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arXiv · 1108.0529

Automorphisms of Chevalley groups of different types over commutative rings

Elena Bunina
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Abstract

In this paper we prove that every automorphism of (elementary) adjoint Chevalley group with root system of rank $>1$ over a commutative ring (with 1/2 for the systems $A_2$, $F_4$, $B_l$, $C_l$; with 1/2 and 1/3 for the system $G_2$) is standard, i.\,e., it is a composition of ring, inner, central and graph automorphisms.

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Elena Bunina. 2011-08-02. Automorphisms of Chevalley groups of different types over commutative rings. https://arxiv.org/abs/1108.0529

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