%0 Journal Article
%T Euler characteristic of quiver Grassmannians and Ringel-Hall algebras of string algebras
%A Nicolas Poettering
%J Mathematics
%D 2010
%I arXiv
%X We compute the Euler characteristics of quiver Grassmannians and quiver flag varieties of tree and band modules and prove their positivity. This generalizes some results by G.C. Irelli [arXiv:0910.2592]. As an application we consider the Ringel-Hall algebra $C(A)$ of some string algebras $A$ and compute in combinatorial terms the products of arbitrary functions in $C(A)$.
%U http://arxiv.org/abs/1002.3040v1