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Strictness of the Σ_n-correct forcing axiom hierarchy for n>2

Determine whether, for n>2 and any n‑nice forcing class Γ, the axiom Σ_{n+1}–CFA_{<κ}(Γ) is strictly stronger than Σ_n–CFA_{<κ}(Γ), i.e., whether Σ_{n+1}–CFA_{<κ}(Γ) does not follow from Σ_n–CFA_{<κ}(Γ).

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Background

The chapter examines partial separations showing that Σn–CFA{<κ}(Γ) need not imply Σ{n+2}–CFA{<κ}(Γ). The remaining open issue is whether consecutive levels are strictly separated for n>2.

References

We are left with the following open questions, where a positive answer to the first would easily yield a positive answer to the second: Is $\Sigma_{n+1}\mhyphen CFA_{<\kappa}(\Gamma)$ a strictly stronger axiom than $\Sigma_n\mhyphen CFA_{<\kappa}(\Gamma)$ when $n>2$?

$Σ_n$-correct Forcing Axioms (2405.09674 - Goodman, 15 May 2024) in Section 3.3 (Do Σ_n-correct Forcing Axioms Form a Strict Hierarchy in n?)