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Farah’s conjecture on coanalytic ideals

Prove or refute the conjecture that every coanalytic (Π1_1) ideal on ω is a Farah ideal, i.e., there exists a sequence of hereditary compact sets {K_n}⊆P(ω) such that S∈I iff ∀n ∃k (S\k ∈ K_n).

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Background

Farah ideals admit a compact hereditary representation and are known to be Π0_3 (Fσδ). The paper notes: if every Π1_1 ideal were Farah, then for such ideals either L(I)=Π0_1 or L(I)=Σ0_2 would follow, settling the main open question in the coanalytic case.

The authors explicitly cite and rely on the conjecture as a potential route to resolving their dichotomy for L(I).

References

Farah conjectured ([24, p. 199]) that every II] ideal is a Farah ideal.

Borel complexity of sets of ideal limit points (2411.10866 - Filipow et al., 16 Nov 2024) in Section 10.3 (Remark 10.10)