ArticleOriginal scientific text
Title
Representation theory of two-dimensionalbrauer graph rings
Authors 1
Affiliations
- Mathematisches Institut B/3, University of Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany
Abstract
We consider a class of two-dimensional non-commutative Cohen-Macaulay rings to which a Brauer graph, that is, a finite graph endowed with a cyclic ordering of edges at any vertex, can be associated in a natural way. Some orders Λ over a two-dimensional regular local ring are of this type. They arise, e.g., as certain blocks of Hecke algebras over the completion of at (p,q-1) for some rational prime . For such orders Λ, a class of indecomposable maximal Cohen-Macaulay modules (see introduction) has been determined by K. W. Roggenkamp. We prove that this list of indecomposables of Λ is complete.
Keywords
Brauer graph, order, Cohen-Macaulay, Auslander-Reiten quiver
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