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arXiv · 1407.2363

Direct products of modules and the pure semisimplicity conjecture

Birge Huisgen-Zimmermann·Frank Okoh
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Abstract

It is shown that, if $R$ is either an Artin algebra or a commutative noetherian domain of Krull dimension $1$, then infinite direct products of $R$-modules resist direct sum decomposition as follows: If $(M_n)_{n \in \Bbb N}$ is a family of non-isomorphic, finitely generated, indecomposable $R$-modules, then $\prod_{n\in \Bbb N} M_n$ is not a direct sum of finitely generated modules. The bearing of this direct product condition on the pure semisimplicity problem is discussed.

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Birge Huisgen-Zimmermann, Frank Okoh. 2014-07-09. Direct products of modules and the pure semisimplicity conjecture. https://arxiv.org/abs/1407.2363

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