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arXiv · 1011.2169

Separating invariants for the basic G_a-actions

Jonathan Elmer·Martin Kohls
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Abstract

We explicitly construct a finite set of separating invariants for the basic $\Ga$-actions. These are the finite dimensional indecomposable rational linear representations of the additive group $\Ga$ of a field of characteristic zero, and their invariants are the kernel of the Weitzenböck derivation $D_{n}=x_{0}\frac{\partial}{\partial{x_{1}}}+...+ x_{n-1}\frac{\partial}{\partial{x_{n}}}$.

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Jonathan Elmer, Martin Kohls. 2010-11-09. Separating invariants for the basic G_a-actions. https://doi.org/10.1090/s0002-9939-2011-11273-5

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