On the complement of the dense orbit for a quiver of type $\Aa$

Karin Baur; Lutz Hille

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arXiv · 1005.1919

On the complement of the dense orbit for a quiver of type $\Aa$

Karin Baur·Lutz Hille

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Abstract

Let $\Aa_t$ be the directed quiver of type $\Aa$ with $t$ vertices. For each dimension vector $d$ there is a dense orbit in the corresponding representation space. The principal aim of this note is to use just rank conditions to define the irreducible components in the complement of the dense orbit. Then we compare this result with already existing ones by Knight and Zelevinsky, and by Ringel. Moreover, we compare with the fan associated to the quiver $\Aa$ and derive a new formula for the number of orbits using nilpotent classes. In the complement of the dense orbit we determine the irreducible components and their codimension. Finally, we consider several particular examples.

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BibTeX RIS

Karin Baur, Lutz Hille. 2010-05-11. On the complement of the dense orbit for a quiver of type $\Aa$. https://arxiv.org/abs/1005.1919

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