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arXiv · 2510.00391

Extensions Of Unirational Groups

Zev Rosengarten
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Abstract

We undertake a study of extensions of unirational algebraic groups. We prove that extensions of unirational groups are also unirational over fields of degree of imperfection $1$, but that this fails over every field of higher degree of imperfection, answering a question of Achet. We also initiate a study of those groups which admit filtrations with unirational graded pieces, and show that one may deduce unirationality of unipotent groups from unirationality of certain quotients.

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Zev Rosengarten. 2025-10-01. Extensions Of Unirational Groups. https://arxiv.org/abs/2510.00391

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