Some Basic Results on Actions of Non-affine Algebraic Groups
نویسنده
چکیده
We study actions of connected algebraic groups on normal algebraic varieties, and show how to reduce them to actions of affine subgroups. This yields a structure theorem for normal equivariant embeddings of semi-abelian varieties, and a characteristic-free version of the Borel–Remmert theorem.
منابع مشابه
Algebraic Groups: Part Ii
4. Constructible sets 17 5. Connected components 18 6. Subgroups 20 7. Group actions and linearity versus affine 22 7.1. 24 8. Jordan Decomposition 27 8.1. Recall: linear algebra 27 8.2. Jordan decomposition in linear algebraic groups 30 9. Commutative algebraic groups 35 9.1. Basic decomposition 35 9.2. Diagonalizable groups and tori 35 9.2.1. Galois action 39 9.3. Action of tori on affine var...
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تاریخ انتشار 2008