Soit F un corps de caractéristique , et soit G un groupe algébrique fini étale sur F. On calcule la dimension essentielle de G en p, que l'on note . Plus précisément, on démontre que
Let F be a field of characteristic and G be a smooth finite algebraic group over F. We compute the essential dimension of G at p. That is, we show that
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@article{CRMATH_2018__356_5_463_0, author = {Reichstein, Zinovy and Vistoli, Angelo}, title = {Essential dimension of finite groups in prime characteristic}, journal = {Comptes Rendus. Math\'ematique}, pages = {463--467}, publisher = {Elsevier}, volume = {356}, number = {5}, year = {2018}, doi = {10.1016/j.crma.2018.03.013}, language = {en}, url = {http://archive.numdam.org/articles/10.1016/j.crma.2018.03.013/} }
TY - JOUR AU - Reichstein, Zinovy AU - Vistoli, Angelo TI - Essential dimension of finite groups in prime characteristic JO - Comptes Rendus. Mathématique PY - 2018 SP - 463 EP - 467 VL - 356 IS - 5 PB - Elsevier UR - http://archive.numdam.org/articles/10.1016/j.crma.2018.03.013/ DO - 10.1016/j.crma.2018.03.013 LA - en ID - CRMATH_2018__356_5_463_0 ER -
%0 Journal Article %A Reichstein, Zinovy %A Vistoli, Angelo %T Essential dimension of finite groups in prime characteristic %J Comptes Rendus. Mathématique %D 2018 %P 463-467 %V 356 %N 5 %I Elsevier %U http://archive.numdam.org/articles/10.1016/j.crma.2018.03.013/ %R 10.1016/j.crma.2018.03.013 %G en %F CRMATH_2018__356_5_463_0
Reichstein, Zinovy; Vistoli, Angelo. Essential dimension of finite groups in prime characteristic. Comptes Rendus. Mathématique, Tome 356 (2018) no. 5, pp. 463-467. doi : 10.1016/j.crma.2018.03.013. http://archive.numdam.org/articles/10.1016/j.crma.2018.03.013/
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☆ The authors are grateful to the Collaborative Research Group in Geometric and Cohomological Methods in Algebra at the Pacific Institute for the Mathematical Sciences for their support of this project.