报告人简介：
De-Qi Zhang，新加坡国立大学数学系教授。华东师范大学学士, Osaka大学博士; Osaka大学助理教授; 1991年-至今: 新加坡国立大学 讲师, 高级讲师, 副教授; 教授.
荣誉：1) Yukawa Foundation award (1989) 2) Outstanding Scientist Award 2009, Science Faculty, NUS 3) Outstanding Mentor Award, October 2009, 15th Youth Science Conference, Singapore 4) One of Final Four shortlisted for President’s Science Award, yr 2010, Singapore.

报告内容简介：
Let G be a connected linear algebraic group over an algebraically closed field k, and let H be a connected closed subgroup of G. We prove that the homogeneous variety G/H is a rational variety over k whenever H is solvable or when dim(G/H) 10 and char(k) = 0. When H is of maximal rank in G, we also prove that G/H is rational if the maximal semisimple quotient of G is isogenous to a product of almost-simple groups of type A, type C (when char(k) > 2), or type B3 or G2 (when char(k) = 0).
This is a joint work with C. Chin.

主持人：谈胜利 教授