Alex Unger

Friday 14th October, 3:05-4:00 PM, Carslaw 375

Structure of Endomorphism Algebras of Abelian Varieties II

At the beginning of this talk I will basically finish the talk from last week with the classification theorem for endomorphism algebras of abelian varieties and some examples to make everything a bit clearer. Then I will introduce CM-types on abelian varieties. One can show that for every CM-type there exists an ablian variety (over the complex numbers) of this CM-type, which is, however, not necessarily simple. Therefore, I will give a group-theoretic characterization of CM-types which will help us later to decide whether a CM-type is primitive (i.e. the corresponding abelian variety is simple) or not.