The additivity of porosity ideals

1993/09/09 by Jörg Brendle, Brendle, Jörg
Mathematics · #Advanced Topology and Set Theory #Commutative Algebra and Its Applications #FOS: Mathematics #Logic (math.LO) #Rings, Modules, and Algebras

paper · pdf · doi:10.48550/arxiv.math/9309206

openalex publication_date 1993/09/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We show that several sigma-ideals related to porous sets have additivity omega₁ and cofinality 2^omega. This answers a question addressed by Miroslav Repick'y.

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