# Richard Courant (nonfiction)

**Richard Courant**(January 8, 1888 – January 27, 1972) was a German American mathematician. He is best known by the general public for the book

*What is Mathematics?*, co-written with Herbert Robbins.

Courant was born in Lublinitz, in the Prussian Province of Silesia. His parents were Siegmund Courant and Martha Courant née Freund of Oels. Edith Stein was Richard's cousin on the paternal side. During his youth his parents moved often, including to Glatz, then to Breslau and in 1905 to Berlin. He stayed in Breslau and entered the university there, then continued his studies at the University of Zürich and the University of Göttingen. He became David Hilbert's assistant in Göttingen and obtained his doctorate there in 1910. He was obliged to serve in World War I, but was wounded shortly after enlisting and therefore dismissed from the military. He continued his research in Göttingen and then engaged a two-year period at the University of Münster as professor of mathematics. There he founded the Mathematical Institute, which he headed as director from 1928 until 1933.

Courant left Germany in 1933, earlier than many Jewish escapees. He did not lose his position due to being Jewish, as his previous service as a front-line soldier exempted him; however, his public membership in the social-democratic left was reason enough (for the Nazis) for dismissal.

In 1936, after one year at Cambridge, Courant accepted a professorship at New York University in New York City. There he founded an institute for graduate studies in applied mathematics. The Courant Institute of Mathematical Sciences (as it was renamed in 1964) is now one of the most respected research centers in applied mathematics.

Courant and David Hilbert authored the influential textbook *Methoden der mathematischen Physik* which, with its revised editions, is still current and widely used since its publication in 1924. With Herbert Robbins he coauthored a popular overview of higher mathematics, intended for the general public, titled *What is Mathematics?*. With Fritz John he also coauthored the two-volume work *Introduction to Calculus and Analysis*, first published in 1965.

Courant's name is also attached to the finite element method, with his numerical treatment of the plain torsion problem for multiply-connected domains, published in 1943. This method is now one of the ways to solve partial differential equations numerically. Courant is a namesake of the Courant–Friedrichs–Lewy condition and the Courant minimax principle.

Courant died in New Rochelle, New York.

Commenting upon his analysis of experimental results from in-laboratory soap film formations, Courant believed that the existence of a physical solution does not obviate mathematical proof:

Empirical evidence can never establish mathematical existence--nor can the mathematician's demand for existence be dismissed by the physicist as useless rigor. Only a mathematical existence proof can ensure that the mathematical description of a physical phenomenon is meaningful.

## In the News

## Fiction cross-reference

## Nonfiction cross-reference

- Herbert Busemann (nonfiction) - Doctoral student
- William Feller (nonfiction) - Doctoral student
- Kurt Friedrichs (nonfiction) - Doctoral student
- David Hilbert (nonfiction) - Doctoral advisor
- Fritz John (nonfiction) - Doctoral student
- Joseph Keller (nonfiction) - Doctoral student
- Edgar Krahn (nonfiction) - Doctoral student
- Martin Kruskal (nonfiction) - Doctoral student
- Anneli Lax (nonfiction) - Doctoral student
- Hans Lewy (nonfiction) - Doctoral student
- Mathematics (nonfiction)
- Otto Neugebauer (nonfiction) - Doctoral student
- Franz Rellich (nonfiction) - Doctoral student

External links:

- Richard Courant @ Wikipedia