An orbit closure for a representation of the Kronecker quiver with bad singularities
Tom 97 / 2003
Colloquium Mathematicum 97 (2003), 81-86 MSC: 14B05, 14L30, 16G20. DOI: 10.4064/cm97-1-8
We give an example of a representation of the Kronecker quiver for which the closure of the corresponding orbit contains a singularity smoothly equivalent to the isolated singularity of two planes crossing at a point. Therefore this orbit closure is neither Cohen–Macaulay nor unibranch.