Prof. Dr. Chun Yin Hui (The University of Hongkong)

Abstract: Let X be an abelian variety or a K3 surface defined over a number field K. We prove that the density of the supersingular primes of X/K is zero if X is non-CM. By applying an effective Chebotarev density theorem of Serre, we obtain asymptotic upper bounds of the counting function for these supersingular primes.