arXiv · 2002.06639
If M is a nonstandard model of Peano Arithmetic, then M is lofty iff M has a simple elementary extension that is recursively saturated. This had previously been known for countable M.
James H. Schmerl. 2020-02-16. Lofty Models of Peano Arithmetic. https://arxiv.org/abs/2002.06639
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