Ralph Tambs Lyche

Ralph Tambs-Lyche (6 September 1890–1991) was a Norwegian mathematician.

He was born in the United States to a Norwegian father and an American mother, but moved to Norway at the age of two. He graduated from the Royal Frederick University in 1916, and was hired as a docent in mathematics at the Norwegian Institute of Technology in 1918. He took his doctorate in Strasbourg in 1927 following a two-year fellowship there. In 1937 he was promoted to professor, a position he held until 1950. He was then a professor at the University of Oslo until his retirement in 1961. His fields were mathematical analysis, function theory, algebra and number theory. He penned about 60 mathematical works, and also a few publications in botany; he was a hobby herbarist. He also became widely known for his mathematical textbooks, both for the upper secondary school and another for technical colleges and universities, and was an editorial board member of the journal Nordisk Matematisk Tidsskrift.

He was a member of the Royal Norwegian Society of Sciences and Letters from 1927, and of the Norwegian Academy of Science and Letters from 1946. From 1946 to 1950 he was the secretary-general of the Royal Norwegian Society of Sciences and Letters. He chaired the Student Society in Trondheim in 1920, and later held speeches during political meetings there. He was a member of Clarté, affiliated with Mot Dag. During the martial law in Trondheim in 1942, organized by the occupying Nazi authorities, he was imprisoned at Falstad concentration camp. He avoided execution unlike some others, but remained imprisoned throughout World War II.

Ralph Tambs-Lyche was the father of solidarity activist Guri Tambs-Lyche. His wife Elsa was a pioneer in maternal hygiene work. He died in early 1991, at the age of 100.