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arXiv · 1002.3040

Euler characteristic of quiver Grassmannians and Ringel-Hall algebras of string algebras

Nicolas Poettering
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Abstract

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 $C(A)$.

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Nicolas Poettering. 2010-02-16. Euler characteristic of quiver Grassmannians and Ringel-Hall algebras of string algebras. https://arxiv.org/abs/1002.3040

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