Über erreichbare und baumartige unzerlegbare Darstellungen von Köchern
arXiv:1401.0721
Abstract
Let be a finite-dimensional algebra over an algebraically closed field. The problem of constructing indecomposable -modules inductively from simple ones by means of exact sequences - called accessibility - is the starting point of the present diploma-thesis. It has lead us to the consideration of exceptional and indecomposable tree-representations of finite quivers. Following Ringel, we prove his result that exceptional representations are tree-representations. We give a detailed description of the various aspects of the Schofield-Induction which plays an important role in the proof. Moreover we introduce a functor (strong hypotheses being given) which enables us to construct indecomposable modules of an algebra from indecomposable representations of a certain bipartite quiver. We also give a proof of Ringel's result that each exceptional representation of dimension of a generalized Kronecker quiver has an indecomposable factor- or subrepresentation of dimension . The thesis is concluded by some calculations showing the accessibility of representations of the 3-Kronecker-quiver in small dimensions.
Diploma Thesis, Bergische Universität Wuppertal 2012, 118 pages, in German, English title: "On accessible and indecomposable tree-representations of quivers"