Sergiu Klainerman, Ph.D.

Sergiu Klainerman is Higgins professor of mathematics at Princeton University. He re- ceived his undergraduate degree from Bucharest University, Romania, and his PhD from New York University (1978). He was a Miller fellow at Bekeley (1978-1980) and returned to NYU in 1980 as an assistant professor. He joined the Princeton mathematics de- partment in 1987. He is a member of the U.S. National Academy of Sciences Sciences, fellow of the American Academy of Arts and Sciences and the American Mathematics Society, and Foreign Member of the French Academy of Sciences. He is the recipient of the MacArthur Fellowship award(1991), Bocher prize of AMS (1999) and Le Conte Prize of the French Academy of Sciences (1996). He is an editor for various journals such as Annals of Mathematics and Annals of PDE.

Klainerman has made important contributions to the study of nonlinear wave equations in continuum mechanics, relativistic field theories and General Relativity (GR). His early work is best known for the introduction of the vectorfield method and the null condition, both influential tools for the study of long time behavior of solutions to nonlinear sys- tems of wave equations. Together with D. Christodoulou he proved the global nonlinear stability of the Minkowski space, a foundational result in mathematical GR. Together with I. Rodnianski and J. Szeftel he proved the difficult and deep Bounded L2 Curva- ture Theorem, the best known continuation criterion in GR. Together with A. Ionescu, and later with S. Alexakis, he established the first smooth rigidity result of Kerr black holes. Together with I. Rodnianski and J. Luk he proved far reaching extensions of D. Christodoulou’s famous result on the formation of black holes. In collaborations with J. Szeftel, he made decisive contributions on the the well known Kerr stability problem, first by proving the global stability of Schwarzschild under polarized perturbations and, recently, by extending the result to unconditional perturbations of slowly rotating Kerr black holes. His most recent work- a sequence of 5 long papers- three in collaboration with J. Szeftel and the other two with E. Giorgi and D. Shen provides the first proof of the nonlinear stability of Kerr black holes for small angular momentum. The conjecture has been a major focus of interest in General Relativity ever since their dramatic discovery by Roy Kerr in 1963.