-free cogenerators
Manfred Dugas
Baylor University, Waco, USADaniel Herden
Baylor University, Waco, USASaharon Shelah
The Hebrew University of Jerusalem, Israel and The State University of New Jersey, Piscataway, USA
![$\aleph_k$-free cogenerators cover](/_next/image?url=https%3A%2F%2Fcontent.ems.press%2Fassets%2Fpublic%2Fimages%2Fserial-issues%2Fcover-rsmup-volume-144.png&w=3840&q=90)
Abstract
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