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arXiv · 1907.12587

On extensions of algebraic groups

Mathieu Florence·Giancarlo Lucchini Arteche
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Abstract

We extend to the context of algebraic groups a classic result on extensions of abstract groups relating the set of isomorphism classes of extensions of $G$ by $H$ with that of extensions of $G$ by the center $Z$ of $H$. The proof should be easily generalizable to other contexts. We also study the subset of classes of split extensions and give a quick application by proving a finiteness result on these sets over a finite field.

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Mathieu Florence, Giancarlo Lucchini Arteche. 2020-01-28. On extensions of algebraic groups. https://arxiv.org/abs/1907.12587

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