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arXiv · 2109.08130

The Diversity of Minimal Cofinal Extensions

James H. Schmerl
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Abstract

Fix a countable nonstandard model $\mathcal M$ of Peano Arithmetic. Even with some rather severe restrictions placed on the types of minimal cofinal extensions $\mathcal N \succ \mathcal M$ that are allowed, we still find that there are $2^{\aleph_0}$ possible theories of $(\mathcal N,M)$ for such $\mathcal N$'s.

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James H. Schmerl. 2021-09-16. The Diversity of Minimal Cofinal Extensions. https://arxiv.org/abs/2109.08130

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