ar X iv : m at h / 01 06 08 1 v 1 [ m at h . A G ] 1 1 Ju n 20 01 EFFECTIVE DESCENT MAPS FOR SCHEMES
نویسنده
چکیده
I show that a quasicompact morphism f : X → Y of schemes is an effective descent map for quasicoherent modules if and only if the map OY → f∗(OX) is injective, and remains injective after any base change. This generalizes Grothendieck’s result that faithfully flat quasicompact morphisms are effective descent maps.
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