Kurt Otto Friedrichs (September 28, 1901 – December 31, 1982) was a noted German-American
mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems.
Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change.
History
On ...
. He was the co-founder of the
Courant Institute
The Courant Institute of Mathematical Sciences (commonly known as Courant or CIMS) is the mathematics research school of New York University (NYU), and is among the most prestigious mathematics schools and mathematical sciences research cente ...
at
New York University
New York University (NYU) is a private research university in New York City. Chartered in 1831 by the New York State Legislature, NYU was founded by a group of New Yorkers led by then-Secretary of the Treasury Albert Gallatin.
In 1832, the ...
, and a recipient of the
National Medal of Science
The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social scienc ...
.
Biography
Friedrichs was born in
Kiel
Kiel () is the capital and most populous city in the northern Germany, German state of Schleswig-Holstein, with a population of 246,243 (2021).
Kiel lies approximately north of Hamburg. Due to its geographic location in the southeast of the J ...
,
Schleswig-Holstein
Schleswig-Holstein (; da, Slesvig-Holsten; nds, Sleswig-Holsteen; frr, Slaswik-Holstiinj) is the northernmost of the 16 states of Germany, comprising most of the historical duchy of Holstein and the southern part of the former Duchy of Sch ...
on September 28, 1901. His family soon moved to
Düsseldorf
Düsseldorf ( , , ; often in English sources; Low Franconian and Ripuarian: ''Düsseldörp'' ; archaic nl, Dusseldorp ) is the capital city of North Rhine-Westphalia, the most populous state of Germany. It is the second-largest city in th ...
, where he grew up. He attended several different universities in Germany studying the philosophical works of
Heidegger
Martin Heidegger (; ; 26 September 188926 May 1976) was a German philosopher who is best known for contributions to phenomenology, hermeneutics, and existentialism. He is among the most important and influential philosophers of the 20th centur ...
and
Husserl
, thesis1_title = Beiträge zur Variationsrechnung (Contributions to the Calculus of Variations)
, thesis1_url = https://fedora.phaidra.univie.ac.at/fedora/get/o:58535/bdef:Book/view
, thesis1_year = 1883
, thesis2_title ...
, but finally decided that mathematics was his real calling. During the 1920s, Friedrichs pursued this field in
Göttingen
Göttingen (, , ; nds, Chöttingen) is a college town, university city in Lower Saxony, central Germany, the Capital (political), capital of Göttingen (district), the eponymous district. The River Leine runs through it. At the end of 2019, t ...
, which had a renowned Mathematical Institute under the direction of
Richard Courant
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. His research focused on the areas of real ...
. Courant became a close colleague and lifelong friend of Friedrichs.
In 1931, Friedrichs became a full professor of mathematics at the
Technische Hochschule in Braunschweig. In early February 1933, a few days after
Hitler
Adolf Hitler (; 20 April 188930 April 1945) was an Austrian-born German politician who was dictator of Germany from 1933 until his death in 1945. He rose to power as the leader of the Nazi Party, becoming the chancellor in 1933 and then ...
became the
Chancellor of Germany
The chancellor of Germany, officially the federal chancellor of the Federal Republic of Germany,; often shortened to ''Bundeskanzler''/''Bundeskanzlerin'', / is the head of the federal government of Germany and the commander in chief of the Ge ...
, Friedrichs met and immediately fell in love with a young Jewish student, Nellie Bruell. Their relationship became increasingly challenging and difficult because of the anti-Semitic
Nuremberg Laws
The Nuremberg Laws (german: link=no, Nürnberger Gesetze, ) were antisemitic and racist laws that were enacted in Nazi Germany on 15 September 1935, at a special meeting of the Reichstag convened during the annual Nuremberg Rally of ...
of Hitler's government. In 1937, both Friedrichs and Nellie Bruell managed to emigrate separately to
New York City
New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the L ...
where they finally married. Their long and very happy marriage produced five children.
[Life of K. O. Friedrichs](_blank)
/ref>
Courant had left Germany in 1933 and had founded an institute for graduate studies in mathematics at New York University
New York University (NYU) is a private research university in New York City. Chartered in 1831 by the New York State Legislature, NYU was founded by a group of New Yorkers led by then-Secretary of the Treasury Albert Gallatin.
In 1832, the ...
. Friedrichs joined him when he arrived in 1937 and remained there for forty years. He was instrumental in the development of the Courant Institute of Mathematical Sciences
The Courant Institute of Mathematical Sciences (commonly known as Courant or CIMS) is the mathematics research school of New York University (NYU), and is among the most prestigious mathematics schools and mathematical sciences research cente ...
, which eventually became one of the most distinguished research institutes for applied mathematics in the world. Friedrichs died in New Rochelle, New York
New Rochelle (; older french: La Nouvelle-Rochelle) is a city in Westchester County, New York, United States, in the southeastern portion of the state. In 2020, the city had a population of 79,726, making it the seventh-largest in the state of ...
on December 31, 1982.
Friedrichs's greatest contribution to applied mathematics was his work on partial differential equations
In mathematics, a partial differential equation (PDE) is an equation which imposes relations between the various partial derivatives of a multivariable function.
The function is often thought of as an "unknown" to be solved for, similarly to ...
. He also did major research and wrote many books and papers on existence theory, numerical methods
Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of numerical methods th ...
, differential operators in Hilbert space
In mathematics, Hilbert spaces (named after David Hilbert) allow generalizing the methods of linear algebra and calculus from (finite-dimensional) Euclidean vector spaces to spaces that may be infinite-dimensional. Hilbert spaces arise natural ...
, non-linear buckling of plates, flows past wings, solitary waves, shock waves, combustion, magneto-fluid dynamical shock waves, relativistic flows, quantum field theory
In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. QFT is used in particle physics to construct physical models of subatomic particles and ...
, perturbation of the continuous spectrum, scattering theory, and symmetric hyperbolic equations. With Cartan, Friedrichs gave a "geometrized" formulation of Newtonian gravitation theory—also known
as “Newton–Cartan theory Newton–Cartan theory (or geometrized Newtonian gravitation) is a geometrical re-formulation, as well as a generalization, of Newtonian gravity first introduced by Élie Cartan and Kurt Friedrichs and later developed by Dautcourt, Dixon, Dombrowsk ...
”— and later developed by Dautcourt, Dixon, Dombrowski and Horneffer, Ehlers, Havas, Künzle, Lottermoser, Trautman, and others.
A member of the National Academy of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nati ...
since 1959, Friedrichs received many honorary degrees and awards for his work. There is a student prize named after Friedrichs at NYU
New York University (NYU) is a private research university in New York City. Chartered in 1831 by the New York State Legislature, NYU was founded by a group of New Yorkers led by then-Secretary of the Treasury Albert Gallatin.
In 1832, the ...
. The American Mathematical Society
The American Mathematical Society (AMS) is an association of professional mathematicians dedicated to the interests of mathematical research and scholarship, and serves the national and international community through its publications, meetings, ...
selected him as the Josiah Willards Gibbs lecturer for 1954. In November 1977, Friedrichs received the National Medal of Science
The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social scienc ...
from President Jimmy Carter "for bringing the powers of modern mathematics to bear on problems in physics, fluid dynamics, and elasticity."
Selected bibliography
*R. von Mises and K. O. Friedrichs, ''Fluid Dynamics'', Springer-Verlag (1971).
*K. O. Friedrichs, ''Perturbation of Spectra in Hilbert Space'', American Mathematical Society (1965).
*K. O. Friedrichs, ''Mathematical aspects of the quantum theory of fields'', Interscience (1953).
*K. O. Friedrichs, ''Spectral Theory of Operators in Hilbert Space'', Springer-Verlag (1981).
*. A selection from Friedrichs' works with a biography and commentaries of David Isaacson
David T. Isaacson is a United States Army major general who serves as the director of manpower and personnel of the Joint Staff since June 2022. He most recently served as the Chief of Staff of the United States Cyber Command
United State ...
, Fritz John
Fritz John (14 June 1910 – 10 February 1994) was a German-born mathematician specialising in partial differential equations and ill-posed problems. His early work was on the Radon transform and he is remembered for John's equation. He was a ...
, Tosio Kato
was a Japanese mathematician who worked with partial differential equations, mathematical physics and functional analysis.
Kato studied physics and received his undergraduate degree in 1941 at the Imperial University of Tokyo. After disruption o ...
, Peter Lax
Peter David Lax (born Lax Péter Dávid; 1 May 1926) is a Hungarian-born American mathematician and Abel Prize laureate working in the areas of pure and applied mathematics.
Lax has made important contributions to integrable systems, fluid ...
, Louis Nirenberg
Louis Nirenberg (February 28, 1925 – January 26, 2020) was a Canadian-American mathematician, considered one of the most outstanding mathematicians of the 20th century.
Nearly all of his work was in the field of partial differential equat ...
, Wolfgang Wasow, Harold Weitzner
Harold Weitzner is an American applied mathematician and physicist whose primary research is plasma physics. He is Professor Emeritus of Mathematics at the Courant Institute of Mathematical Sciences and has served as Director of the Magneto-Fluid ...
.
See also
*Mollifier
In mathematics, mollifiers (also known as ''approximations to the identity'') are smooth functions with special properties, used for example in distribution theory to create sequences of smooth functions approximating nonsmooth (generalized) f ...
References
External links
*
*
National Academy of Sciences Biographical Memoir
*
{{DEFAULTSORT:Friedrichs, Kurt O.
1901 births
1982 deaths
Scientists from Kiel
Scientists from New Rochelle, New York
20th-century German mathematicians
20th-century American mathematicians
National Medal of Science laureates
Members of the United States National Academy of Sciences
PDE theorists
Operator theorists
Courant Institute of Mathematical Sciences faculty
Technical University of Braunschweig faculty
Mathematicians from New York (state)
German emigrants to the United States