Automorphisms of Chevalley groups of types $A_l, D_l, E_l$ over local rings without 1/2

TL;DR

This paper proves that all automorphisms of certain Chevalley groups over local rings without 1/2 are standard, meaning they can be expressed as compositions of well-understood automorphisms.

Contribution

It establishes that automorphisms of Chevalley groups of types A_l, D_l, E_l over local rings without 1/2 are all standard, extending previous results to these types.

Findings

All automorphisms are standard automorphisms.

Automorphisms decompose into ring, inner, central, and graph automorphisms.

Results apply to Chevalley groups of types A_l, D_l, E_l over specified rings.

Abstract

In the given paper we prove that every automorphism of a Chevalley group of type $A_l$, $D_l$, or $E_l$, $l\geqslant 3$, over a commutative local ring without 1/2 is standard, i. e., it is a composition of ring, inner, central and graph automorphisms.