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Are all F_{σδ} ideals Farah ideals?

Determine whether every F_{σδ} ideal on the natural numbers ω (viewed as a subset of the Cantor space {0,1}^ω with the product topology) is a Farah ideal; equivalently, decide whether the class of F_{σδ} ideals coincides with the class of Farah ideals defined by the existence of a sequence of hereditary compact subsets (K_n)⊆P(ω) such that S∈I iff ∀n∃k S\[0,k]∈K_n.

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Background

The paper recalls that an ideal I on ω is Farah if there exists a sequence (K_n) of hereditary compact subsets of P(ω) such that S∈I iff for all n there exists k with S[0,k]∈K_n. It is known that all analytic P-ideals are Farah and every Farah ideal is F_{σδ}.

The authors explicitly note that the converse direction is not settled: whether every F_{σδ} ideal is Farah. This is a well-known open problem in the structure theory of ideals on ω, relevant to understanding how descriptive-set-theoretic complexity aligns with structural representations of ideals.

References

It is known that all analytic P-ideals are Farah and that all Farah ideals are $F_{\sigma\delta}$. On the other hand, it is still unknown whether the converse holds, namely, all $F_{\sigma\delta}$ ideals are Farah ideals.

Topological complexity of ideal limit points (2407.12160 - Balcerzak et al., 16 Jul 2024) in Section 1 (Introduction), paragraph defining Farah ideals, before Theorem 1.2 (Theorem \ref{thm:xi})