When is a reductive group scheme linear?

2021/03/12 by Philippe Gille, Gille, Philippe
Mathematics · #Algebraic Geometry (math.AG) #FOS: Mathematics #Rings and Algebras (math.RA) #math.AG #math.RA

paper · pdf · doi:10.48550/arxiv.2103.07305

arxiv created 2021/04/22 · arxiv updated 2021/04/23

Abstract

We show that a reductive group scheme over a base scheme S admits a faithful linear representation if and only if its radical torus is isotrivial, that is, it splits after a finite étale cover.

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