Lochlainn O'Raifeartaigh
Encyclopedia
Lochlainn O’Raifeartaigh (11 March 1933 – 18 November 2000) was an Irish
physicist
of worldwide repute in the field of theoretical particle physics. He is best known for the O'Raifeartaigh Theorem, an important result in unification theory, and the O'Raifeartaigh Model of supersymmetry breaking
.
O'Raifeartaigh was born in Dublin in 1933, and most of his scientific career was centred around that city, where he obtained his first degrees at University College Dublin
(BA in 1953 and MSc in Mathematical Physics in 1956), and spent from 1968 until his death as Senior Professor at the Dublin Institute for Advanced Studies
. He obtained his doctorate from the University of Zurich
in 1960, under Walter Heitler
. He also visited many institutions, notably Madras, IHES Bures, and the Institute for Advanced Study
in Princeton, New Jersey
, but it was during an extended stay at Syracuse University
(1964-8) that he made the discovery that established his reputation. This result, which became known as O'Raifeartaigh's no-go theorem, showed that it was impossible to combine internal and relativistic symmetries other than in a trivial fashion, thus ending a widespread quest by the particle physics community to achieve this fusion. The O'Raifeartaigh theorem was later generalized to a more famous result known as the Coleman-Mandula theorem.
O'Raifeartaigh's prolific career in theoretical physics was manifested by many fundamental contributions to the application of symmetries in particle physics
. In the 1970s he showed that the new supersymmetries could provide a mechanism (O'Raifeartaigh's mechanism) for circumventing his no-go theorem which had assumed only classical Lie group
symmetries. In the 1980s he applied non-Abelian gauge theory to the analysis of magnetic monopole
s. His interests encompassed the spin-statistics theorem, Kac-Moody and W-algebras, and included early contributions to the theory of non-invariance (dynamical) groups, among much else. His long and productive career in the application of symmetry methods to theoretical physics was acknowledged by the award of the Wigner Medal in August 2000.
Irish people
The Irish people are an ethnic group who originate in Ireland, an island in northwestern Europe. Ireland has been populated for around 9,000 years , with the Irish people's earliest ancestors recorded having legends of being descended from groups such as the Nemedians, Fomorians, Fir Bolg, Tuatha...
physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
of worldwide repute in the field of theoretical particle physics. He is best known for the O'Raifeartaigh Theorem, an important result in unification theory, and the O'Raifeartaigh Model of supersymmetry breaking
Supersymmetry breaking
In particle physics, supersymmetry breaking is the process to obtain a seemingly non-supersymmetric physics from a supersymmetric theory which is a necessary step to reconcile supersymmetry with actual experiments. It is an example of spontaneous symmetry breaking...
.
O'Raifeartaigh was born in Dublin in 1933, and most of his scientific career was centred around that city, where he obtained his first degrees at University College Dublin
University College Dublin
University College Dublin ) - formally known as University College Dublin - National University of Ireland, Dublin is the Republic of Ireland's largest, and Ireland's second largest, university, with over 1,300 faculty and 17,000 students...
(BA in 1953 and MSc in Mathematical Physics in 1956), and spent from 1968 until his death as Senior Professor at the Dublin Institute for Advanced Studies
Dublin Institute for Advanced Studies
The Dublin Institute for Advanced Studies Dublin, Ireland was established in 1940 by the Taoiseach of the time, Éamon de Valera under the . The Institute consists of 3 schools: The , the and the . The directors of these schools are currently Professor Werner Nahm, Professor Luke Drury and...
. He obtained his doctorate from the University of Zurich
University of Zurich
The University of Zurich , located in the city of Zurich, is the largest university in Switzerland, with over 25,000 students. It was founded in 1833 from the existing colleges of theology, law, medicine and a new faculty of philosophy....
in 1960, under Walter Heitler
Walter Heitler
Walter Heinrich Heitler was a German physicist who made contributions to quantum electrodynamics and quantum field theory...
. He also visited many institutions, notably Madras, IHES Bures, and the Institute for Advanced Study
Institute for Advanced Study
The Institute for Advanced Study, located in Princeton, New Jersey, United States, is an independent postgraduate center for theoretical research and intellectual inquiry. It was founded in 1930 by Abraham Flexner...
in Princeton, New Jersey
Princeton, New Jersey
Princeton is a community located in Mercer County, New Jersey, United States. It is best known as the location of Princeton University, which has been sited in the community since 1756...
, but it was during an extended stay at Syracuse University
Syracuse University
Syracuse University is a private research university located in Syracuse, New York, United States. Its roots can be traced back to Genesee Wesleyan Seminary, founded by the Methodist Episcopal Church in 1832, which also later founded Genesee College...
(1964-8) that he made the discovery that established his reputation. This result, which became known as O'Raifeartaigh's no-go theorem, showed that it was impossible to combine internal and relativistic symmetries other than in a trivial fashion, thus ending a widespread quest by the particle physics community to achieve this fusion. The O'Raifeartaigh theorem was later generalized to a more famous result known as the Coleman-Mandula theorem.
O'Raifeartaigh's prolific career in theoretical physics was manifested by many fundamental contributions to the application of symmetries in particle physics
Particle physics
Particle physics is a branch of physics that studies the existence and interactions of particles that are the constituents of what is usually referred to as matter or radiation. In current understanding, particles are excitations of quantum fields and interact following their dynamics...
. In the 1970s he showed that the new supersymmetries could provide a mechanism (O'Raifeartaigh's mechanism) for circumventing his no-go theorem which had assumed only classical Lie group
Lie group
In mathematics, a Lie group is a group which is also a differentiable manifold, with the property that the group operations are compatible with the smooth structure...
symmetries. In the 1980s he applied non-Abelian gauge theory to the analysis of magnetic monopole
Magnetic monopole
A magnetic monopole is a hypothetical particle in particle physics that is a magnet with only one magnetic pole . In more technical terms, a magnetic monopole would have a net "magnetic charge". Modern interest in the concept stems from particle theories, notably the grand unified and superstring...
s. His interests encompassed the spin-statistics theorem, Kac-Moody and W-algebras, and included early contributions to the theory of non-invariance (dynamical) groups, among much else. His long and productive career in the application of symmetry methods to theoretical physics was acknowledged by the award of the Wigner Medal in August 2000.
External links
- Article about O’Raifeartaigh on the DIAS website
- Obituary, Physics TodayPhysics TodayPhysics Today, created in 1948, is the membership journal of the American Institute of Physics. It is provided to 130,000 members of twelve physics societies, including the American Physical Society...
, November 2001