Professor Li Tatsien is one of the best specialists, worldwide, of the theory and numerical analysis of nonlinear hyperbolic partial differential equations, a domain where major difficulties abound, as well as a domain of fundamental importance in applications. These include in particular nonlinear elasticity and gas dynamics. For all his contributions to these fields, Professor Li has been elected to five national or international Academies, and he has received numerous prestigious awards and honors.
Guided by the objective of acquiring a better understanding of the theory and physics of shocks that occur in gas dynamics, Professor Li has developed a new theory of local existence of classical and discontinuous solutions for the most general quasi-linear hyperbolic systems with two variables, including those where a free boundary occurs. In this fashion, he was able to specify the local structure of discontinuous solutions. This pioneering work immediately attracted the attention of the best specialists of the subject.
In another series of fundamental contributions, Professor Li has established the existence of classical solutions for the Cauchy problem for general quasi-linear hyperbolic systems, with "sufficiently small" initial data. This work constitutes a double achievement: First, it provides optimal estimates of lower and upper bounds for the "life-span" of a classical solution; second, it can be applied to the system of nonlinear elastodynamics. The late Professor Jean Leray, one of the most famous mathematicians of the twentieth century, then made the following comment on this work: [quote] "The work of Li Tatsien provides precise and elegant answers to manifold questions raised by many researchers" [unquote]. More recently, Professor Li was able to obtain the first satisfactory mathematical modeling of "diagraphy of wells by resistivity", a method of fundamental importance in petroleum exploitation. This work led him to introduce a new family of boundary value problems, called "boundary value problems with equipotential surface". He then studied such problems, both theoretically and numerically, in particular by successfully applying homogenization theory to the modeling of an electrod composed of many parts. It is a measure of the success and power of his approach that it is currently used in more than ten petroleum fields over the world!
Professor Li is not only an eminent mathematician. During the past decades, he has been extremely influential in the development of the pure and applied mathematical community. In particular, a very far-sighted initiative was taken in 1998 by the late Jacques-Louis Lions, one of the most prominent applied mathematician of the twentieth century, and Professor Li, who together co-founded the ISFMA, the Institut Sino-Francais de Mathematiques Appliquees, or Chinese-French Institute of Applied Mathematics.

Thanks to the tireless efforts of Professor Li, this Institute, which is housed on the campus of Fudan University, has organized every year since 1998 highly successful Summer Schools, which have considerably contributed to the promotion and development of "modern" pure and applied mathematics in Asia and in the rest of the world.

Education

• Undergraduate Student, Department of Mathematics, Fudan University, 1953--1957.
• In-Service Graduate Student, Department of Mathematics, Fudan University,  1962--1966.
• Visiting Scholar, Collège de France, Paris, France,  1979 --1981.
  

Position

• Mathematician and Professor of Fudan University.
• Member, Chinese Academy of Sciences (1995---).
• Fellow, Academy of Sciences for the Developing World (1997---).
• Foreign Member, French Academy of Sciences (2005---).
• Member, European Academy of Sciences (2007---).
• Foreign Member, Portuguese Academy of Sciences (2008---).
• Chevalier de la Légion d’Honneur,  République Française (2008---).
• Docteur Honoris Causa, Université Paris 12–Val de Marne (2008---).
• Full Professor (1980---).
• Co-Director, Mathematical Center, Ministry of Education of China (1996---).
• Co-Director, Institut Sino-Français de Mathématiques Appliquées (ISFMA) (1998---).
• Director, Organizing Committee, China Undergraduate Mathematical Contest in Modeling (CUMCM) (1998---).
• Director, Directing Committee of Teaching on Mathematics and Statistics, Ministry of Education of China (2001---2013).
• Honorary President, China Society for Industrial and Applied Mathematics (CSIAM) (2008---).
• Dean, Graduate School of Fudan University (1991-- 1999).
• Vice-President, Shanghai Association for Science and Technology (1996---2006).
• Vice-President, Chinese Mathematical Society (1996--2003).
• Member, Conseil d'Enseignement of the Ecole Polytechnique (1997---2003).
• President, China Society for Industrial and Applied Mathematics (CSIAM) (2000---2008).
• Officer-at-large, International Council for Industrial and Applied Mathematics (ICIAM) (2003---2011). 
  

Research

1. Systematic study on the local solvability and the global regularity with applications for general quasilinear hyperbolic systems in two independent variables.
   
2. Complete result and unified framework on the global existence and the life-span of classical solutions to fully nonlinear wave equations (Li Tatsien, Chen Yunwei, Global Classical Solutions for Nonlinear Evolution Equations, Pitman Monographs and Surveys in Pure and Applied Mathematics 45, Longman Scientific & Technical, 1992).
   
3. Efficient mathematical model and methods on the resistivity well-logging and the spontaneous potential well-logging with  applications in petroleum exploitation.
   
4. Complete theory and efficient constructive framework on the exact controllability and observability for 1-D quasilinear hyperbolic systems (Li Tatsien, Controllability and Observability for Quasilinear Hyperbolic Systems, AIMS on Applied Mathematics 3, American Institute of Mathematical Sciences (AIMS) & Higher Education Press, 2010).
   

Publications

• Monographs and Text Books
• Proceedings of International Conference and Others
• Papers

Prizes and Awards

1. One Second Prize (1982) and one Third Prize (1997) of National Natural Science from the State.
2. One First Prize (1992) and two Second Prizes (1985, 1986) of Scientific and Technological Progress from the State Education Commission.
3. One First Prize (1987) of Scientific and Technological Progress from Shanghai Municipality .
4. Two textbooks are awarded as Excellent University Textbooks from the Sate (1987, 1996).
5. Two Exceptional Shanghai Award for Teaching Achievements in Higher Education (2005, 2009).
6. One First National Award for Teaching Achievements in Higher Education (2005).
7. Science and Technology Progress Award of Ho Leung Ho Lee Foundation (2005).
8. Hua Loo-Keng Prize of Mathematics (2007).
9. Shanghai Top Science and Technology Award (2007).
10. Su Buchin Prize of Applied Mathematics (2010).