# NYU Courant Mourns the Loss of Professor Andrew J. Majda

Andrew Joseph Majda passed away on March 12, 2021 at the age of 72.

Renowned for both his theoretical contributions to partial differential equations and his applied work in diverse areas such as asymptotic methods, numerical methods, scattering theory, shock waves, combustion, incompressible flow, vortex motion, turbulent diffusion, and atmosphere ocean science, Andy Majda made a number of seminal contributions in mathematics and physics. One of the most notable is the Beal-Kato-Majda theorem, which limits the possibility for singularities in inviscid, incompressible fluid flow. Andy’s primary research interests were in modern applied mathematics in the broadest possible sense merging asymptotic methods, numerical methods, physical reasoning, and rigorous mathematical analysis.

Andy was born on January 30, 1949 in East Chicago, Indiana. He earned his Bachelor of Science degree in Mathematics from Purdue University (1970) and his Ph.D. in Mathematics from Stanford (1973). His doctoral dissertation was entitled “Coercive Inequalities for Nonelliptic Symmetric Systems.” Andy first joined the NYU Courant Mathematics Department as a Courant Instructor in 1973 and was here for just two years before moving on to faculty appointments at UCLA, UC Berkeley, and Princeton. NYU was a special place for Andy, and he returned in 1994 as the Samuel F. B. Morse Professor of Arts and Sciences in the Mathematics Department at Courant and remained here since then. He retired on January 1, 2021 and became Professor Emeritus of Mathematics.

As a pioneering theoretical and applied mathematician, Andy consistently received scientific recognition throughout his career. One of his earliest honors was as plenary speaker at the first ever International Council of Industrial and Applied Mathematics (ICIAM) in Paris in 1987. Most recently, in 2016, Andy received the Leroy P. Steele Prize for seminal contribution to research, which is awarded by the American Mathematical Society (AMS). He received the Lagrange Prize of ICIAM, the Norbert Wiener Prize of the AMS and the Society of Industrial and Applied Mathematics (SIAM), the National Academy of Sciences Prize in Applied Mathematics and Numerical Analysis, the John von Neumann Prize of SIAM, and the Gibbs Prize of the AMS. Andy was elected as a member of the National Academy of Sciences, a fellow of the American Academy of Arts and Sciences, and a fellow of both the AMS and SIAM. Twice he was awarded the Medal of the College de France, and he was elected as a Fellow of the Japan Society for the Promotion of Science. He received Honorary Doctorates from Fudan University, China Northwest University, and Purdue University, as well as The New York City Mayor's Award for Excellence in Mathematical, Physical, and Engineering Sciences.

In addition to his outstanding research, Andy was a devoted PhD advisor to thirty doctoral students, a mentor to over thirty postdoctoral researchers, and he inspired many collaborators and others in the mathematical sciences community. His published books include Compressible Fluid Flow and Systems of Conservation Laws in Several Space Variables (Springer-Verlag), Vorticity and Incompressible Flow with A. Bertozzi (Cambridge University Press), Lecture Notes for the Courant Lecture Note Series of the AMS. Other published works include the Introduction to PDE’s and Waves for the Atmosphere and Ocean, the CRM monograph series on Information Theory and Stochastics for Multiscale Nonlinear Systems, with M. Grote and R. Abramov, all published by the AMS, and Nonlinear Dynamics and Statistical Theories for Basic Geophysical Flows with Xiaoming Wang published by Cambridge University Press. His newest book with John Harlim, is entitled Filtering Complex Turbulent Systems and was published Cambridge University Press.

Andy made major contributions to NYU, locally here at the NYU New York campus and overseas. In his years at the Courant Institute, Andy created the Center for Atmosphere Ocean Science (CAOS) with eight multi-disciplinary faculty to promote cross-disciplinary research with modern applied mathematics in climate modeling and prediction. Later, he founded NYU Abu Dhabi’s Center for Prototype Climate Modeling and served as its head and Principal Investigator. More recently, Andy’s research interests included multi-scale multi-cloud modeling for the tropics, stochastic and statistical modeling for climate, and novel mathematical strategies for prediction and data assimilation in complex multi-scale systems.

Andy is survived by his wife of 46 years, Gerta Keller, who is a Professor of Paleontology and Geology in the Geosciences Department of Princeton University. Full of energy and ideas, Andy was greatly influential at the Courant Institute and in the math community and will be dearly missed by all of his colleagues and friends.