John Hasbrouck Van Vleck

American physicist (1899–1980)

Van Vleck was born at Middletown, Connecticut, and educated at the University of Wisconsin, where he graduated in 1920. Moving to Harvard University he gained his master's degree (1921) and his doctorate (1922) and stayed for a further year as an instructor. From Harvard he went to the University of Minnesota, where he became a full professor in 1927, returned to Wisconsin in 1928, and then went back to Harvard in 1934.

Van Vleck is regarded as the founder of the modern quantum mechanical theory of magnetism. His earliest papers were on the old quantum theory, but with the advent of wave mechanics pioneered by Paul Dirac he began to look at the implications for magnetism in particular. In the field of paramagnetism he introduced the concept of temperature-independent susceptibility, now known as Van Vleck paramagnetism. He also made calculations of molecular structure that shed new light on chemical bonding and he developed ways of describing the behavior of an atom or an ion in a crystal. Another important contribution of Van Vleck was to point out the importance of electron correlation – the interaction between the motion of electrons – for the appearance of local magnetic moments in metals.

During World War II Van Vleck worked on radar, showing that at about 1.25-centimeter wavelength water molecules in the atmosphere would lead to troublesome absorption and that at 0.5-centimeter wavelength there would be a similar absorption by oxygen molecules. This was to have important consequences not just for military (and civil) radar systems but later for the new science of radioastronomy.

In 1977, together with Nevill Mott and Philip Anderson, he shared the Nobel Prize for physics for “fundamental theoretical investigations of the electronic structure of magnetic and disordered systems.” (Anderson was once a student of Van Vleck's at Harvard.) Van Vleck's work on electron correlation was mentioned specifically for the central role it played in the later development of the laser.

American physicist John Hasbrouck Van Vleck (1899-1980) won the 1977 Nobel Prize for work that laid the foundation for the quantum theory of paramagnetism. Van Vleck is considered the founder of modern theoretical physics, and enjoyed a long career as both researcher and mentor. According toJohn Ellement in the "Boston Globe",the Nobel laureate once explained his field of research as a way to "get at what is the truth of things. The more we know about the universe, the better off we are."

Born on March 13, 1899, in Middletown, Connecticut, Van Vleck hailed from an esteemed family with origins that dated back to some of the first European families to settle in New Jersey. Intellectual achievements were already commonplace in his family by the time he arrived: his grandfather was a professor of astronomy at Wesleyan College in Middletown, Connecticut, and the college's observatory is named in his honor. Van Vleck's father, Edward Burr Van Vleck, was professor of mathematics, also at Wesleyan. It was a stimulating environment for a boy, but Van Vleck claimed he grew up an extremely shy child. Fascinated by railroads, he pored over train time tables for hours on end in order to commit them to memory. Later in his life, he usually traveled without referring to a printed train schedule.

The Van Vleck family relocated to Madison, Wisconsin when Edward Van Vleck was hired by the University of Wisconsin. Summers were sometimes spent in Europe on lengthy family vacations, but back in Madison Van Vleck attended public schools. He then entered the University of Wisconsin, and majored in physics. After graduating in 1920, he was determined to forge his own path in life. Because both his father and grandfather had undertaken active and prominent careers in academia, Van Vleck himself "vowed as a child that I would not be a college professor," as he later wrote in an autobiography posted on the Nobel Prize Website. "But after a semester of graduate work at Harvard, I outgrew my childish prejudices, and realized that the life work for which I was best qualified was that of a physicist, not of the experimental variety, but in an academic environment."

Delved into Theoretical and Quantum Physics

Van Vleck earned his doctorate in physics from Harvard University, and while there he turned toward theoretical physics, which was a new field at the time. In fact, his 1922 doctoral thesis is thought to have been the first American paper based on a purely theoretical subject, in his case the ionization energy of a particular model of the helium atom. Theoretical physics differs from standard physics in that it seeks to predict outcomes by using a model of reality, only part of which may be observable or proven by scientific experiment. Van Vleck's work showed such early promise that job offers came easily: his first postgraduate post came as an instructor in physics at Harvard, and a year later, in 1923, he was hired by the University of Minnesota.

Van Vleck would spend the next five years in Minnesota, and his relatively light teaching load allowed him ample time to devote to research. He began investigating the application of quantum mechanical theory to a variety of physical phenomena, and wrote his first book, Quantum Principles and Line Spectra, in 1926. The work sold unexpectedly well for its subject matter, though its audience was most likely a purely academic one. Quantum science was also a new and exciting field at the time, which certainly accounts for some of the book's appeal.

In 1927 Van Vleck made a breakthrough discovery involving the general theory of magnetic and electric susceptibilities in gases. He also made his first forays into the field that would mark his name in the annals of science: the quantum explanation of magnetic effects. His 1932 book, The Theory of Electric and Magnetic Susceptibilities, featured new ideas regarding the crystal field theory. His research efforts sought to describe paramagnetic salts, especially salts that contained rare-earth ions. It was for this work that Van Vleck earned the 1977 Nobel Prize, as well as the moniker the "father of modern magnetism."

Hired at Harvard

In 1928 Van Vleck returned to his first alma mater, the University of Wisconsin, to become a professor of physics. He rejoined the staff at Harvard University six years later and spent the remainder of his career there. During World War II, he served on a government-appointed committee of scientists charged with evaluating the feasibility of building an atomic bomb; their recommendations spurred the creation of the Manhattan Project, the joint effort that helped bring to fruition the world's first nuclear weapon in 1945. Later into the war Van Vleck became involved in radar work at the Radio Research Laboratory of Cambridge, Massachusetts.

Only later in his career did the work Van Vleck had carried out on crystal field theory, ferromagnetics, and magnetic resonance find practical applications. Some of these include lasers, transistors, and even the copper spirals used in certain birth-control devices. When he was awarded the 1977 Nobel Prize for, in the words of the Nobel committee, his "fundamental theoretical investigations of the electronic structure of magnetic and disordered systems," it was nearly 50 years after he had first launched his research projects. He shared his award with Philip W. Anderson, who had also once been his student, and Sir Nevill Mott. Van Vleck was pleased by the honor, despite the passage of years. "So often the prizes go to younger men," Ellement quoted him as saying in the Boston Globe. "Anybody couldn't help feeling that it is a culmination when you're 78 years old."

In the late 1940s, Van Vleck served as chair of Harvard's physics department, and in the following decade helped create the interdisciplinary Division of Engineering and Applied Physics; he also served as that division's first dean. In 1951 he became the Hollis Professor of Mathematical and Natural Philosophy, the oldest endowed science chair in North America, which he held until his retirement in 1969. He died in Cambridge, Massachusetts, on October 27, 1980, survived by his wife Abigail Pearson Van Vleck, whom he had wed in June of 1927. For much of his life, his friends and colleagues knew him simply as "Van," and though his childhood shyness had endured, he had been known for generously sharing credit on his research projects. As a writer noted in the London Times in announcing his death, Van Vleck "had a warm, outgoing and unassuming personality, always eager to help, be it in personal or professional matters, always generous in his praise of the achievements of his students and colleagues and, relying on his vast fund of knowledge, ever ready to help in solving knotty scientific problems."

Books

Dictionary of American Biography, Supplement 10: 1976-1980, Charles Scribner's Sons, 1995.

World of Physics, edited by Kimberly A. McGrath, Gale, 2001.

Periodicals

Boston Globe, October 28, 1980.

Times (London, England), November 1, 1980.

Online

"John H. Van Vleck," Nobel Prize Website,http://nobelprize.org/physics/laureates/1977/vleck-autobio.html (December 19, 2004).

This article is missing citations or needs footnotes. Please help add inline citations to guard against copyright violations and factual inaccuracies. (March 2008)

John Hasbrouck Van Vleck
Born	March 13, 1899 Middletown, Connecticut
Died	October 27, 1980 Cambridge, Massachusetts
Nationality	United States
Fields	Physics
Institutions	University of Minnesota University of Wisconsin–Madison Harvard University University of Oxford Balliol College
Alma mater	Harvard
Doctoral advisor	Edwin C. Kemble
Doctoral students	Robert Serber Edward Mills Purcell Philip Anderson
Notable awards	Nobel Prize in Physics (1977)

John Hasbrouck Van Vleck (March 13, 1899 – October 27, 1980) was an American physicist and mathematician, co-awarded the 1977 Nobel Prize in Physics, for his contributions to the understanding of the behavior of electrons in magnetic solids.

Contents 1 Life and work 2 Writing 3 Japanese art collector 4 Notes 5 External links

Life and work

Born in Middletown, Connecticut the son of mathematician Edward Burr Van Vleck and grandson of astronomer John Monroe Van Vleck, he grew up in Madison, Wisconsin, received A.B. degree from the University of Wisconsin–Madison in 1920. Then he went to Harvard for graduate studies and got Ph.D degree in 1922. He joined the University of Minnesota as an assistant professor in 1923, then moved to the University of Wisconsin–Madison before settling at Harvard. He also earned Honorary D. Sc., or D. Honoris Causa, degree from Wesleyan University in 1936. ^[1]

J. H. van Vleck established the fundamentals of the quantum mechanical theory of magnetism and the crystal field theory (chemical bonding in metal complexes). He is regarded as the Father of Modern Magnetism. ^{[2] [3] [4]}

During World War II, J. H. van Vleck worked on radar at the MIT Radiation Lab. He was half time at the Radiation Lab and half time on the staff at Harvard. He showed that at about 1.25-centimeter wavelength water molecules in the atmosphere would lead to troublesome absorption and that at 0.5-centimeter wavelength there would be a similar absorption by oxygen molecules. ^{[5] [6] [7] [8]} This was to have important consequences not just for military (and civil) radar systems but later for the new science of radioastronomy.

J. H. van Vleck participated in the Manhattan Project. In June 1942, J. Robert Oppenheimer held a summer study for confirming the concept and feasibility of nuclear weapon at the University of California, Berkeley. Eight theoretical scientists, including J. H. van Vleck, attended it. From July to September, the theoretical study group examined and developed the principles of atomic bomb design. ^{[9] [10] [11]} J. H. van Vleck's theoretical work led to establish the Los Alamos Nuclear Weapons Laboratory. He also served on the Los Alamos Review committee in 1943. The committee, established by General Leslie Groves, also consisted of W.K. Lewis of MIT, Chairman; E.L. Rose, of Jones & Lamson; E.B. Wilson of Harvard; and Richard C. Tolman, Vice Chairman of NDRC. The committee's important contribution (originating with Rose) was a reduction in the size of the firing gun for the Little Boy and Fat Man bomb. This concept eliminated additional design-weight and sped up production of the bomb for its eventual release over Hiroshima and Nagasaki, respectively. ^{[12] [13]}

In the year 1961-62 he was George Eastman Visiting Professor at University of Oxford^[14] and Professorship of Balliol College^[15]. He was awarded the National Medal of Science in 1966 ^[16] and the Lorentz Medal in 1974.^[17] For his contributions to the understanding of the behavior of electrons in magnetic solids, van Vleck was awarded the Nobel Prize in Physics 1977, along with Philip W. Anderson and Sir Nevill Mott.^[18] Van Vleck transformations and Van Vleck paramagnetism^[19] are also named after him.

Died in Cambridge, Massachusetts, aged 81. ^[20]

Writing

• The Absorption of Radiation by Multiply Periodic Orbits, and its Relation to the Correspondence Principle and the Rayleigh-Jeans Law. Part I. Some Extensions of the Correspondence Principle, Physical Review, vol. 24, Issue 4, pp. 330-346 (1924)
• The Absorption of Radiation by Multiply Periodic Orbits, and its Relation to the Correspondence Principle and the Rayleigh-Jeans Law. Part II. Calculation of Absorption by Multiply Periodic Orbits, Physical Review, vol. 24, Issue 4, pp. 347-365 (1924)
• Quantum Principles and Line Spectra, (Bulletin of the National Research Council; v. 10, pt 4, no. 54, 1926)
• The Theory Of Electric And Magnetic Susceptibilities (Clarendon Press, Oxford, 1932).
• Quantum Mechanics, The Key to Understanding Magnetism, Nobel Lecture, December 8, 1977

Japanese art collector

J. H. van Vleck and his wife Abigail were also important art collectors, particularly in the medium of Japanese woodblock prints (principally Ukiyo-e), known as Van Vleck Collection. It was inherited from their father Edward Burr Van Vleck. They donated it to the Chazen Museum of Art in Madison, Wisconsin in 1980s. ^[21]

Notes

1. ^ Autobiography, John H. van Vleck, The Nobel Prize in Physics 1977
2. ^ John H. van Vleck, International Academy of Quantum Molecular Science
3. ^ On the verge of Umdeutung in Minnesota: Van Vleck and the correspondence principle. Part One., Anthony Duncan, Michel Janssen; Elsevier Science, 8 May 2007
4. ^ On the verge of Umdeutung in Minnesota: Van Vleck and the correspondence principle. Part Two., Anthony Duncan, Michel Janssen; Elsevier Science, 8 May 2007
5. ^ Norman F. Ramsey Oral History (1991), NORMAN F. RAMSEY: An Interview Conducted by John Bryant, IEEE History Center, 20 June 1991
6. ^ Oral History Transcript, Interview with John H. Van Vleck by Katherine Sopka at Lyman Laboratory of Physics, 28 January 1977
7. ^ A radar history of World War II, By Louis Brown, Page 442 and Page 521
8. ^ On the Shape of Collision-Broadened Lines, J. H. Van Vleck and V. F. Weisskopf; Reviews of Modern Physics, Volume 17, Number 2 and 3, April-July, 1945
9. ^ New Weapons Laboratory Gives Birth to the "Gadget", 50th Anniversary Article, Los Alamos National Laboratory
10. ^ Berkeley Summer Study Group, The Atomic Heritage Foundation
11. ^ Atomic History Timeline 1900- 1942 , The Atomic Heritage Foundation
12. ^ Oversight Committee Formed as Lab Begins Research, 50th Anniversary Article, Los Alamos National Laboratory
13. ^ Now It Can Be Told: Leslie R. Groves, Lieutenant General, U.S. Army, Retired; Harper, 1962, pp. 162-63.
14. ^ Nobel Laureates, University of Oxford
15. ^ Inspiring minds: the Eastman Professors, Floreat Domus, Balliol College News, Issue 12, June 2006
16. ^ The President's National Medal of Science: Recipient Details, National Science Foundation
17. ^ The Lorents medal
18. ^ The Nobel Prize in Physics 1977
19. ^ Van Vleck paramagnetism, Answers.com
20. ^ John Van Vleck, Nobel Laureate Known for Work on Magnetism; Earned Three Degree, The New York Times, October 28, 1980, Tuesday Page A32
21. ^ E. B. Van Vleck Collection, Chazen Museum of Art

External links

Wikiquote has a collection of quotations related to: John Hasbrouck Van Vleck

• The Theory Of Electric And Magnetic Susceptibilities [1]
• John Hasbrouck van Vleck
• NNDB
• Duncan, Anthony and Janssen, Michel. "On the verge of Undeutung in Minnesota: Van Vleck and the correspondence principle. Part one," Archive for History of Exact Sciences 2007, 61:6, pages 553-624. [2]
• Chazen Museum of Art
• Oral history interview transcript with John Hasbrouck Van Vleck 14 October 1963, American Institute of Physics, Niels Bohr Library & Archives
• Oral history interview transcript with John Hasbrouck Van Vleck 28 February 1966, American Institute of Physics, Niels Bohr Library & Archives
• Oral history interview transcript with John Hasbrouck Van Vleck 28 January 1977, American Institute of Physics, Niels Bohr Library & Archives

v • d • e Nobel Laureates in Physics Burton Richter / Samuel C. C. Ting (1976) · Philip Anderson / Nevill Mott / John van Vleck (1977) · Pyotr Kapitsa / Arno Penzias / Robert Wilson (1978) · Sheldon Glashow / Abdus Salam / Steven Weinberg (1979) · James Cronin / Val Fitch (1980) · Nicolaas Bloembergen / Arthur Schawlow / Kai Siegbahn (1981) · Kenneth G. Wilson (1982) · Subrahmanyan Chandrasekhar / William Fowler (1983) · Carlo Rubbia / Simon van der Meer (1984) · Klaus von Klitzing (1985) · Ernst Ruska / Gerd Binnig / Heinrich Rohrer (1986) · Johannes Bednorz / Karl Müller (1987) · Leon M. Lederman / Melvin Schwartz / Jack Steinberger (1988) · Norman Ramsey / Hans Dehmelt / Wolfgang Paul (1989) · Jerome Friedman / Henry Kendall / Richard E. Taylor (1990) · Pierre de Gennes (1991) · Georges Charpak (1992) · Russell Hulse / Joseph Taylor (1993) · Bertram Brockhouse / Clifford Shull (1994) · Martin Perl / Frederick Reines (1995) · D. Lee / Douglas D. Osheroff / Robert Richardson (1996) · Steven Chu / Claude Cohen-Tannoudji / William Phillips (1997) · Robert B. Laughlin / Horst Störmer / Daniel C. Tsui (1998) · Gerardus 't Hooft / Martinus J. G. Veltman (1999) · Zhores Alferov / Herbert Kroemer / Jack Kilby (2000) Complete roster | (1901–1925) | (1926–1950) | (1951–1975) | (1976–2000) | (2001–present)

v • d • e Presidents of the American Physical Society 1899-1925 Henry Augustus Rowland (1899) · Albert Abraham Michelson (1901) · Arthur Gordon Webster (1903) · C. Barus (1905) · E. Nichols (1907) · H. Crew (1909) · W. Magie (1911) · B. Peirce (1913) · E. Merritt (1914) · Robert Andrews Millikan (1916) · H. Bumstead (1918) · J. Ames (1919) · Theodore Lyman (1921) · Thomas Corwin Mendenhall (1923) · Dayton Miller (1925) 1926-1950 Karl Taylor Compton (1927) · H. Gale (1929) · William Francis Gray Swann (1931) · P. Foote (1933) · Arthur Compton (1934) · Robert W. Wood (1935) · F. Richtmyer (1936) · H. Randall (1937) · L. Briggs (1938) · J. Tate (1939) · John Zeleny (1940) · George Braxton Pegram (1941) · G. Stewart (1941) · Percy Williams Bridgman (1942) · A. Hull (1943) · Arthur Jeffrey Dempster (1944) · Harvey Fletcher (1945) · Edward Condon (1946) · Lee Alvin DuBridge (1947) · J. Robert Oppenheimer (1948) · Francis Wheeler Loomis (1949) · Isidor Isaac Rabi (1950) 1951-1975 Charles Christian Lauritsen (1951) · John Hasbrouck Van Vleck (1952) · Enrico Fermi (1953) · H. Bethe (1954) · Raymond Thayer Birge (1955) · E. Wigner (1956) · Henry DeWolf Smyth (1957) · J. Beams (1958) · George Eugene Uhlenbeck (1959) · V. Weisskopf (1960) · Frederick Seitz (1961) · William Vermillion Houston (1962) · J. Williams (1963) · R. Bacher (1964) · Felix Bloch (1965) · John Archibald Wheeler (1966) · Charles Hard Townes (1967) · James M. Bardeen (1968) · Luis Walter Alvarez (1969) · Edward Mills Purcell (1970) · R. Serber (1971) · Philip M. Morse (1972) · J. Mayer (1973) · Wolfgang K. H. Panofsky (1974) · Chien-Shiung Wu (1975) 1976-2000 W. Fowler (1976) · George Pake (1977) · N. Ramsey (1978) · Lewis M. Branscomb (1979) · Herman Feshbach (1980) · Arthur Leonard Schawlow (1981) · Maurice Goldhaber (1982) · Robert Marshak (1983) · Mildred Dresselhaus (1984) · Robert R. Wilson (1985) · Sidney Drell (1986) · Val Logsdon Fitch (1987) · J. Krumhansl (1989) · Eugen Merzbacher (1990) · Nicolaas Bloembergen (1991) · E. Henley (1992) · Donald N. Langenberg (1993) · B. Richter (1994) · C. Patel (1995) · J. Schrieffer (1996) · D. Bromley (1997) · A. Sessler (1998) · J. Friedman (1999) · J. Langer (2000) 2001-present G. Trilling (2001) · W. Brinkman (2002) · M. Sarachik (2003) · H. Quinn (2004) · M. Cohen (2005) · J. Hopfield (2006) · L. Kadanoff (2007) · A. Bienenstock (2008) · C. Murray (2009)

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)