9 N ov 1 99 8 The GIT - equivalence for G - line bundles
نویسنده
چکیده
X(L) = {x ∈ X(L) such that Gx is finite and G · x is closed in X (L)} , where Gx is the stabilizer of x. It turns out that π −1 (π(x)) = G · x, for all x ∈ X(L). We refer to [7] or [8] for the classical properties of this quotient. Observe that this GIT-quotient is not canonical: it depends on a choice of an ample G-linearized line bundle L over X (sometimes called a polarization of X). During the last ten years, the question of variation of quotient X(L)//G under change of the ample G−linearized line bundle L has been
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