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Relating S_{I,ε} to Gajda–Miller families N_J^* and N_J

Clarify the relationships—containments or equalities—between the layered σ-ideals S_{I,ε} and the families N_J^* and N_J (defined from an ideal J on ω) introduced by Gajda and Miller, for varying choices of partition I of ω into finite nonempty intervals and ε ∈ ℓ^1_+.

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Background

The concluding remarks note prior work of Gajda and Miller that defines intermediate families N_J* and N_J with E ⊆ N_J* ⊆ N_J ⊆ N. Given the placement of S_{I,ε} between E and N in the paper’s inclusion diagram, it is natural to ask how S_{I,ε} compares to N_J* and N_J.

Answering this would situate the layered ideals within the broader landscape of definable smallness notions and could reveal new structural or combinatorial characterizations.

References

We discuss some open questions from this study. With regard to~\autoref{cichonext} and items~\ref{cohen}-\ref{miller}, we do not know the following. What is the relation among the $\sigma$-ideals $S_{I,\varepsilon}$, $N_J\ast$, and $N_J$?

Cardinal characteristics associated with small subsets of reals (2405.11312 - Cardona et al., 18 May 2024) in Section Open Questions