Title: Some old and new results about singular moduli

Speaker： Prof. Dr. Yingkun Li (Technische Universität Darmstadt)

Time：14:30-16:00pm, Jan 6th, 2020(Monday)

Location：200-9，Sir Run Run Shaw Business Administration building

Abstract: The values of the modular j-invariant at CM points are called

singular moduli. They have been known to be algebraic integers since the

time of Kronecker and Weber. Recently, Bilu-Habegger-Kühne showed that these are not units. In this talk, we will apply the results of Gross-Zagier, Gross-Kohnen-Zagier and their generalizations to give a short proof of this result.

About the Speaker: Dr. Yingkun Li specializes in the area of number theory and automorphic forms, and is currently a Junior Professor Doctor in Technische Universität Darmstardt, Germany. He has wide interest in the theory of number fields and also modular forms from varying topics, and has made significant contributions to this area of research. In particular, Dr. Li has published numerously in top journals such as Duke Mathematical Journal, JEMS, Mathematische Annalen, Compositio Mathematica, and Algebra & Number Theory, etc.

Contact person：Gao Fan (gaofan@zju.edu.cn)