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arXiv · 2508.16506

Separating Maximality Principles

Takehiko Gappo·Andreas Lietz
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Abstract

We investigate fragments of generic absoluteness principles known as Maximality Principles. We determine the consistency strength of $Σ_n$-$\mathsf{MP}(\mathbb R)$ and $Π_n$-$\mathsf{MP}(\mathbb R)$, the boldface Maximality Principle restricted respectively to $Σ_n$- and $Π_n$-formulas. Further, we show that no implication between $Σ_n$-$\mathsf{MP}(\mathbb R)$ and $Π_n$-$\mathsf{MP}(\mathbb R)$ is provable in $\mathsf{ZFC}$. We also establish the consistency, relative to a Woodin cardinal, of the Maximality Principle for $ω_1$-preserving posets with countable ordinal parameters and prove its consistency strength is bounded below by a Ramsey cardinal. Finally, we resolve questions of Ikegami-Trang and Goodman by separating the Maximality Principle for stationary set preserving posets restricted to $Σ_2$-formulas from $\mathsf{MM}^{++}$ in the presence of large cardinals.

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Takehiko Gappo, Andreas Lietz. 2025-08-22. Separating Maximality Principles. https://arxiv.org/abs/2508.16506

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