A ug 2 00 9 LINEAR σ - ADDITIVITY AND SOME APPLICATIONS
نویسنده
چکیده
We show that countable increasing unions preserve a large family of well-studied covering properties, which are not necessarily σ-additive. Using this, together with infinite-combinatorial methods and simple forcing theoretic methods, we explain several phenomena, settle problems of Just, Miller, Scheepers and Szeptycki [15], Gruenhage and Szeptycki [13], Tsaban and Zdomskyy [33], and Tsaban [29, 32], and construct topological groups with very strong combinatorial properties.
منابع مشابه
2 8 Ju n 20 09 LINEAR σ - ADDITIVITY AND SOME APPLICATIONS
We show that a large family of well-studied covering properties, which are not necessarily σ-additive, are preserved by countable increasing unions. Using this and simple forcing theoretic methods, we explain several phenomena, settle some problems, and construct topological groups with very strong combinatorial properties.
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