Commit 2026-07-03 08:36 4d076302
View on Github →feat(CategoryTheory/Presentable): sharply smaller regular cardinals (#40937)
In this file, we introduce the predicate Cardinal.SharplyLT. Given two regular
cardinals κ₁ < κ₂, this condition can be described in different ways (a TFAE lemma will appear in a future PR). Here, we define it by saying that the category CardinalDirectedPoset κ₁ is κ₂-accessible, and we show one of the implications for the future TFAE lemma.
(This PR also renames CardinalFilteredPoset as CardinalDirectedPoset.)
Estimated changes
added theorem Cardinal.SharplyLT.existsIsCardinalFilteredSetOfExistsCofinal.hasCardinalLT_transfiniteIterate_φ
added theorem Cardinal.SharplyLT.existsIsCardinalFilteredSetOfExistsCofinal.isCardinalFiltered_iUnion