was a Japanese

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 ...

who for over three decades was on the faculty at

Johns Hopkins University Johns Hopkins University (Johns Hopkins, Hopkins, or JHU) is a private research university in Baltimore, Maryland. Founded in 1876, Johns Hopkins is the oldest research university in the United States and in the western hemisphere. It consi ...

. He is known for his contributions to algebraic geometry and

number theory Number theory (or arithmetic or higher arithmetic in older usage) is a branch of pure mathematics devoted primarily to the study of the integers and integer-valued functions. German mathematician Carl Friedrich Gauss (1777–1855) said, "Mat ...

. The Igusa zeta-function, the

Igusa quartic In algebraic geometry, the Igusa quartic (also called the Castelnuovo–Richmond quartic ''CR''4 or the Castelnuovo–Richmond–Igusa quartic) is a quartic hypersurface in 4-dimensional projective space, studied by . It is closely related to the ...

, Igusa subgroups, Igusa curves, and Igusa varieties are named after him. He was an invited speaker for the 1962 International Congress of Mathematicians in Stockholm. He was awarded Japan's Order of the Sacred Treasure. In 2012 he became a fellow of 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, ...

Life and career

Igusa was born in Kiyosato village,

Gunma Prefecture is a Prefectures of Japan, prefecture of Japan located in the Kantō region of Honshu. Gunma Prefecture has a population of 1,937,626 (1 October 2019) and has a geographic area of 6,362 Square kilometre, km2 (2,456 Square mile, sq mi). Gunma P ...

, Japan, on 30 January 1924. He graduated from 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 ...

in 1945 and received 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 ...

from Kyoto University in 1953, after which he became professor of mathematics at the

University of Tsukuba is a public research university located in Tsukuba, Ibaraki, Japan. It is a top 10 Designated National University, and was ranked Type A by the Japanese government as part of the Top Global University Project. The university has 28 colle ...

. After a brief period spent at

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of high ...

, he took up a permanent position at Johns Hopkins University, in

Baltimore Baltimore ( , locally: or ) is the List of municipalities in Maryland, most populous city in the U.S. state of Maryland, fourth most populous city in the Mid-Atlantic (United States), Mid-Atlantic, and List of United States cities by popula ...

. Igusa taught at Johns Hopkins from 1955 to 1993. He joined the staff of the ''

American Journal of Mathematics The ''American Journal of Mathematics'' is a bimonthly mathematics journal published by the Johns Hopkins University Press. History The ''American Journal of Mathematics'' is the oldest continuously published mathematical journal in the United S ...

'' as an associate editor in 1964, and served as chief editor between 1978 and 1993. Igusa died, aged 89, of a stroke at Holly Hill Nursing Home in

Towson, Maryland Towson () is an unincorporated community and a census-designated place in Baltimore County, Maryland, United States. The population was 55,197 as of the 2010 census. It is the county seat of Baltimore County and the second-most populous unincor ...

, on 24 November 2013. He had three sons, Kiyoshi, Takeru and Mitsuru. Takeru Igusa is a professor of civil engineering at

. Kiyoshi Igusa is a professor of mathematics at

Brandeis University , mottoeng = "Truth even unto its innermost parts" , established = , type = Private research university , accreditation = NECHE , president = Ronald D. Liebowitz , ...

Publications

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References

1924 births 2013 deaths 20th-century Japanese mathematicians 21st-century Japanese mathematicians Kyoto University alumni Johns Hopkins University faculty Fellows of the American Mathematical Society Japanese expatriates in the United States Academic journal editors Recipients of the Order of the Sacred Treasure, 3rd class University of Tokyo alumni People from Gunma Prefecture Academic staff of the University of Tsukuba Harvard University Department of Mathematics faculty Harvard University faculty {{Japan-scientist-stub