English

Kronecker modules generated by modules of length 2

Representation Theory 2017-05-02 v2 Rings and Algebras

Abstract

Let Λ\Lambda be a ring and N\mathcal N a class of Λ\Lambda-modules. A Λ\Lambda-module is said to be generated by N\mathcal N provided that it is a factor module of a direct sum of modules in N\mathcal N. The semi-simple Λ\Lambda-modules are just the Λ\Lambda-modules which are generated by the Λ\Lambda-modules of length 1. It seems that the modules which are generated by the modules of length 22 (we call them bristled modules) have not attracted the interest they deserve. In this paper we deal with the basic case of the Kronecker modules, these are the (finite-dimensional) representations of an nn-Kronecker quiver, where nn is a natural number. We show that for n3n\ge 3, there is an abundance of bristled Kronecker modules.

Keywords

Cite

@article{arxiv.1612.07679,
  title  = {Kronecker modules generated by modules of length 2},
  author = {Claus Michael Ringel},
  journal= {arXiv preprint arXiv:1612.07679},
  year   = {2017}
}

Comments

25 pages. The main result is improved: it uses now the optimal number of n+2 bristles (not 2n-1, as the first version)

R2 v1 2026-06-22T17:32:34.657Z