Degree 2 cohomological invariants of linear algebraic groups
arXiv:2010.13842 · doi:10.1016/j.jpaa.2022.107059
Abstract
The paper deals with the cohomological invariants of smooth and connected linear algebraic groups over an arbitrary field. More precisely, we study degree invariants with coefficients , that is invariants taking values in the Brauer group. Our main tool is the étale cohomology of sheaves on simplicial schemes. We get a description of these invariants for \emph{every} smooth and connected linear groups, in particular for non reductive groups over an imperfect field.
29 pages, preprint