The inverse Galois problem for connected algebraic groups

Michel Brion; Stefan Schröer

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arXiv · 2205.08117

The inverse Galois problem for connected algebraic groups

Michel Brion·Stefan Schröer

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Abstract

We show that each connected group scheme of finite type over an arbitrary ground field is isomorphic to the component of the identity inside the automorphism group scheme of some projective, geometrically integral scheme. The main ingredients are embeddings into smooth group schemes, equivariant completions, blow-ups of orbit closures, Fitting ideals for Kähler differentials, and Blanchard's Lemma.

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Michel Brion, Stefan Schröer. 2024-06-25. The inverse Galois problem for connected algebraic groups. https://arxiv.org/abs/2205.08117

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