Triality and etale algebras
arXiv:0912.3405
Abstract
Trialitarian automorphisms are related to automorphisms of order 3 of the Dynkin diagram of type D4. Octic etale algebras with trivial discriminant, containing quartic subalgebras, are classified by Galois cohomology with value in the Weyl group of type D4. This paper discusses triality for such étale extensions.