He 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,[2] then a visiting professor at the University of Colorado, Boulder from 1961 to 1962.[1] His fields were mathematical analysis, function theory, algebra and number theory.[3] 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 (Matematikk for den høgre skolen) and another for technical colleges and universities (Lærebok i matematisk analyse). He was an editorial board member of the journal Nordisk Matematisk Tidsskrift from 1954 to 1960.[1]
Ralph Tambs Lyche was the father of solidarity activist Guri Tambs Lyche. His wife Elsa was a pioneer in maternal hygiene work.[4] He died in January 1991, at the age of 100.[1]