Automorphisms of a Chevalley group of type G_2 over a commutative ring R with 1/3 generated by the all invertible elements and 2R

Abstract

In this paper we prove that every automorphism of a Chevalley group with the root system G_2 over a commutative ring R with 1/3, generated by all its invertible elements and the ideal 2R is a composition of ring and inner automorphisms.

arXiv comment14 pages, 1 figure. arXiv admin note: substantial text overlap with arXiv:1108.0529, arXiv:2304.13447