Tien Yien Li

Dr. Tien-Yien Li passed away peacefully on June 25, 2020, at the age of 75. Li, of Hunan ancestry, was born in June 1945 in Sa County in the Fujian Province of China. He earned his B.S. in Mathematics at the Taiwan National Tsinghua University in 1968. He came to the United States to pursue his love of Mathematics at the University of Maryland at College Park. He received his doctorate in 1974 under the guidance of Dr. James Yorke.

Li was previously married to Jacqueline Chen and they had one son together, Edward Li. Jackie and Li remained close friends after their divorce and Li did not remarry. He is survived by Jackie (The Villages, FL), Edward and his wife Juanita (Highland, MD), his two grandchildren Owen and Julia, his two brothers Jian-Chen (Taipei) and Ling-Fong (Sacramento, CA) and his two sisters Mei-Feng (Taipei) and Mei-Fong (Taipei).

Li received numerous honors and awards during his academic career. They include the highly prestigious Guggenheim Fellowship in 1995, Michigan State University’s Distinguished Faculty Award as well as Frame Teaching Award in 1996, Michigan State University’s Distinguished Professor Award in 1998, College of Sciences Distinguished Alumni Award of National Tsinghua University in Taiwan in 2002, Michigan State University College of Natural Science’s Outstanding Academic Advisor Award in 2006, and National Tsinghua University’s Outstanding Alumni Award in 2012. Li retired as a University Distinguished Professor Emeritus in 2018 after 42 years at the University.

Despite his numerous ailments, Li had been a trailblazer in several important fields of Applied Mathematics and Computational Mathematics. One of his many monumental accomplishments includes his paper with Yorke, “Period three implies chaos.” This paper has been cited more than 4800 times according to Google Scholar. It is the first to formally encapsulate the concept of chaos in the field of mathematics, and was credited by Professor Freeman Dyson (IAS) as “one of the immortal gems in the literature of mathematics” in the 2008 Einstein Lecture article “Birds and Frogs.” His proof of Ulam’s conjecture is another pioneering work in the computation of invariant measures of chaotic dynamical systems, which laid a foundation to the area of computational ergodic theory. His idea and numerical method with Kellogg and Yorke in computing Brouwer’s fixed point opened a new era for the research in modern homotopy continuation methods. Li’s extensive and deep research with his collaborators as well as his students on the algebraic eigenvalue problem and multivariate polynomial systems has earned him the honor of being one of the world’s leaders in the field.

Li supervised twenty-six Ph.D. dissertations in the general areas of Dynamical Systems and Numerical Analysis throughout his career. The challenges that he posed for students, his ideas and approaches to Mathematics research, as well as his courage and spirit of overcoming obstacles have and will continue to have profound impact on his students and colleagues.

Private family services will be held. Friends, family, and colleagues are invited to view the service on the funeral home Facebook page beginning Thursday, July 2 at 2pm, at https://www.facebook.com/Gorsline-Runciman-Funeral-Homes-163145830381110/

In lieu of flowers, memorial contributions may be made to the National Kidney Foundation, Finance Department, 30 East 33rd St., New York, NY 10016.

Online condolences may be expressed at www.greastlansing.com