时间：2024年11月29日（星期五）14:00-15:45

Time: 14:00-15:45, Friday, November 29 2024

地点/Venue：E10-211

主讲人/Speaker: Sinnou David, University Pierre et Marie Curie

主讲人简介/Biography: Sinnou David joined the faculty of the University Pierre et Marie Curie, Paris in 1989 as a Maître de Conférences and then as a professor in 2006.

He is specialized in Diophantine geometry and among his main contribution, one can mention: - in Baker's theory, with a full solution of a conjecture of S. Lang on values of rational functions of elliptic curves;

-in height theory, a full solution on a generalized conjecture of Bogomolov on the height of

subvarieties of semi-abelian group schemes;

-in height theory again an almost optimal solution of Lehmer's problem in dimension at least two (the only previously known case being the dimension one).

-on the arithmetic of function fields the first cases of quadratic independence of periods of Drinfel'd modules.

讲座主题/Title：Small points and unit groups

讲座摘要/Abstract: We discuss progress towards conjectures of Bertrand and Villegas on arithmetic properties of subgroups of units of a number field, suggesting that one can expect lower bounds interpolating from the question of Lehmer (one dimensional subgroups) all the way up to lower bounds for the regulator (full unit group).