Proceedings of the Japan Academy, Series A, Mathematical Sciences
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On an analog of Serre’s conjectures, Galois cohomology and defining equation of unipotent algebraic groups

Nguyêñ Quôć Thǎńg and Nguyêñ Duy Tân
Source: Proc. Japan Acad. Ser. A Math. Sci. Volume 83, Number 7 (2007), 93-98.

Abstract

In this note we establish the validity, in the case of unipotent group schemes over non-perfect fields, of an analog of Serre’s conjectures for algebraic groups, which relates properties of Galois (or flat) cohomology of unipotent group schemes to finite extensions of non-perfect fields. We also establish an interesting property of Russell’s defining equations of connected smooth one-dimensional unipotent groups over a field $k$.

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Primary Subjects: 11E72
Secondary Subjects: 12F05, 12F15, 20G10
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Links and Identifiers

Permanent link to this document: http://projecteuclid.org/euclid.pja/1200672007
Digital Object Identifier: doi:10.3792/pjaa.83.93
Mathematical Reviews number (MathSciNet): MR2361418
Zentralblatt MATH identifier: 1190.11028

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Proceedings of the Japan Academy, Series A, Mathematical Sciences

Proceedings of the Japan Academy, Series A, Mathematical Sciences