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arXiv · 2404.03315

The complexity of non-stationary ideals

Philipp Lücke
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Abstract

We present an overview of results on the question of whether the non-stationary ideal of an uncountable regular cardinal $κ$ can be defined by a $Π_1$-formula using parameters of hereditary cardinality at most $κ$. These results show that this question is deeply connected to several central topics of current research in set theory.

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Philipp Lücke. 2024-04-17. The complexity of non-stationary ideals. https://arxiv.org/abs/2404.03315

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