English

The Representation Type of the Descent Algebras

Representation Theory 2026-04-24 v1

Abstract

Schocker classified the representation type of the descent algebra of type A\mathbb{A} over any field of characteristic zero. In an earlier paper, the authors extended this classification for type A\mathbb{A} to fields of positive characteristic. In this paper, we complete the classification for all other types except for E8\mathbb{E}_8. The proof for type B\mathbb{B} is entirely theoretical, while some small cases in type D\mathbb{D} and the exceptional types require computer computation to determine their Ext-quivers.

Keywords

Cite

@article{arxiv.2604.21619,
  title  = {The Representation Type of the Descent Algebras},
  author = {Karin Erdmann and Kay Jin Lim},
  journal= {arXiv preprint arXiv:2604.21619},
  year   = {2026}
}