Abstract
Let M and N be two representations of an extended Dynkin quiver such that the orbit \({\mathcal{O}}_N\) of N is contained in the orbit closure \(\overline{{\mathcal{O}}}_M\) and has codimension two. We show that the pointed variety \((\overline{{\mathcal{O}}}_M, N)\) 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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Zwara, G. Codimension two singularities for representations of extended Dynkin quivers. manuscripta math. 123, 237–249 (2007). https://doi.org/10.1007/s00229-007-0093-3
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DOI: https://doi.org/10.1007/s00229-007-0093-3