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Equivalence of MM^{+ω1} and Σ_2–CMM

Determine whether Martin’s Maximum with ω1 many stationary set names (MM^{+ω1}) is equivalent to the Σ_2-correct stationary-set-preserving forcing axiom Σ_2–CMM.

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Background

The paper presents several equivalent formulations of Σ_n–CFA and compares them to strengthened classical axioms like FA{+}. Whether MM{+ω1} coincides with Σ_2–CMM remains unsettled and would calibrate the exact strength of Σ_2–CMM relative to well-studied enhancements of MM.

References

To conclude this section, consider the following open question: Is $MM{+\omega_1}$ equivalent to $\Sigma_2\mhyphen CMM$?

$Σ_n$-correct Forcing Axioms (2405.09674 - Goodman, 15 May 2024) in Section 3.2 (Equivalent Formulations)