数学科学研究所
Insitute of Mathematical Science

席南华 Nanhua Xi


Career

2022.11-Present      Vice President and Professor, ShanghaiTech University

2017.07-2022.11       President, Academy of Mathematics System Science, Chinese Academy of Science

2014.04-2017.10       Vice President, University of Chinese Academy of Sciences

2012.09-Present       Dean, School of Mathematical Sciences, University of Chinese Academy of Sciences

2012.04 -2017.07      Academic President, Academy of Mathematics System Science, Chinese Academy of Science

1990.01-Present       Research Assistant Professor, Research Associate Professor and Research  Professor (1994), Institute of Mathematics, CAS

1988.07-1989.12      Post-doc, Institute of Mathematics, Chinese Academy of Sciences

1981.07-1982.08      Teacher, Huang Xi Kou High School, Hunan Province



 Education

1978.10-1981.07      Huaihua Institute

1982.09-1985.07      East China Normal University, M.S. in Mathematics

1985.09-1988.07      East China Normal University, Ph.D. in Mathematics

 

Research

The primary research interests of Prof. Xi lie in algebraic groups and quantum groups. His research work includes a proof of Lusztig's conjecture on the based ring of a two-sided cell of an affine Weyl group of type A, confirming the necessary and sufficient conditions for validity of Deligne-Langlands conjecture for affine Hecke algebras. He proved that the properties of finite dimensional representations of a quantum group over a field of characteristic p>0 with parameter being a non-root of unity are similar to finite dimensional representations of an algebraic group over a field of characteristic 0 ; He gave a clear and explicit realization of  finite dimensional irreducible representation of a quantum group at a root of unity; He constructed monomial bases of quantum groups (joint with V. Chari), computed some canonical bases and established a commutation formula for root vectors. Joint with Lusztig he discovered canonical left cells in affine Weyl groups, and joint with Tanisaki he proved that a geometric filtration of an affine Hecke algebra of type A coincides with an algebraic filtration of the affine Hecke algebra. He initiated the study of infinite dimensional abstract representations of algebraic groups.


Selected Publications  

       1.Lusztig, G., Xi, N. (1988). Canonical left cells in affine Weyl groups. Adv. in Math., 72(2), 284-288.

       2.Xi, N.(1990). Finite dimensional modules of some quantum groups over Fp (v). J. Reine Angew. Math, 410, 109-115.

       3.Xi, N. (1994). Representations of affine Hecke algebras. Lecture Notes in Mathematics 1587Springer-Verlag.

       4.Xi, N. (1994). Root vectors in quantum groups, Comm. Math. Helv. 69 (1994), 612-639.

       5.Xi, N. (1996). Irreducible modules of quantized enveloping algebras at roots of 1. Publ. of the Research Inst. for Math. Sci., 32(2), 235-276.

       6.Chari, V., & Xi, N. (1999). Monomial bases of quantized enveloping algebras. Contemp. Math., 248, 69-82.

       7.Xi, N. (2002). The Based Ring of Two-Sided Cells of Affine Weyl Groups of Type A n-1Mem. of Amer. Math. Soc., Vol. 157, No. 749.

       8.Tanisaki, T., & Xi, N. (2006). Kazhdan-Lusztig basis and a geometric filtration of an affine Hecke algebra. Nagoya Math. J., 182, 285-311.

       9.Xi, N. (2007). Representations of affine Hecke algebras and based rings of affine Weyl groups. J. of  Ame. Math. Soc., 20(1), 211-217.

       10.Xi, N. (2014).Some infinite dimensional representations of reductive groups with Frobenius maps, Sci. China Math. 57 (2014), No. 6, 1109-1120. 

       11. Basic Algebra, Volume 1 and Volume 2. Published in 2016 and 2018 respectively, and intended for freshman of math major at the University of Chinese Academy of Sciences;  

            Basic Algebra, Volume 3.  Published in 2021 and intended for sophomore of math major at the University of Chinese Academy of Sciences.

 

 

Major Awards and Honors

2001    Morningside Silver Medal     

2005    The Chern Prize                   

2007    Second Prize of the National Natural Science Award                 

2009    Academician of Chinese Academy of Sciences                   

2021    Advanced individual of National teaching material construction 

 

Public Services

2018.03-2023.03          Member of the 13th Standing Committee of the National Committee of the Chinese People's Political Consultative Conference

2020.01-2023.12          Vice Chairman of the 13th Council of the Chinese Mathematical Society






地址:上海市浦东新区华夏中路393号
邮编:201210
上海市徐汇区岳阳路319号8号楼
200031(岳阳路校区)