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Codimension two singularities for representations of extended Dynkin quivers

Grzegorz Zwara
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Abstract

Let M and N be two representations of an extended Dynkin quiver such that the orbit O_N of N is contained in the orbit closure \bar{O_M} and has codimension two. We show that the pointed variety $(\bar{O_M},N)$ is smoothly equivalent to a simple surface singularity of type A_n, or to the cone over a rational normal curve.

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Grzegorz Zwara. 2006-03-29. Codimension two singularities for representations of extended Dynkin quivers. https://arxiv.org/abs/math/0603683

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