Wenbo V. Li, professor of mathematical sciences at the University of Delaware, died suddenly of heart failure on January 26, 2013, near his home in Newark, Delaware. He was 49 years old.

Wenbo Li was born on October 27, 1963 in Harbin, China. After obtaining his Bachelor’s degree in applied mathematics from Jilin University in Changchun, China, he came to the United States in 1988 and studied probability theory at the University of Wisconsin–Madison, under the supervision of James Kuelbs. Wenbo Li obtained his PhD in mathematics in 1992 and accepted a position at the University of Delaware as an assistant professor, becoming an associate professor in 1996 and a full professor in 2002. At the time of his death, he was also an adjunct professor in Delaware’s Department of Electrical and Computer Engineering (since 2011) and Department of Applied Mathematics and Theoretical Physics (since 2007); a visiting professor at the Institute of Applied Mathematics of the Chinese Academy of Sciences (since 2005); and an adjunct professor at Harbin Institute of Technology, China (since 2006).

During his career as a research mathematician, Wenbo Li had also held visiting and other academic positions at various universities and research institutions, including Hong Kong University of Science and Technology, Peking University, the University of Pennsylvania, and Texas A&M University. He also served as an associate editor for several probability journals, including Annals of Probability, Journal of Theoretical Probability, Journal of Mathematical Research and Exposition, and International Journal of Stochastic Processes.

Wenbo Li was a probabilist who studied Gaussian measures and processes and published more than 70 research papers in these and related areas. He was a leading expert on small ball probability estimates: he contributed significantly to our understanding of the connection between the small ball probability and the entropy number. He worked for many years on the Gaussian correlation conjecture concerning a lower bound of the Gaussian measure of the intersection of two symmetric convex sets and was especially proud of a weak form of this conjecture that he proved. In 2006, he was elected a fellow of the IMS, “for his distinguished research in the theory of Gaussian processes and in using this theory to solve many important problems in diverse areas of probability.”

Besides his own research, Wenbo Li was very helpful to young researchers from China by hosting them in his department and working jointly with them to start their careers as research mathematicians.

Wenbo Li was a nature lover and enjoyed hiking in mountains in China and on the Great Wall. All his friends and acquaintances felt the immensity of his energy and his eagerness for activities. Wenbo Li is survived by his wife Sunny and his son James.

Elton P. Hsu, Northwestern University