The Lars Onsager

Online archive

Biographical note

Norwegian University of Science and Technology
NTNU Library

Lars Onsager, Norwegian-American chemist and physicist, was born in Oslo on November 27th 1903 to Erling Onsager, a barrister, and Ingrid, née Kirkeby. In 1933 Lars Onsager married the Austrian-born Margarethe Arledter. They had four children, Erling Fredrick, Inger Marie, Hans Tanberg and Christian Carl.

Onsager received the Ch.E. degree from the Norwegian Institute of Technology (Norges Tekniske Höiskole) in 1925. He was Peter Debye's assistant in Zürich until 1928, when he went to Johns Hopkins University. He was then instructor in chemistry at Brown University from 1928 to 1933. He became a Stirling Fellow at Yale University in 1933, and received a Ph.D. from Yale in 1935. He was appointed assistant professor there in 1934, associate professor in 1940, and J. Willard Gibbs Professor of Theoretical Chemistry in 1945. From 1972 to 1976, he was Distinguished University Professor at the University of Miami, Coral Gables. He died on October 5th 1976.

In 1968 Onsager was awarded the Nobel Prize in Chemistry, for his fundamental contributions to irreversible thermodynamics. The so-called Onsager reciprocal relations that he derived have been of tremendous importance in a wide range of applications. In addition to the theory of irreversible processes, Onsager did pioneer work in several other fields of chemistry and physics. The first articles he published concerned the thermodynamics and kinetics of electrolytes, topics to which he made important contributions throughout his scientific career.

In 1944 he baffled the scientific world with the exact solution of the two-dimensional Ising model, a model of a ferromagnet. The solution was a virtuosic mathematical feat. It was also

important from a physical point of view, and started a development that led to a deeper understanding of phase transitions and critical points. From about 1940 Onsager was very interested in low-temperature physics. He suggested the quantization of vortices in liquid helium, and showed in 1952 how information about the distribution of electrons could be extracted from the de Haas-van Alphen effect.

In addition to the Nobel Prize, Onsager received many honours, medals and prizes, including honorary degrees from Harvard University, Norges Tekniske Høgskole, Brown University, Rensselaer Polytechnic Institute, Rheinisch-Westfälische Technische Hochschule, University of Chicago, Ohio State University, University of Cambridge and University of Oxford.

General reference: The Collected Works of Lars Onsager (with commentary). Eds. P.C. Hemmer, H. Holden and S. Kjelstrup Ratkje (World Scientific, Singapore, 1996).

Onsager's desk was moved from his home in the U.S. to Trondheim
and is now placed at Lerkendal gård.

Text written by Monica Aase, Norwegian University of Science and Technology NTNU Library, 1999.