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arXiv · 1408.6698

Approximation of sheaves on algebraic stacks

David Rydh
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Abstract

Raynaud--Gruson characterized flat and pure morphisms between affine schemes in terms of projective modules. We give a similar characterization for non-affine morphisms. As an application, we show that every quasi-coherent sheaf is the union of its finitely generated quasi-coherent subsheaves on any quasi-compact and quasi-separated algebraic stack.

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David Rydh. 2015-09-30. Approximation of sheaves on algebraic stacks. https://doi.org/10.1093/imrn%2Frnv142

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