Yoshie Katsurada (, 3 September 1911 – 10 May 1980) was a Japanese mathematician specializing in

differential geometry Differential geometry is a Mathematics, mathematical discipline that studies the geometry of smooth shapes and smooth spaces, otherwise known as smooth manifolds. It uses the techniques of Calculus, single variable calculus, vector calculus, lin ...

. She became the first Japanese woman to earn a doctorate in mathematics, in 1950, and the first to obtain an imperial university professorship in mathematics, in 1967.

Life

Katsurada was born in

Akaigawa, Hokkaido is a village located in Shiribeshi, Hokkaido, Japan. As of October 2020, the village has an estimated population of 1,165. The total area is 280.11 km2. History The name derives from Ainu word "hure-pet", meaning "red river". *1899: Ak ...

on 3 September 1911, a daughter of an elementary school principal. In high school in

Otaru is a Cities of Japan, city and Seaports of Japan, port in Shiribeshi Subprefecture, Hokkaido, Japan, northwest of Sapporo. The city faces Ishikari Bay and the Sea of Japan, and has long served as the main port of the bay. With its many historical ...

, she took special instruction in mathematics from a boys' mathematics instructor. Graduating from high school in 1929, she began auditing classes at the , a predecessor to the

Tokyo University of Science , formerly "Science University of Tokyo" or TUS, informally or simply is a private research university located in Shinjuku, Tokyo, Japan. History Tokyo University of Science was founded in 1881 as The Tokyo Academy of Physics by 21 graduate ...

, in 1931. She began working as an administrative assistant in the

Hokkaido University , or , is a public research university in Sapporo, Hokkaido, Japan. Founded in 1918, it is the fifth-oldest government-authorised university in Japan and one of the former Imperial Universities. The university finds its roots in Sapporo A ...

Department of Mathematics in 1936. In 1938 she began study in mathematics at

Tokyo Woman's Christian University , often abbreviated to TWCU or , is an independent Protestant university in Tokyo, Japan. Founding TWCU was established by Nitobe Inazō (1862–1933), an author, diplomat and educator, who was appointed as the first president in 1918. The firs ...

, withdrawing in 1940 to transfer to Hokkaido University. She graduated from Hokkaido University in 1942, and in the same year became an assistant professor there. In 1950, she completed a doctorate in mathematics at Hokkaido University, under the supervision of Shoji Kawaguchi, becoming the first Japanese woman to earn a doctorate in mathematics, and earning a promotion to associate professor. She remained at Hokkaido University for the remainder of her career, with research visits to

Sapienza University of Rome The Sapienza University of Rome (), formally the Università degli Studi di Roma "La Sapienza", abbreviated simply as Sapienza ('Wisdom'), is a Public university, public research university located in Rome, Italy. It was founded in 1303 and is ...

ETH Zurich ETH Zurich (; ) is a public university in Zurich, Switzerland. Founded in 1854 with the stated mission to educate engineers and scientists, the university focuses primarily on science, technology, engineering, and mathematics. ETH Zurich ran ...

, and the

University of California, Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California), is a Public university, public Land-grant university, land-grant research university in Berkeley, California, United States. Founded in 1868 and named after t ...

. She was promoted to full professor in 1967, the first female professor in mathematics at a former imperial university. She retired in 1975, and died on 10 May 1980.

Research

Katsurada's early research, from the beginning of her studies into the mid-1950s, primarily concerned

line element In geometry, the line element or length element can be informally thought of as a line segment associated with an infinitesimal displacement vector in a metric space. The length of the line element, which may be thought of as a differential arc ...

s; this was the primary interest of her advisor Shoji Kawaguchi, with whom she continued to collaborate on this subject. After visiting

Heinz Hopf Heinz Hopf (19 November 1894 – 3 June 1971) was a German mathematician who worked on the fields of dynamical systems, topology and geometry. Early life and education Hopf was born in Gräbschen, German Empire (now , part of Wrocław, Poland) ...

in 1957–1958, she shifted interests to

submanifold In mathematics, a submanifold of a manifold M is a subset S which itself has the structure of a manifold, and for which the inclusion map S \rightarrow M satisfies certain properties. There are different types of submanifolds depending on exactly ...

s and

hypersurface In geometry, a hypersurface is a generalization of the concepts of hyperplane, plane curve, and surface. A hypersurface is a manifold or an algebraic variety of dimension , which is embedded in an ambient space of dimension , generally a Euclidea ...

s in

Riemannian manifold In differential geometry, a Riemannian manifold is a geometric space on which many geometric notions such as distance, angles, length, volume, and curvature are defined. Euclidean space, the N-sphere, n-sphere, hyperbolic space, and smooth surf ...

s, publishing well-regarded work in this area.

Recognition

Several papers in the 1972 volume of the ''Hokkaido Mathematical Journal'' are dedicated to Katsurada in honor of her 60th birthday. Katsurada was given the Hokkaido Culture Award in 1973.

References

{{DEFAULTSORT:Katsurada, Yoshie 1911 births 1980 deaths Japanese mathematicians Japanese women mathematicians Hokkaido University alumni Academic staff of Hokkaido University Differential geometers Scientists from Hokkaido