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arXiv · 1012.5346

Examples of degenerations of Cohen-Macaulay modules

Naoya Hiramatsu·Yuji Yoshino
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Abstract

We study the degeneration problem for maximal Cohen-Macaulay modules and give several examples of such degenerations. It is proved that such degenerations over an even-dimensional simple hypersurface singularity of type $(A_n)$ are given by extensions. We also prove that all extended degenerations of maximal Cohen-Macaulay modules over a Cohen-Macaulay complete local algebra of finite representation type are obtained by iteration of extended degenerations of Auslander-Reiten sequences.

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Naoya Hiramatsu, Yuji Yoshino. 2010-12-24. Examples of degenerations of Cohen-Macaulay modules. https://arxiv.org/abs/1012.5346

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