A dual to Baer’s lemma
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- by Ulrich Albrecht and H. Pat Goeters PDF
- Proc. Amer. Math. Soc. 105 (1989), 817-826 Request permission
Abstract:
Let $A$ be an abelian group. We investigate the splitting of sequences $( * )\quad 0 \to P \to G \to H \to 0$ with $P\quad A$-projective: Examples show that restrictions on $G$ and $H$ must be imposed to obtain a dual to Baer’s Lemma. A characterization of the splitting of sequences like (*) where $G$ is $A$-reflexive and ${R_A}\left ( H \right ) = 0$ is given in terms of $A$ and $E\left ( A \right )$, when $A$ is slender and nonmeasurable. Furthermore, we consider related problems and present applications of our results.References
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Additional Information
- © Copyright 1989 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 105 (1989), 817-826
- MSC: Primary 20K40
- DOI: https://doi.org/10.1090/S0002-9939-1989-0963569-X
- MathSciNet review: 963569