Cardinal preserving ideals

1996/05/15 by Moti Gitik, Saharon Shelah, Gitik, Moti +1
Computer Science · Mathematics · #Advanced Algebra and Logic #Advanced Topology and Set Theory #FOS: Mathematics #Logic (math.LO) #Rings, Modules, and Algebras

paper · pdf · doi:10.48550/arxiv.math/9605234

openalex publication_date 1996/05/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We give some general criteria, when kappa-complete forcing preserves largeness properties -- like kappa-presaturation of normal ideals on lambda (even when they concentrate on small cofinalities). Then we quite accurately obtain the consistency strength ``NS_lambda is aleph₁-preserving'', for lambda > aleph₂ .

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