-free cogenerators

  • Manfred Dugas

    Baylor University, Waco, USA
  • Daniel Herden

    Baylor University, Waco, USA
  • Saharon Shelah

    The Hebrew University of Jerusalem, Israel and The State University of New Jersey, Piscataway, USA
$\aleph_k$-free cogenerators cover
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We prove in ZFC that an abelian group is cotorsion if and only if Ext for every -free group , and discuss some consequences and related results. This short note includes a condensed overview of the -Black Box for -free constructions in ZFC.

Cite this article

Manfred Dugas, Daniel Herden, Saharon Shelah, -free cogenerators. Rend. Sem. Mat. Univ. Padova 144 (2020), pp. 87–104

DOI 10.4171/RSMUP/58