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Integral models and torsors of inseparable forms of \(\mathbb{G}_a \). (English) Zbl 1502.14106

Summary: After recalling some basic facts about \(F\)-wound commutative unipotent algebraic groups over an imperfect field \(F\), we study their regular integral models over Dedekind schemes of positive characteristic and compute the group of isomorphism classes of torsors of one-dimensional groups.

MSC:

14L15 Group schemes
14G17 Positive characteristic ground fields in algebraic geometry
14J27 Elliptic surfaces, elliptic or Calabi-Yau fibrations
14J28 \(K3\) surfaces and Enriques surfaces
20G15 Linear algebraic groups over arbitrary fields
14J25 Special surfaces
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References:

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