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arXiv · 2101.10217

A Cluster tilting module for a representation-infinite block of a group algebra

Bernhard Böhmler·Rene Marczinzik
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Abstract

Let $G=SL(2,5)$ be the special linear group of $2 \times 2$-matrices with coefficients in the field with $5$ elements. We show that the principal block over a splitting field $K$ of characteristic two of the group algebra $KG$ has a $3$-cluster tilting module. This gives the first example of a representation-infinite block of a group algebra having a cluster tilting module and answers a question by Erdmann and Holm.

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BibTeXRIS

Bernhard Böhmler, Rene Marczinzik. 2021-01-25. A Cluster tilting module for a representation-infinite block of a group algebra. https://arxiv.org/abs/2101.10217

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