was a

Japanese Japanese may refer to: * Something from or related to Japan, an island country in East Asia * Japanese language, spoken mainly in Japan * Japanese people, the ethnic group that identifies with Japan through ancestry or culture ** Japanese diaspor ...

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 ...

Early life

Iyanaga was born in

Tokyo Tokyo (; ja, 東京, , ), officially the Tokyo Metropolis ( ja, 東京都, label=none, ), is the capital and List of cities in Japan, largest city of Japan. Formerly known as Edo, its metropolitan area () is the most populous in the world, ...

, Japan on April 2, 1906. He studied at the

University of Tokyo , abbreviated as or UTokyo, is a public research university located in Bunkyō, Tokyo, Japan. Established in 1877, the university was the first Imperial University and is currently a Top Type university of the Top Global University Project b ...

from 1926 to 1929. He studied under

Teiji Takagi Teiji Takagi (高木貞治 ''Takagi Teiji'', April 21, 1875 – February 28, 1960) was a Japanese mathematician, best known for proving the Takagi existence theorem in class field theory. The Blancmange curve, the graph of a nowhere-differentiabl ...

. As an undergraduate, he published two papers in the ''Japanese Journal of Mathematics'' and the ''Proceedings of the Imperial Academy of Tokyo''. Both of his papers appeared in print in 1928. After completing his undergraduate degree in 1929, he stayed at Tokyo and worked under Takagi for his doctorate. He completed his

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

in mathematics 1931.

Years in Europe

In 1931, Iyanaga obtained a scholarship from the French government. He also went to Hamburg, Germany where he studied with

Austria Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...

n mathematician Emil Artin. In 1932, he attended the International Congress of Mathematicians in Zurich. During his time in Europe, he met with top mathematicians such as

Claude Chevalley Claude Chevalley (; 11 February 1909 – 28 June 1984) was a French mathematician who made important contributions to number theory, algebraic geometry, class field theory, finite group theory and the theory of algebraic groups. He was a foun ...

, Henri Cartan, and others.

Academic career

Iyanaga returned to Tokyo in 1934 and was appointed Assistant Professor at the

. From 1935 to 1939, he didn't publish any research papers. According to Iyanaga, it was because of the pressure of teaching and other business to which he was not accustomed. He managed to solve a question of Artin on generalizing the

principal ideal theorem In mathematics, the principal ideal theorem of class field theory, a branch of algebraic number theory, says that extending ideals gives a mapping on the class group of an algebraic number field to the class group of its Hilbert class field, wh ...

and this was published in 1939. Iyanaga did publish many papers which arose through several courses such as

algebraic topology Algebraic topology is a branch of mathematics that uses tools from abstract algebra to study topological spaces. The basic goal is to find algebraic invariants that classify topological spaces up to homeomorphism, though usually most classify ...

functional analysis Functional analysis is a branch of mathematical analysis, the core of which is formed by the study of vector spaces endowed with some kind of limit-related structure (e.g. inner product, norm, topology, etc.) and the linear functions defined o ...

, and

geometry Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is ...

, which he taught. He became professor at the University of Tokyo in 1942. It was during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

. Towards the end of the war, many Japanese cities were bombarded and he had to find refuge in the countryside. He was busy in editing textbooks from primary and secondary schools and he continued to give courses and organise seminars. After the end of the war, he joined the Science Council of Japan in 1947. He became a member of the Executive Committee of the International Mathematical Union in 1952. He was responsible for organizing the International Congress of Mathematicians in

Amsterdam Amsterdam ( , , , lit. ''The Dam on the River Amstel'') is the capital and most populous city of the Netherlands, with The Hague being the seat of government. It has a population of 907,976 within the city proper, 1,558,755 in the urban ar ...

in 1954, which he attended. He was President of the International Commission on Mathematical Instruction from 1957 to 1978. Iyanaga spent the year 1961-62 at the

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private university, private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park, Chicago, Hyde Park neighborhood. The University of Chic ...

. He became Dean of the faculty of Science at the University of Tokyo in 1965, a position he held until his retirement in 1967. After his retirement, he was a visiting professor during 1967-68 at the

University of Nancy A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United States, th ...

in France. From 1967 to 1977, he was a professor at

Gakushuin University is a private university in Mejiro, Toshima Ward, Tokyo. It was re-established after World War II as an affiliate of the Gakushūin School Corporation. The privatized successor to the original Gakushūin University (or "Peers School") was estab ...

in Tokyo.

Honors and awards

Iyanaga received several honors and awards for his work. He received the Rising Sun from Japan in 1976. He was elected a member of the

Japan Academy The Japan Academy ( Japanese: 日本学士院, ''Nihon Gakushiin'') is an honorary organisation and science academy founded in 1879 to bring together leading Japanese scholars with distinguished records of scientific achievements. The Academy is ...

in 1978. He received the

Légion d'honneur The National Order of the Legion of Honour (french: Ordre national de la Légion d'honneur), formerly the Royal Order of the Legion of Honour ('), is the highest French order of merit, both military and civil. Established in 1802 by Napoleon ...

in 1980.

Publications

* *

References

External links

* * {{DEFAULTSORT:Iyanaga, Shokichi 1906 births 2006 deaths 20th-century Japanese mathematicians 21st-century Japanese mathematicians Japanese centenarians Men centenarians Recipients of the Legion of Honour Recipients of the Order of the Rising Sun, 2nd class University of Tokyo alumni Academic staff of the University of Tokyo Academic staff of Nancy-Université Academic staff of Nagoya University