. We use an ultrafilter-extendable matrix iteration of ccc posets to force that, for $\mathcal{E}$, their associated cardinal characteristics (i.e.\ additivity, covering, uniformity and cofinality) are pairwise different.

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Miguel A. Cardona. 2022-06-29. A friendly iteration forcing that the four cardinal characteristics of $\mathcal{E}$ can be pairwise different. https://arxiv.org/abs/2206.14703

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