Additive group actions on affine T-varieties of complexity one in arbitrary characteristic

Kevin Langlois; Alvaro Liendo

doi:10.1016/j.jalgebra.2015.11.019

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arXiv · 1408.1373

Additive group actions on affine T-varieties of complexity one in arbitrary characteristic

Kevin Langlois·Alvaro Liendo

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Abstract

Let X be a normal affine T-variety of complexity at most one over a perfect field k, where T stands for the split algebraic torus. Our main result is a classification of additive group actions on X that are normalized by the T-action. This generalizes the classification given by the second author in the particular case where k is algebraically closed and of characteristic zero. With the assumption that the characteristic of k is positive, we introduce the notion of rationally homogeneous locally finite iterative higher derivations which corresponds geometrically to additive group actions on affine T-varieties normalized up to a Frobenius map. As a preliminary result, we provide a complete description of these additive group actions in the toric situation.

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BibTeX RIS

Kevin Langlois, Alvaro Liendo. 2014-08-06. Additive group actions on affine T-varieties of complexity one in arbitrary characteristic. https://doi.org/10.1016/j.jalgebra.2015.11.019

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