Murray Gell-Mann

Murray Gell-Mann

Murray Gell-Mann lecturing at TED in 2007
Born September 15, 1929 (1929-09-15) (age 81)
Manhattan, New York City, U.S.
Residence United States
Nationality American
Fields Physics
Institutions Santa Fe Institute
California Institute of Technology
University of New Mexico
Alma mater Yale University, MIT
Doctoral advisor Victor Weisskopf
Doctoral students

Kenneth G. Wilson
Sidney Coleman


Rod Crewther
James Hartle
Christopher T. Hill
H. Jay Melosh
Barton Zwiebach
Kenneth Young
Todd Brun[1]
Known for Elementary particles
Notable awards Nobel Prize in Physics (1969)

Murray Gell-Mann (born September 15, 1929, pronounced /ˈmʌriː ˈɡɛl ˈmæn/) is an American physicist who received the 1969 Nobel Prize in physics for his work on the theory of elementary particles.

He formulated the quark model of hadronic resonances, and identified the SU(3) flavor symmetry of the light quarks, extending isospin to include strangeness, which he also discovered. He discovered the V-A theory of chiral neutrinos in collaboration with Richard Feynman. He created current algebra in the 1960s as a way of extracting predictions from quark models when the fundamental theory was still murky, which led to model-independent sum rules confirmed by experiment.

Gell-Mann, along with Maurice Levy, discovered the sigma model of pions, which describes low energy pion interactions. Modifying the integer-charged quark model of Han and Nambu, Fritzsch and Gell-Mann were the first to write down the modern accepted theory of quantum chromodynamics although they did not anticipate asymptotic freedom.

Gell-Mann is responsible for the see-saw theory of neutrino masses, that produces masses at the inverse-GUT scale in any theory with a right-handed neutrino, like the SO(10) model.

He is also known to have played a large role in keeping string theory alive through the 1970s, supporting that line of research at a time when it was unpopular.

Contents

Biography

Born in lower Manhattan into a family of Jewish immigrants from Czernowitz, Austro-Hungarian Empire[2], Gell-Mann quickly revealed himself as a child prodigy. Propelled by an intense boyhood curiosity and love for nature, he entered Yale at fifteen after graduating valedictorian from the Columbia Grammar and Preparatory School.

Gell-Mann's work in the 1950s involved recently discovered cosmic ray particles that came to be called kaons and hyperons. Classifying these particles led him to propose a new quantum number called strangeness. Another of Gell-Mann's ideas is the Gell-Mann–Nishijima formula, which was, initially, a formula based on empirical results, but was later explained by the quark model. Gell-Mann and Abraham Pais were involved in explaining many puzzling aspects of the physics of these particles.

In 1961, this led him (and Kazuhiko Nishijima) to introduce a classification of elementary particles called hadrons (also independently proposed by Yuval Ne'eman six months earlier, although Gell-Mann alone got the Nobel Prize). This scheme is now explained by the quark model. Gell-Mann's own name for the classification scheme was the eightfold way, because of the octets of particles in the classification. The term is a reference to the eightfold way of Buddhism — a choice which is reflective of Gell-Mann's eclectic interests.

Gell-Mann, and, independently, George Zweig, went on, in 1964, to postulate the existence of quarks, the particles from which the hadrons are composed. The name was coined by Gell-Mann and is a reference to the novel Finnegans Wake, by James Joyce ("Three quarks for Muster Mark!" - book 2, episode 4). Zweig had referred to the particles as "aces"[3] but Gell-Mann's name caught on.

Quarks were soon accepted as the underlying elementary objects in the study of the structure of hadrons. In 1972 he introduced with Harald Fritzsch the quantum number 'color' and later, in a joint paper with Heinrich Leutwyler, the full theory of quantum chromodynamics (QCD) was released as the gauge theory of strong interactions (cf. references).

The quark model is part of QCD, and has been robust enough to survive the discovery of other flavours of quarks.

Gell-Mann and Richard Feynman, working together, and a rival group of George Sudarshan and Robert Marshak, were the first to discover the vector structure of the weak interaction in physics. This work followed the discovery of parity violation by Chien-Shiung Wu, as suggested by Chen Ning Yang and T. D. Lee.

In the 1990s his interest turned to the emerging study of complexity, where he was closely associated with the Santa Fe Institute. He wrote a popular science book about these matters, The Quark and the Jaguar: Adventures in the Simple and the Complex. The title of the book is taken from a line of an Arthur Sze poem: "The world of the quark has everything to do with a jaguar circling in the night."

George Johnson wrote a biography of Gell-Mann, which is entitled Strange Beauty: Murray Gell-Mann and the Revolution in 20th-Century Physics.

Gell-Mann is also a collector of East Asian antiquities and a keen linguist.

In the 2008 U.S. presidential election, Gell-Mann endorsed Barack Obama.[4]

Timeline

Gell-Mann earned a bachelor's degree in physics from Yale University in 1948, and a PhD in physics from MIT in 1951. He was a postdoctoral research associate in 1951, and a visiting research professor at University of Illinois at Urbana-Champaign from 1952 to 1953. After serving as Visiting Associate Professor at Columbia University in 1954-55, he became a professor at the University of Chicago before moving to the Caltech, where he taught from 1955 until 1993. He was awarded a Nobel Prize in physics in 1969 for his discovery of a system for classifying subatomic particles.

He is currently the Robert Andrews Millikan Professor of Theoretical Physics Emeritus at Caltech as well as a University Professor in the Physics and Astronomy Department of the University of New Mexico in Albuquerque, New Mexico. He is a member of the editorial board of the Encyclopædia Britannica. In 1984 Gell-Mann co-founded the Santa Fe Institute — a non-profit research institute in Santa Fe, New Mexico — to study complex systems and disseminate the notion of a separate interdisciplinary study of complexity theory. There he met and befriended Pulitzer Prize-winning novelist Cormac McCarthy.[5]

Personal life

Gell-Mann married Marcia Southwick in 1992, after the death of his first wife, J. Margaret Dow (d. 1981), whom he married in 1955. His children are Elizabeth Sarah Gell-Mann (b. 1956) and Nicholas Webster Gell-Mann (b. 1963); and he has a stepson, Nicholas Southwick Levis (b. 1978).

Awards

Awards and honors

Notes

References and further reading

See also

External links