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Separation for non–self-preserving classes: MP+RRP without CBFA

Determine whether there exists, for a forcing class Γ that is never self-preserving, a model (for suitable κ and λ) in which the Σ_n maximality principle Σ_n–MP_Γ(H_κ) and the Σ_n residual reflection principle Σ_n–RRP(κ,λ,Γ) both hold while the bounded Σ_n-correct forcing axiom Σ_n–CBFA_{<κ}^{<λ}(Γ) fails.

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Background

The paper’s factorization result covers provably self-preserving classes. To see whether factorization genuinely fails beyond that field, one would need a separation showing MP+RRP can hold while CBFA fails for a class Γ that is never self-preserving.

References

Further open questions arise from the fact that, although the proof of Theorem \ref{thm:cbfafactor} does not appear to generalize beyond the provably self-preserving classes, it is unclear how to establish the separations that would definitively show that the theorem does not generalize: Is it consistent for suitable $\kappa$ that $\Sigma_n\mhyphen MP_\Gamma(H_\kappa)$ and $\Sigma_n\mhyphen RRP(\kappa, \lambda, \Gamma)$ hold but $\Sigma_n\mhyphen CBFA_{<\kappa}{<\lambda}(\Gamma)$ fails?

$Σ_n$-correct Forcing Axioms (2405.09674 - Goodman, 15 May 2024) in Section 7 (Residual Reflection Principles), end of section