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arXiv · 2401.02006

Fiber criteria for flatness and homomorphisms of flat affine group schemes

Phùng Hô Hai·Hop D. Nguyen·João Pedro dos Santos
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Abstract

A very useful result concerning flatness in Algebraic Geometry is EGA's ``fiber'' criterion. We propose similar fiber criteria to verify flatness of a module while avoiding ``finiteness'' assumptions. Motivated by a Tannakian viewpoint (where the category of representations comes to the front), we derive applications to the theory of affine and flat group schemes.

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Phùng Hô Hai, Hop D. Nguyen, João Pedro dos Santos. 2024-01-04. Fiber criteria for flatness and homomorphisms of flat affine group schemes. https://arxiv.org/abs/2401.02006

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