Roman Jackiw
Encyclopedia
Roman W. Jackiw is a theoretical physicist
and Dirac Medallist. Born in Poland
, Jackiw received his PhD from Cornell University
in 1966 under Hans Bethe
and Kenneth Wilson. He has been a professor at MIT Center for Theoretical Physics
since 1969.
Jackiw is famous for the discovery of the so-called axial anomaly
, also known as Adler-Bell-Jackiw anomaly
, also known as the Chiral anomaly. In 1969, Roman Jackiw and John Stewart Bell
published their explanation, which was later expanded and clarified by Stephen L. Adler
, of the (observed) decay of a neutral pion
into two photon
s. This decay is forbidden by a symmetry of classical electrodynamics, but Bell and Jackiw showed that this symmetry cannot be preserved at the quantum level.
Their introduction of an "anomalous" term from quantum field theory
required that the sum of the charges of the elementary fermion
s had to be zero. This work also gave important support to the color-theory of quark
s. Jackiw is also known for Jackiw–Teitelboim gravity
also called the "R=T model".
His son Stefan Jackiw
is an American violinist.
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...
and Dirac Medallist. Born in Poland
Poland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
, Jackiw received his PhD from Cornell University
Cornell University
Cornell University is an Ivy League university located in Ithaca, New York, United States. It is a private land-grant university, receiving annual funding from the State of New York for certain educational missions...
in 1966 under Hans Bethe
Hans Bethe
Hans Albrecht Bethe was a German-American nuclear physicist, and Nobel laureate in physics for his work on the theory of stellar nucleosynthesis. A versatile theoretical physicist, Bethe also made important contributions to quantum electrodynamics, nuclear physics, solid-state physics and...
and Kenneth Wilson. He has been a professor at MIT Center for Theoretical Physics
MIT Center for Theoretical Physics
MIT Center for Theoretical Physics is a subdivision of MIT Laboratory for Nuclear Science and Department of Physics. Current research areas in the center include particle physics, string theory, nuclear physics, lattice QCD, cosmology and quantum computing...
since 1969.
Jackiw is famous for the discovery of the so-called axial anomaly
Anomaly (physics)
In quantum physics an anomaly or quantum anomaly is the failure of a symmetry of a theory's classical action to be a symmetry of any regularization of the full quantum theory. In classical physics an anomaly is the failure of a symmetry to be restored in the limit in which the symmetry-breaking...
, also known as Adler-Bell-Jackiw anomaly
Chiral anomaly
A chiral anomaly is the anomalous nonconservation of a chiral current. In some theories of fermions with chiral symmetry, the quantization may lead to the breaking of this chiral symmetry. In that case, the charge associated with the chiral symmetry is not conserved.The non-conservation happens...
, also known as the Chiral anomaly. In 1969, Roman Jackiw and John Stewart Bell
John Stewart Bell
John Stewart Bell FRS was a British physicist from Northern Ireland , and the originator of Bell's theorem, a significant theorem in quantum physics regarding hidden variable theories.- Early life and work :...
published their explanation, which was later expanded and clarified by Stephen L. Adler
Stephen L. Adler
Stephen Louis Adler is an American physicist specializing in elementary particles and field theory.-Biography:Adler was born in New York City. He received an A.B. degree at Harvard University in 1961, where he was a Putnam Fellow, and a Ph.D. from Princeton University in 1964...
, of the (observed) decay of a neutral pion
Pion
In particle physics, a pion is any of three subatomic particles: , , and . Pions are the lightest mesons and they play an important role in explaining the low-energy properties of the strong nuclear force....
into two photon
Photon
In physics, a photon is an elementary particle, the quantum of the electromagnetic interaction and the basic unit of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force...
s. This decay is forbidden by a symmetry of classical electrodynamics, but Bell and Jackiw showed that this symmetry cannot be preserved at the quantum level.
Their introduction of an "anomalous" term from quantum field theory
Quantum field theory
Quantum field theory provides a theoretical framework for constructing quantum mechanical models of systems classically parametrized by an infinite number of dynamical degrees of freedom, that is, fields and many-body systems. It is the natural and quantitative language of particle physics and...
required that the sum of the charges of the elementary fermion
Fermion
In particle physics, a fermion is any particle which obeys the Fermi–Dirac statistics . Fermions contrast with bosons which obey Bose–Einstein statistics....
s had to be zero. This work also gave important support to the color-theory of quark
Quark
A quark is an elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. Due to a phenomenon known as color confinement, quarks are never directly...
s. Jackiw is also known for Jackiw–Teitelboim gravity
Jackiw–Teitelboim gravity
The R=T model, also known as Jackiw–Teitelboim gravity is a theory of gravity with dilaton coupling in one spatial and one time dimension. It should not be confused with the CGHS model or Liouville gravity...
also called the "R=T model".
His son Stefan Jackiw
Stefan Jackiw
-Biography:Stefan Jackiw was born in Boston, Massachusetts, to a Korean mother and a German father of Ukrainian origin, both physicists. His mother, So-Young Pi, teaches at Boston University, and his father, Roman Jackiw, at MIT. His surname, pronounced jack-eev, is of Ukrainian origin...
is an American violinist.