On the number of cofinalities of cuts in ultraproducts of linear orders

2025/01/17 by Golshani, Mohammad
#FOS: Mathematics #Logic (math.LO)

paper · doi:10.48550/arxiv.2501.10294

Abstract

Suppose κ is a regular cardinal and a=⟨ μ_i: i<κ⟩ is a non-decreasing sequence of regular cardinals. We study the set of possible cofinalities of cuts Pcut( a)=\(λ₁, λ₂): for some ultrafilter D on κ, (λ₁, λ₂) is the cofinality of a cut of ∏_i<κ μ_i / D \.

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• On cuts in ultraproducts of linear orders II
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