On indecomposable exceptional modules over gentle algebras

Abstract

We give a characterization of indecomposable exceptional modules over finite dimensional gentle algebras. As an application, we study gentle algebras arising from an unpunctured surface and show that a class of indecomposable modules related to curves without selfintersections, as exceptional modules, are uniquely determined by their dimension vectors.

24 pages, a conjecture which has been found wrong deleted, references and citations added