Background
He was born in Tromøy as a son of Alv Kristiansen and Hilda Møller.
He was born in Tromøy as a son of Alv Kristiansen and Hilda Møller.
He became a student in 1951 and graduated from the Norwegian Institute of Technology in 1956.
He took the doctorate already in 1959, and was a research fellow at the University of Copenhagen from 1959 and the Rockefeller University from 1961. He led a project in Oslo between 1963 and 1965, was appointed as docent at the Norwegian Institute of Technology in 1969 and promoted to professor in theoretical physics in 1969. He was vice president of the International Union of Pure and Applied Physics from 1984 to 1990.
He has also contributed to the use of Norwegian language in university physics education, by writing introductory text books in both thermal physics and quantum mechanics that are used at Norges teknisk-naturvitenskapelige universitet and elsewhere.
Norwegian Academy of Science and Letters. Norwegian Academy of Technological Sciences]
He was a member of the Norwegian Academy of Science and Letters from 1966 and the Norwegian Academy of Technological Sciences from 1967.