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arXiv · 1506.06082

Proper $G_a$-actions on $\C^4$ preserving a coordinate

Shulim Kaliman
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Abstract

We prove that the actions mentioned in the title are translations. We show also that for certain $G_a$-actions on affine fourfolds the quotient of the action is automatically affine and describe the geometric structure of such quotients.

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Shulim Kaliman. 2016-11-23. Proper $G_a$-actions on $\C^4$ preserving a coordinate. https://doi.org/10.2140/ant.2018.12.227

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