Direct images of bundles under Frobenius morphism
نویسندگان
چکیده
منابع مشابه
Direct Images of Bundles under Frobenius Morphism
Let X be a smooth projective variety of dimension n over an algebraically closed field k with char(k) = p > 0 and F : X → X1 be the relative Frobenius morphism. For any vector bundle W on X , we prove that instability of F∗W is bounded by instability of W ⊗ T(Ω X ) (0 ≤ l ≤ n(p − 1))(Corollary 4.8). When X is a smooth projective curve of genus g ≥ 2, it implies F∗W being stable whenever W is st...
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Let X be a smooth projective variety over an algebraically field k with char(k) = p > 0 and F : X → X1 be the relative Frobenius morphism. When dim(X) = 1, we prove that F∗W is a stable bundle for any stable bundle W (Theorem 2.3). As a step to study the question for higher dimensional X , we generalize the canonical filtration (defined by Joshi-Ramanan-Xia-Yu for curves) to higher dimensional ...
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1.1. Injective resolutions. Let C be an abelian category. An object I ∈ C is injective if the functor Hom(−, I) is exact. An injective resolution of an object A ∈ C is an exact sequence 0→ A→ I → I → . . . where I• are injective. We say C has enough injectives if every object has an injective resolution. It is easy to see that this is equivalent to saying every object can be embedded in an inje...
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ژورنال
عنوان ژورنال: Inventiones mathematicae
سال: 2008
ISSN: 0020-9910,1432-1297
DOI: 10.1007/s00222-008-0125-y