Lars Onsager

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Norwegian–American chemist (1903–1976)

Born at Christiania (now Oslo) in Norway, Onsager was educated at the Norwegian Institute of Technology. He moved to America in 1928 and obtained his PhD at Yale in 1935. He spent virtually his whole career at Yale, serving as J. W. Gibbs Professor of Theoretical Chemistry from 1945 until 1972.

Onsager made two important contributions to chemical theory. In 1926 he showed the need to modify the equation established by Peter Debye and Erich Hückel in 1923 which described the behavior of ions in a solution, by taking Brownian motion into consideration.

Onsager's main work, however, was in the foundation of the study of nonequilibrium thermodynamics. Here an attempt is made to apply the normal laws of thermodynamics to systems that are not in equilibrium – where there are temperature, pressure, or potential differences of some kind. For his work in this field Onsager was awarded the Nobel Prize for chemistry in 1968. The study of nonequilibrium thermodynamics was further developed by Ilya Prigogine.

Lars Onsager (1903-1976) made significant contributions to chemistry, including his developments in the Debye-Hückel theory of electrolytic dissociation and his work with non-reversable systems. He received the 1968 Nobel Prize in Chemistry.

Born in Norway, Lars Onsager received his early education there before coming to the United States in 1928 to do graduate work at Yale University. After receiving his Ph.D. in theoretical chemistry he stayed on at Yale and ultimately spent nearly all of his academic career at that institution. Onsager's first important contribution to chemical theory came in 1926 when he showed how improvements could be made in the Debye-Hückel theory of electrolytic dissociation. His later (and probably more significant) work involved non-reversible systems - systems in which differences in pressure, temperature, or some other factor are an important consideration. For his contributions in this field, Onsager received a number of important awards including the Rumford Medal of the American Academy of Arts and Sciences, the Lorentz Medal of the Royal Netherlands Academy of Sciences, and the 1968 Nobel Prize in Chemistry.

Lars Onsager was born in Oslo (then known as Christiania), Norway, on November 27, 1903. His parents were Erling Onsager, a barrister before the Norwegian Supreme Court, and Ingrid Kirkeby Onsager. Onsager's early education was somewhat unorthodox as he was taught by private tutors, by his own mother, and at a somewhat unsatisfactory rural private school. Eventually he entered the Frogner School in Oslo and did so well that he skipped a grade and graduated a year early. Overall, his early schooling provided him with a broad liberal education in philosophy, literature, and the arts. He is said to have become particularly fond of Norwegian epics and continued to read and recite them to friends and family throughout his life.

In 1920, Onsager entered the Norges Tekniski Hoslashgskole in Trondheim where he planned to major in chemical engineering. The fact that he enrolled in a technical high school suggests that he was originally interested in practical rather than theoretical studies. Onsager had not pursued his schooling very long, however, before it became apparent that he wanted to go beyond the everyday applications of science to the theoretical background on which those applications are based. Even as a freshman in high school, he told of making a careful study of the chemical journals, in order to gain background knowledge of chemical theory.

One of the topics that caught his attention concerned the chemistry of solutions. In 1884, Svante Arrhenius had proposed a theory of ionic dissociation that explained a number of observations about the conductivity of solutions and, eventually, a number of other solution phenomena. Over the next half century, chemists worked on refining and extending the Arrhenius theory.

The next great step forward in that search occurred in 1923, when Onsager was still a student at the Tekniski Hoslashgskole. The Dutch chemist Peter Debye and the German chemist Erich Hückel, working at Zurich's Eidgenössische Technische Hochschule, had proposed a revision of the Arrhenius theory that explained some problems not yet resolved - primarily, whether ionic compounds are or are not completely dissociated ("ionized") in solution. After much experimentation, Arrhenius had observed that dissociation was not complete in all instances.

Debye and Hückel realized that ionic compounds, by their very nature, already existed in the ionic state before they ever enter a solution. They explained the apparent incomplete level of dissociation on the basis of the interactions among ions of opposite charges and water molecules in a solution. The Debye-Hückel mathematical formulation almost perfectly explained all the anomalies that remained in the Arrhenius theory.

Almost perfectly, but not quite, as Onsager soon observed. The value of the molar conductivity predicted by the Debye-Hückel theory was significantly different from that obtained from experiments. By 1925, Onsager had discovered the reason for this discrepancy. Debye and Hückel had assumed that most - but not all - of the ions in a solution move about randomly in "Brownian" movement . Onsager simply extended that principle to all of the ions in the solution. With this correction, he was able to write a new mathematical expression that improved upon the Debye-Hückel formulation.

Onsager had the opportunity in 1925 to present his views to Debye in person. Having arrived in Zurich after traveling through Denmark and Germany with one of his professors, Onsager is reported to have marched into Debye's office in Zurich and declared, "Professor Debye, your theory of electrolytes is incorrect." Debye was sufficiently impressed with the young Norwegian to offer him a research post in Zurich, a position that Onsager accepted and held for the next two years.

In 1928, Onsager emigrated to the United States where he became an associate in chemistry at Johns Hopkins University. The appointment proved to be disastrous: he was assigned to teach the introductory chemistry classes, a task for which he was completely unsuited. One of his associates, Robert H. Cole, is quoted in the Biographical Memoirs of Fellows of the Royal Society: "I won't say he was the world's worst lecturer, but he was certainly in contention." As a consequence, Onsager was not asked to return to Johns Hopkins after he had completed his first semester there.

Fortunately, a position was open at Brown University, and Onsager was asked by chemistry department chairman Charles A. Krauss to fill that position. During his 5-year tenure at Brown, Onsager was given a more appropriate teaching assignment, statistical mechanics. His pedagogical techniques apparently did not improve to any great extent, however; he still presented a challenge to students by speaking to the blackboard on topics that were well beyond the comprehension of many in the room.

A far more important feature of the Brown years was the theoretical research that Onsager carried out in the privacy of his own office. In this research, Onsager attempted to generalize his earlier research on the motion of ions in solution when exposed to an electrical field. In order to do so, he went back to some fundamental laws of thermodynamics, including Hermann Helmholtz's "principle of least dissipation." He was eventually able to derive a very general mathematical expression about the behavior of substances in solution, an expression now known as the Law of Reciprocal Relations.

Onsager first published the law in 1929, but continued to work on it for a number of years. In 1931, he announced a more general form of the law that applied to other non-equilibrium situations in which differences in electrical or magnetic force, temperature, pressure, or some other factor exists. The Onsager formulation was so elegant and so general that some scientists now refer to it as the Fourth Law of Thermodynamics.

The Law of Reciprocal Relations was eventually recognized as an enormous advance in theoretical chemistry, earning Onsager the Nobel Prize in 1968. However, its initial announcement provoked almost no response from his colleagues. It is not that they disputed his findings, Onsager said many years later, but just that they totally ignored them. Indeed, Onsager's research had almost no impact on chemists until after World War II had ended, more than a decade after the research was originally published.

The year 1933 was a momentous one for Onsager. It began badly when Brown ended his appointment because of financial pressures brought about by the Great Depression. His situation improved later in the year, however, when he was offered an appointment as Sterling and Gibbs Fellow at Yale. The appointment marked the beginning of an affiliation with Yale that was to continue until 1972.

Prior to assuming his new job at Yale, Onsager spent the summer in Europe. While there, he met the future Mrs. Onsager, Margarethe Arledter, the sister of the Austrian electrochemist H. Falkenhagen. The two apparently fell instantly in love, became engaged a week after meeting, and were married on September 7, 1933. The Onsagers later had three sons, Erling Frederick, Hans Tanberg, and Christian Carl, and one daughter, Inger Marie.

Onsager had no sooner assumed his post at Yale when a small problem arose: the fellowship he had been awarded was for postdoctoral studies, but Onsager had not as yet been granted a Ph.D. He had submitted an outline of his research on reciprocal relations to his alma mater, the Norges Tekniski Hoslashgskole, but the faculty there had decided that, being incomplete, it was not worthy of a doctorate. As a result, Onsager's first task at Yale was to complete a doctoral thesis. For this thesis, he submitted to the chemistry faculty a research paper on an esoteric mathematical topic. Since the thesis was outside the experience of anyone in the chemistry or physics departments, Onsager's degree was nearly awarded by the mathematics department, whose chair understood Onsager's findings quite clearly. Only at the last moment did the chemistry department relent and agree to accept the judgment of its colleagues, awarding Onsager his Ph.D. in 1935.

Onsager continued to teach statistical mechanics at Yale, although with as little success as ever. (Instead of being called "Sadistical Mechanics," as it had been by Brown students, it was now referred to as "Advanced Norwegian" by their Yale counterparts.) As always, it was Onsager's theoretical - and usually independent - research that justified his Yale salary. In his nearly four decades there, he attacked one new problem after another, usually with astounding success. Though his output was by no means prodigious, the quality and thoroughness of his research was impeccable.

During the late 1930s, Onsager worked on another of Debye's ideas, the dipole theory of dielectrics . That theory had, in general, been very successful, but could not explain the special case of liquids with high dielectric constants. By 1936, Onsager had developed a new model of dipoles that could be used to modify Debye's theory and provide accurate predictions for all cases. Onsager was apparently deeply hurt when Debye rejected his paper explaining this model for publication in the Physikalische Zeitschrift, which Debye edited. It would be more than a decade before the great Dutch chemist, then an American citizen, could accept Onsager's modifications of his ideas.

In the 1940s, Onsager turned his attention to the very complex issue of phase transitions in solids. He wanted to find out if the mathematical techniques of statistical mechanics could be used to derive the thermodynamic properties of such events. Although some initial progress had been made in this area, resulting in a theory known as the Ising model, Onsager produced a spectacular breakthrough on the problem. He introduced a "trick or two" (to use his words) that had not yet occurred to (and were probably unknown to) his colleagues - the use of elegant mathematical techniques of elliptical functions and quaternion algebra. His solution to this problem was widely acclaimed.

Though his status as a non-U.S. citizen enabled him to devote his time and effort to his own research during World War II, Onsager was forbidden from contributing his significant talents to the top-secret Manhattan Project, the United State's research toward creating atomic weapons. Onsager and his wife finally did become citizens as the war drew to a close in 1945.

The postwar years saw no diminution of Onsager's energy. He continued his research on low-temperature physics and devised a theoretical explanation for the superfluidity of helium II (liquid helium). The idea, originally proposed in 1949, was arrived at independently two years later by Princeton University's Richard Feynman. Onsager also worked out original theories for the statistical properties of liquid crystals and for the electrical properties of ice. In 1951 he was given a Fulbright scholarship to work at the Cavendish Laboratory in Cambridge; there, he perfected his theory of diamagnetism in metals.

During his last years at Yale, Onsager continued to receive numerous accolades for his newly appreciated discoveries. He was awarded honorary doctorates by such noble universities as Harvard (1954), Brown (1962), Chicago (1968), Cambridge (1970), and Oxford (1971), among others. He was inducted to the National Academy of Sciences in 1947. In addition to his Nobel Prize, Onsager garnered the American Academy of Arts and Sciences' Rumford Medal in 1953 and the Lorentz Medal in 1958, as well as several medals from the American Chemical Society and the President's National Medal of Science. Upon reaching retirement age in 1972, Onsager was offered the title of emeritus professor, but without an office. Disappointed by this apparent slight, Onsager decided instead to accept an appointment as Distinguished University Professor at the University of Miami's Center for Theoretical Studies. At Miami, Onsager found two new subjects to interest him, biophysics and radiation chemistry. In neither field did he have an opportunity to make any significant contributions, however, as he died on October 5, 1976, apparently the victim of a heart attack.

Given his shortcomings as a teacher, Onsager still seems to have been universally admired and liked as a person. Though modest and self-effacing, he possessed a wry sense of humor. In Biographical Memoirs, he is quoted as saying of research, "There's a time to soar like an eagle, and a time to burrow like a worm. It takes a pretty sharp cookie to know when to shed the feathers and … to begin munching the humus." In a memorial some months after Onsager's death, Behram Kursunoglu, the director of the University of Miami's Center for Theoretical Studies, described him as a "very great man of science - with profound humanitarian and scientific qualities."

Further Reading

Biographical Memoirs of Fellows of the Royal Society, Volume 24, Royal Society (London), 1978.

Current Biography 1958, H. W. Wilson, 1958.

Nobel Lectures in Chemistry, 1963-1970, [Amsterdam], 1972.

Lars Onsager
Lars Onsager
Born	November 27, 1903(1903-11-27) Kristiania (Oslo), Norway
Died	October 5, 1976 (aged 72) Coral Gables, Florida, U.S.
Residence	United States
Nationality	Norway, U.S.
Fields	Physical chemist
Institutions	ETH Zürich Johns Hopkins University Brown University Yale University
Alma mater	Norwegian Institute of Technology
Doctoral students	Joseph L. McCauley
Known for	Onsager reciprocal relations, the exact solution to the two-dimensional Ising model and for revealing the physics behind the De Haas–van Alphen effect
Notable awards	Nobel Prize in Chemistry (1968)

Lars Onsager (November 27, 1903 – October 5, 1976) was a Norwegian–American physical chemist and theoretical physicist, winner of the 1968 Nobel Prize in Chemistry. He had the Gibbs Professorship of Theoretical Chemistry at Yale University.

Contents 1 Biography 1.1 Johns Hopkins University 1.2 Brown University 1.3 Yale University 2 After Yale 3 Legacy 4 See also 5 Notes 6 References 7 External links

Biography

Lars Onsager was born in Kristiania (today's Oslo), Norway. His father was a lawyer. After completing secondary school in Oslo, he attended the Norwegian Institute of Technology (NTH) in Trondheim, graduating as a chemical engineer in 1925.

In 1925 he arrived at a correction to the Debye–Hückel theory of electrolytic solutions, to specify Brownian movement of ions in solution, and during 1926 published it. He traveled to Zürich, where Peter Debye was teaching, and confronted Debye, telling him his theory was wrong. He impressed Debye so much that he was invited to become Debye's assistant at the Eidgenössische Technische Hochschule (ETH), where he remained until 1928.

Johns Hopkins University

Eventually in 1928 he went to the United States of America to take a faculty position at the Johns Hopkins University in Baltimore, Maryland. At JHU he had to teach freshman classes in chemistry, and it quickly became apparent that, while he was a genius at developing theories in physical chemistry, he had little talent for teaching. He was dismissed by JHU after one semester.

Brown University

On leaving JHU, he accepted a position (involving the teaching of statistical mechanics to graduate students in chemistry) at Brown University in Providence, Rhode Island, where it became clear that he was no better at teaching advanced students than freshmen, but he made significant contributions to statistical mechanics and thermodynamics. The only graduate student who could really understand his lectures on electrolyte systems, Raymond Fuoss, worked under him and eventually joined him on the Yale chemistry faculty. In 1933, when the Great Depression limited Brown's ability to support a faculty member who was only useful as a researcher and not a teacher, he was let go by Brown, being hired after a trip to Europe by Yale University, where he remained for most of the rest of his life, retiring in 1972.

His research at Brown was concerned mainly with the effects on diffusion of temperature gradients, and produced the Onsager reciprocal relations, a set of equations published in 1929 and, in an expanded form, in 1931, in statistical mechanics whose importance went unrecognized for many years. However, their value became apparent during the decades following World War II, and by 1968 they were considered important enough to gain Onsager that year's Nobel Prize in Chemistry.

In 1933, just before taking up the position at Yale, Onsager traveled to Austria to visit electrochemist Hans Falkenhagen. He met Falkenhagen's sister-in-law, Margrethe Arledter. They were married on September 7, 1933, and had three sons and a daughter.

Yale University

At Yale, an embarrassing situation occurred: he had been hired as a postdoctoral fellow, but it was discovered that he had never received a Ph.D. While he had submitted an outline of his work in reciprocal relations to the Norwegian Institute of Technology, they had decided it was too incomplete to qualify as a doctoral dissertation. He was told that he could submit one of his published papers to the Yale faculty as a dissertation, but insisted on doing a new research project instead. His dissertation, entitled, "Solutions of the Mathieu equation of period 4 pi and certain related functions", was beyond the comprehension of the chemistry and physics faculty, and only when some members of the mathematics department, including the chairman, insisted that the work was good enough that they would grant the doctorate if the chemistry department would not, was he granted a Ph.D. in chemistry in 1935. Even before the dissertation was finished, he was appointed assistant professor in 1934, and promoted to associate professor in 1940. He quickly showed at Yale the same traits he had at JHU and Brown: he produced brilliant theoretical research, but was incapable of giving a lecture at a level that a student (even a graduate student) could comprehend. He was also unable to direct the research of graduate students, except for the occasional outstanding one.

During the late 1930s, Onsager researched the dipole theory of dielectrics, making improvements for another topic that had been studied by Peter Debye. However, when he submitted his paper to a journal that Debye edited in 1936, it was rejected. Debye would not accept Onsager's ideas until after World War II. During the 1940s, Onsager studied the statistical-mechanical theory of phase transitions in solids, deriving a mathematically elegant theory which was enthusiastically received. He obtained the exact solution for the two dimensional Ising model in zero field in 1944.

In 1945, Onsager was naturalized as an American citizen, and the same year he was awarded the title of J. Willard Gibbs Professor of Theoretical Chemistry. This was particularly appropriate because Onsager, like Willard Gibbs, had been involved primarily in the application of mathematics to problems in physics and chemistry and, in a sense, could be considered to be continuing in the same areas Gibbs had pioneered.

In 1947, he was elected to the National Academy of Sciences, and in 1950 he joined the ranks of Alpha Chi Sigma.

After World War II, Onsager researched new topics of interest. He proposed a theoretical explanation of the superfluid properties of liquid helium in 1949; two years later the physicist Richard Feynman independently proposed the same theory. He also worked on the theories of liquid crystals and the electrical properties of ice. While on a Fulbright scholarship to Cambridge University, he worked on the magnetic properties of metals. He developed important ideas on the quantization of magnetic flux in metals. He was awarded the Lorentz Medal in 1958 and the Nobel Prize in Chemistry in 1968.

After Yale

Graves of Onsager and Kirkwood

Onsager retired at age 70 at Yale and became emeritus. He was appointed Distinguished University Professor at the University of Miami (Florida)in 1973 in the Center for Theoretical Studies. He remained active in guiding and inspiring postdoctoral students as his teaching skills, although not his lecturing skills, had improved during the course of his career. He developed interests in semiconductor physics, biophysics and radiation chemistry. However, his death came before he could produce any breakthroughs comparable to those of his earlier years.

He remained in Florida until his death from an aneurysm in Coral Gables, Florida in 1976. Onsager was buried next to John Gamble Kirkwood at New Haven's Grove Street Cemetery. While Kirkwood's tombstone has a long list of awards and positions, including the American Chemical Society Award in Pure Chemistry, the Richards Medal, and the Lewis Award, Onsager's tombstone, in its original form, simply said "Nobel Laureate."^[1] When Onsager's wife Gretel died in 1991 and was buried there, his children added an asterisk after "Nobel Laureate," and "*etc." in the lower right corner of the stone.

Legacy

The Norwegian Institute of Technology established the Lars Onsager Lecture and The Lars Onsager Professorship in 1993 to award outstanding scientists in the scientific fields of Lars Onsager; Chemistry, Physics and Mathematics.^[2] In 1997 his sons and daughter donated his scientific works and professional belongings to NTNU (before 1996 NTH) in Trondheim, Norway as his Alma Mater. These are now organized as The Lars Onsager Archive at the Gunnerus Library in Trondheim.

See also

• Onsager reciprocal relations
• De Haas–van Alphen effect

Notes

1. ^ Grove Street Cemetery
2. ^ The Lars Onsager Lecture and The Lars Onsager Professorship Norwegian Institute of Technology entry

References

• The Collected Works of Lars Onsager (with Commentary) World Scientific Series in 20th Century Physics - Vol. 17 Editors: Per Chr Hemmer, Helge Holden and Signe Kjelstrup Ratkje (World Scientific, Singapore 1996) ISBN 981-02-2563-6.

• Constitutions of matter : mathematically modelling the most everyday of physical phenomena by Martin H. Krieger, University of Chicago Press, 1996. ISBN 0-226-45304-9 Contains a detailed pedagogical discussion of Onsager's solution of the phase transition of the 2-D Ising model.

• H. Christopher Longuet-Higgins; Michael E. Fisher (1991). "Lars Onsager. 27 November 1903-5 October 1976". Biographical Memoirs (National Academy of Sciences) 60: 182–233. http://books.nap.edu/openbook.php?record_id=6061&page=182. 

External links

• Onsager's Nobel Foundation biography
• Onsager's Nobel Lecture The Motion of Ions: Principles and Concepts
• The Lars Onsager Archive
• Lars Onsager profile, NNDB.
• The Lars Onsager Lecture and The Lars Onsager Professorship.
• Lars Onsager at the Mathematics Genealogy Project

v • d • e Nobel Laureates in Chemistry Edwin McMillan / Glenn T. Seaborg (1951) · Archer Martin / Richard Synge (1952) · Hermann Staudinger (1953) · Linus Pauling (1954) · Vincent du Vigneaud (1955) · Cyril Hinshelwood / Nikolay Semyonov (1956) · Alexander Todd (1957) · Frederick Sanger (1958) · Jaroslav Heyrovský (1959) · Willard Libby (1960) · Melvin Calvin (1961) · Max Perutz / John Kendrew (1962) · Karl Ziegler / Giulio Natta (1963) · Dorothy Hodgkin (1964) · Robert Woodward (1965) · Robert S. Mulliken (1966) · Manfred Eigen / Ronald Norrish / George Porter (1967) · Lars Onsager (1968) · Derek Barton / Odd Hassel (1969) · Luis Federico Leloir (1970) · Gerhard Herzberg (1971) · Christian B. Anfinsen / Stanford Moore / William Stein (1972) · E.O.Fischer / Geoffrey Wilkinson (1973) · Paul Flory (1974) · John Cornforth / Vladimir Prelog (1975) Complete roster · 1901–1925 · 1926–1950 · 1951–1975 · 1976–2000 · 2001–present

Persondata
NAME	Onsager, Lars
ALTERNATIVE NAMES
SHORT DESCRIPTION	Physical chemist
DATE OF BIRTH	November 27, 1903
PLACE OF BIRTH	Christiania, (Oslo), Norway
DATE OF DEATH	October 5, 1976
PLACE OF DEATH	Coral Gables, Florida, U.S.

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