A solution to the Baer splitting problem

Angeleri Hügel, Lidia; Bazzoni, Silvana; Herbera, Dolors

doi:10.1090/S0002-9947-07-04255-9

A solution to the Baer splitting problem
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by Lidia Angeleri Hügel, Silvana Bazzoni and Dolors Herbera PDF

Trans. Amer. Math. Soc. 360 (2008), 2409-2421 Request permission

Abstract:

Let $R$ be a commutative domain. We prove that an $R$-module $B$ is projective if and only if $\mathrm {Ext}_R^1(B,T)=0$ for any torsion module $T$. This answers in the affirmative a question raised by Kaplansky in 1962.

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