Obituary: Assyr Abdulle

By Weinan E and Bjorn Engquist

Assyr Abdulle, a professor of mathematics at École polytechnique fédérale de Lausanne (EPFL), passed away on September 1, 2021. Assyr was a renowned numerical analyst who made numerous contributions to Runge-Kutta methods and multiscale modeling, with applications in biology, chemistry, materials science, geology, and medicine.

After obtaining a professional diploma in violin from the Geneva Conservatory of Music in 1993, Assyr earned a Ph.D. in mathematics from the University of Geneva in 2001. Upon graduation, he spent his first postdoctoral year with Princeton University’s Program in Applied and Computational Mathematics. Assyr then held positions as a research associate, assistant professor, and associate professor at ETH Zurich, the University of Basel, and the University of Edinburgh respectively. In 2009, he became a full professor at EPFL and chair of computational mathematics and numerical analysis.

While at EPFL, Assyr founded the master’s program in computational science and engineering and served as its director until his death. He was also the director of EPFL’s Mathematics in Computational Science and Engineering (MATHICSE) group (a position he held since 2016) and founding director of the Institute of Mathematics.

Assyr made fundamental contributions to numerical methods for multiscale partial differential equations, deterministic and stochastic dynamical systems, model reduction techniques, and Bayesian inverse problems for differential equations. He is especially known for his work on the heterogeneous multiscale method and the orthogonal Runge-Kutta-Chebyshev method for deterministic and stochastic multiscale dynamical systems.

Assyr received numerous accolades throughout his 50 years, including two notable awards from SIAM: the James H. Wilkinson Prize in Numerical Analysis and Scientific Computing in 2009 and the Germund Dahlquist Prize in 2013. He was also honored with SciCADE’s New Talent Award in 2005, an Advanced Research Fellowship by the Engineering and Physical Sciences Research Council in 2007, and EPFL’s Best Mathematics Section Teacher Award in 2015 and 2016.

Assyr was a kind person with a strong sense of community service. The applied mathematics community has lost a great colleague, an innovative contributor, and a competent organizer. He will be sorely missed.

Weinan E is a professor of mathematics at Peking University and Princeton University. He was Assyr Abdulle’s postdoctoral mentor at Princeton. Bjorn Engquist is a professor of mathematics at the University of Texas' Oden Institute for Computational Engineering and Sciences. He was a collaborator of Assyr Abdulle.