Essential Dimension of Involutions and Subalgebras
نویسنده
چکیده
We use theorems of N. Karpenko about the incompressibility of Severi Brauer varieties and quadratic Weil transfers of Severi Brauer varieties to compute the minimal number of parameters needed to define conjugacy classes of involutions of given type on division algebras of 2-primary index. Similarly we compute the minimal number of parameters needed to define conjugacy classes of étale subalgebras of given type and central simple subalgebras of given degree in division algebras of p-primary index.
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