Towers and clubs

Pierre Matet

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arXiv · 1908.05336

Towers and clubs

Pierre Matet

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Abstract

We revisit several results concerning club principles and nonsaturation of the nonstationary ideal, attempting to improve them in various ways. So we typically deal with a (non necessarily normal) ideal $J$ extending the nonstationary ideal on a regular uncountable (non necessarily successor) cardinal $\kappa$, our goal being to witness the nonsaturation of $J$ by the existence of towers (of length possibly greater than $\kappa^+$).

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Pierre Matet. 2019-08-14. Towers and clubs. https://arxiv.org/abs/1908.05336

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