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arXiv · 1604.04070

The automorphism theorem and additive group actions on the affine plane

Shigeru Kuroda
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Abstract

Due to Rentschler, Miyanishi and Kojima, the invariant ring for a ${\bf G}_a$-action on the affine plane over an arbitrary field is generated by one coordinate. In this note, we give a new short proof for this result using the automorphism theorem of Jung and van der Kulk.

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Shigeru Kuroda. 2016-04-14. The automorphism theorem and additive group actions on the affine plane. https://arxiv.org/abs/1604.04070

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