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arXiv · 2404.18571

Cascading Variants of Internal Approachability

Hannes Jakob
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Abstract

We construct models in which there are stationarily many structures that exhibit different variants of internal approachability at different levels. This answers a question of Foreman-Todorcevic. We also show that the approachability property at $μ$ is consistent with having a distinction between variants of internal approachability for stationarily many $N\in[H(μ^+)]^μ$, answering a question of Levine.

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Hannes Jakob. 2026-06-30. Cascading Variants of Internal Approachability. https://arxiv.org/abs/2404.18571

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