Cotorsion theories cogenerated by N1-free abelian groups

Saharon Shelah, Lutz Strüngmann

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

Given an N1-free abelian group G we characterize the class CG of all torsion abelian groups T satisfying Ext (G, T) = 0 assuming the special continuum hypothesis CH. Moreover, in Gödel’s constructible universe we prove that this characterizes CG for arbitrary torsion-free abelian G. It follows that there exists some ugly N1-free abelian groups.

Original languageEnglish
Pages (from-to)1617-1626
Number of pages10
JournalRocky Mountain Journal of Mathematics
Volume32
Issue number4
DOIs
StatePublished - 2002

Fingerprint

Dive into the research topics of 'Cotorsion theories cogenerated by N1-free abelian groups'. Together they form a unique fingerprint.

Cite this