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arXiv · 1312.4475

Almost split sequences for Knorr lattices

Andrew Poulton
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Abstract

Let $O$ be a complete d.v.r. and $G$ a finite group. We give two applications of an adjunction in the stable category of $OG$. The first application gives necessary and sufficient conditions for the middle term of an almost split sequence terminating in a Knorr lattice to be indecomposable. The second characterises the stable endomorphism rings of Heller lattices of kG-modules.

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Andrew Poulton. 2014-03-15. Almost split sequences for Knorr lattices. https://arxiv.org/abs/1312.4475

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