Lötscher, Roland; MacDonald, Mark; Meyer, Aurel; Reichstein, Zinovy
(2013):
Essential dimension of algebraic tori.
In: Journal für die reine und angewandte Mathematik (Crelle's Journal), No. 677: pp. 1-13
|
![[img]](https://epub.ub.uni-muenchen.de/59543/1.hassmallThumbnailVersion/Loetscher_Essential_Dimension.pdf)  Preview |
|
155kB |
Abstract
The essential dimension is a numerical invariant of an algebraic group G which may be thought of as a measure of complexity of G-torsors over fields. A recent theorem of N. Karpenko and A. Merkurjev gives a simple formula for the essential dimension of a finite p-group. We obtain similar formulas for the essential p-dimension of a broad class of groups, which includes all algebraic tori.