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Singularities of orbit closures in module varieties and cones over rational normal curves

Grzegorz Zwara
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Abstract

Let $N$ be a point of an orbit closure $\bar{O_M}$ in a module variety such that its orbit $O_N$ has codimension two in $\bar{O_M}$. We show that under some additional conditions the pointed variety $(\bar{O_M},N)$ is smoothly equivalent to a cone over a rational normal curve.

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Grzegorz Zwara. 2005-07-28. Singularities of orbit closures in module varieties and cones over rational normal curves. https://arxiv.org/abs/math/0507593

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