Observable actions of algebraic groups
نویسندگان
چکیده
منابع مشابه
Observable Actions of Algebraic Groups Lex Renner and Alvaro Rittatore
Let G be an affine algebraic group and let X be an affine algebraic variety. An action G × X → X is called observable if for any G-invariant, proper, closed subset Y of X there is a nonzero invariant f ∈ k[X ] such that f | Y = 0. We characterize this condition geometrically as follows. The action G × X → X is observable if and only if (1) there is a nonempty open subset U ⊆ X consisting of clo...
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ژورنال
عنوان ژورنال: Transformation Groups
سال: 2009
ISSN: 1083-4362,1531-586X
DOI: 10.1007/s00031-009-9073-x