A non-trivially non-trivial automorphism at an inaccessible cardinal

Márk Poór; Jing Zhang

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arXiv · 2609.08061

A non-trivially non-trivial automorphism at an inaccessible cardinal

Márk Poór·Jing Zhang

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Abstract

We show that, relative to the existence of an inaccessible cardinal, it is consistent that for an inaccessible cardinal $\kappa$, there is a non-trivial automorphism of $\mathcal{P}(\kappa)/\mathrm{fin}$ whose restriction to $\mathcal{P}(\beta)/\mathrm{fin}$ is induced by a bijection on $\beta$ for every $\beta<\kappa$. This answers questions posed by Larson--McKenney, Shelah--Stepr\=ans, and Veli\v{c}kovi\'{c}.

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BibTeX RIS

Márk Poór, Jing Zhang. 2026-09-07. A non-trivially non-trivial automorphism at an inaccessible cardinal. https://arxiv.org/abs/2609.08061

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