Richard Courant

Richard Courant was a German-American mathematician who made profound contributions to mathematical analysis, applied mathematics, and mathematical physics. A student of the renowned David Hilbert at the University of Göttingen, he became a central figure in the vibrant mathematical community there before the rise of Nazism forced his emigration. In the United States, he founded what would become the Courant Institute of Mathematical Sciences at New York University, establishing a world-leading center for applied mathematics and leaving an enduring legacy in both research and education.

Early life and education

Born in Lublinitz in Silesia, then part of the German Empire, Courant displayed early mathematical talent. He moved to Berlin and later to Zürich, working as a tutor to support himself before ultimately enrolling at the University of Göttingen in 1907. There, he studied under the influential figures David Hilbert and Felix Klein, immersing himself in the school's pioneering work in functional analysis and theoretical physics. He completed his Dr. phil. under Hilbert's supervision in 1910 with a dissertation on the Dirichlet's principle, a topic at the heart of potential theory. His education was interrupted by service in the Imperial German Army during World War I, where he was wounded.

Career and contributions

After the war, Courant returned to Göttingen, succeeding Carl Runge as a professor and later becoming director of its Mathematical Institute. He revitalized the institute, attracting brilliant scholars like Pavel Alexandrov and fostering groundbreaking work. His own research was wide-ranging, making seminal advances in the calculus of variations, partial differential equations, and the connections between pure mathematics and theoretical physics. With David Hilbert, he co-authored the influential textbook Methods of Mathematical Physics. Other key contributions include the Courant minimax principle in spectral theory and, with colleagues Kurt Friedrichs and Hans Lewy, the foundational Courant–Friedrichs–Lewy condition for the stability of numerical solutions to PDEs.

Courant Institute and legacy

Dismissed from his position under the Nuremberg Laws in 1933, Courant emigrated, briefly teaching at the University of Cambridge before settling permanently in the United States. In 1936, he joined the faculty of New York University, where he built a modest graduate program into a powerhouse of applied mathematics. This center was formally named the Courant Institute of Mathematical Sciences in 1964. Under his leadership, it became renowned for research in fluid dynamics, nonlinear waves, and computer science, influencing fields from aerospace engineering to molecular biology. The institute stands as his most tangible legacy, embodying his belief in the unity of mathematics and its applications.

Personal life and death

Courant married Nerina (Nina) Runge, daughter of mathematician Carl Runge, in 1919. They had four children. Known as a charismatic and determined leader, he was deeply affected by his forced exile from Germany but dedicated himself to building a new mathematical community in America. He maintained connections with European colleagues and was instrumental in aiding other refugee scholars. Richard Courant died of a stroke in New Rochelle, New York, in January 1972. His posthumously awarded National Medal of Science in 1979 recognized his lifetime of transformative achievement.

Selected works and publications

* Methods of Mathematical Physics (with David Hilbert, Vol. I 1924, Vol. II 1937) * Differential and Integral Calculus (Vol. I 1934, Vol. II 1936) * Supersonic Flow and Shock Waves (with K. O. Friedrichs, 1948) * Dirichlet's Principle, Conformal Mapping, and Minimal Surfaces (1950) * What is Mathematics? (with Herbert Robbins, 1941)