Annual Newsletter of the University of Wisconsin Math Department

Promotions to Associate Professor

Three Assistant Professors were promoted to Associate Professor with tenure this past year. They are Mikhail Feldman, Xianghong Gong, and Tonghai Yang.

Mikail Feldman received the PhD in mathematics from the University of California, Berkeley in 1994 where his thesis advisor was L. C. Evans. Before joining us as Assistant Professor in 1999, he spent two years as Lecturer at the University of Pennsylvania, one year as a Postdoctoral Fellow at the University of California, Berkeley, and two years as Ralph Boas Assistant Professor of Mathematics at Northwestern University. His research field is Nonlinear partial differential equations (including elliptic and parabolic equations and free boundary problems, variational problems, and geometric and variational evolution problems). According to colleagues Sigurd Angenent and Paul Rabinowitz, who acted as his mentors, Feldman ``has made broad, deep and original contributions to the analysis of nonlinear partial differential equations'' and ``has done excellent research on mass transport problems, sandpile dynamics, free boundary problems, and multidimensional transonic shocks.''

Mikhail's research contributions have been recognized through grants and many invited talks. Besides an NSF individual research grant, he is a co-PI on a Focused Research Grant in mass transport problems (with L. Caffarelli, M. Cullen, L. C. Evans, W. Gangbo, and R. McCann). In the fall of 2003, Dr. Feldman was a visiting member of the Fields Institute in Toronto. Other recent invitations include talks at the PDE meeting in Oberwolfach, the Workshop on Optimal Transportation and Nonlinear Dynamics Workshop at PIMS in Vancouver, and the International Conference on Optimal Transportation Theory and Applications in Pisa. Mikhail has been organizing our joint Applied Math/PDE seminar.

Xianghong Gong received the PhD in mathematics from the University of Chicago in 1994, under the direction of Sidney M. Webster. He spent the 1994-1995 academic year visiting the Institute for Advanced Study (Princeton). During 1995-1996 he had a post-doctoral position at the Mathematical Sciences Research Institute in Berkeley, California. He then spent three years as an Assistant Professor at the University of Michigan, and one year as an Assistant Professor at Oklahoma State University before joining our department in 2000.

Xianghong's field of research is complex analysis and dynamical systems. Our former colleague Franc Forstneric, now at the University of Ljubljana, says that ``Gong has solved several notoriously difficult problems regarding questions of convergence of normal forms in various types of complex-analytic and geometric problems.'' Xianghong's research achievements already establish him in the top small group of young mathematicians in his field. … Dr. Gong's mathematical research has been supported by NSF grants since 1997. Recent invitations include workshops on Geometric Analysis of PDE and Several Complex Variables in Brazil, Complex dynamics Conference in Michigan, and a series of lectures at Nanjing University in China. He was one of the organizers of the special session on Several Complex Variables at the recent AMS meeting in Madison.

Tonghai Yang received the PhD in mathematics from the University of Maryland in 1995; his thesis advisor was Stephen Kudla. Before joining us as Assistant Professor in 2000, Tonghai spent one year at the Institute for Advanced Study (Princeton), two years as Hildebrandt Research Assistant Professor at the University of Michigan, and three years as an Assistant Professor at the State University of New York at Stony Brook. During 1999-2000, he was an AMS Centennial Fellow at Harvard University.

Dr. Yang's research fields are Number Theory, Arithmetic Geometry, and Representation Theory. According to his mentor Ken Ono, Tonghai ``is a leading world expert on critical values of Hecke L-functions'' and ``has developed a beautiful theory in which these values are given as values of automorphic theta functions.'' He also says that Tonghai is ``actively engaged in an important and deep program on the Taylor expansions of Eisenstein series.''

Yang's research contributions have been recognized through grants and many invited talks. In addition to the AMS Centennial Fellowship, he has had continuous NSF support since 1997. Recent invitations include a talk at a Modular Forms meeting in Oberwolfach, a seminar talk at Harvard University, and a series of six lectures on CM abelian varieties and Hecke L-functions at the Morningside Center of Mathematics in Beijing. For several years, Tonghai has been organizing our Number Theory seminar.