On absolutely divergent series

Sakaé Fuchino; Heike Mildenberger; Saharon Shelah; Peter Vojtáš

ArticleOriginal scientific text

Title

On absolutely divergent series

Authors ¹, ^2,³, ⁴, ⁵

Affiliations

Sakaé Fuchino, Department of Computer Sciences, Kitami Institute of Technology, Koen-cho 165, Kitami, Hokkaido 090 Japan
Mathematisches Institut, Universität Bonn, Beringstr. 1 53115 Bonn, Germany
Mathematical Institute, The Hebrew University of Jerusalem, Givat Ram, 91904 Jerusalem, Israel
Mathematical Institute, The Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
Mathematical Institute, Slovak Academy of Sciences, Jesenná 5, 04154 Košice, Slovak Republic

Abstract

We show that in the

ℵ_{2}

-stage countable support iteration of Mathias forcing over a model of CH the complete Boolean algebra generated by absolutely divergent series under eventual dominance is not isomorphic to the completion of P(ω)/fin. This complements Vojtáš' result that under

c f (g c) = g p

the two algebras are isomorphic [15].

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Title

On absolutely divergent series

Affiliations

Abstract

Bibliography