Separating invariants for the basic 𝔾ₐ-actions

Elmer, Jonathan; Kohls, Martin

doi:10.1090/S0002-9939-2011-11273-5

Separating invariants for the basic ${\mathbb G}_{a}$-actions
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Proc. Amer. Math. Soc. 140 (2012), 135-146 Request permission

Abstract:

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

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