Robert Brout

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Robert Brout
Robert Brout.jpg
Born(1928-06-14)June 14, 1928
New York City, USA
DiedMay 3, 2011(2011-05-03) (aged 82)
Brussels, [1] Belgium
NationalityBelgian
Alma mater New York University (BS)
Columbia University (PhD)
Known for Quantum field theory
Symmetry breaking
Higgs boson
Higgs mechanism
Cosmic inflation
Awards Sakurai Prize
Wolf Prize in Physics (2004)
Scientific career
Fields Statistical mechanics
Particle physics
Cosmology
Institutions Université libre de Bruxelles
University of Rochester
Cornell University

Robert Brout ( /brt/ ; June 14, 1928 – May 3, 2011) was a Belgian theoretical physicist who made significant contributions in elementary particle physics. He was a Professor of Physics at Université Libre de Bruxelles where he had created, together with François Englert, the Service de Physique Théorique.

Contents

Research

After receiving his Ph.D. from Columbia University in 1953 Brout joined Cornell University as faculty. In 1959 François Englert visiting from Belgium spent two years at Cornell as a research associate with Brout. Brout and Englert became close friends and collaborators, and in 1961 when Englert returned to Belgium Brout followed him and spent the rest of his professional life at the Université Libre de Bruxelles, and ultimately acquired Belgian citizenship.

In 1964, Brout, in collaboration with Englert, discovered how mass can be generated for gauge particles in the presence of a local abelian and non-abelian gauge symmetry. This was demonstrated by them, both classically and quantum mechanically, successfully avoiding theorems initiated by J. Goldstone while indicating that the theory would be renormalizable. Similar ideas have been developed in condensed matter physics.

Peter Higgs and Gerald Guralnik, C. R. Hagen, and Tom Kibble came to the same conclusion as Brout and Englert. The three papers written on this boson discovery by Higgs, Brout and Englert, and Guralnik, Hagen, Kibble were each recognized as milestone papers by Physical Review Letters 50th anniversary celebration. [2] While each of these famous papers took similar approaches, the contributions and differences between the 1964 PRL symmetry breaking papers is noteworthy. This work showed that the particles that carry the weak force acquire their mass through interactions with an all-pervasive field that is now known as the Higgs field, and that the interactions occur via particles that are widely known as Higgs bosons. As yet, these Higgs bosons had not been observed experimentally; however, most physicists believed that they exist. [3] [4] On July 4, 2012, it was announced at CERN that a new particle, "consistent with a Higgs boson", had been discovered with 5 sigma confidence in the mass region around 125-126 GeV. [5] In 2013 Englert and Higgs were to receive the Nobel Prize in Physics for their prediction.

In 1971, Gerardus 't Hooft, who was completing his PhD under the supervision of Martinus J. G. Veltman at Utrecht University, renormalized Yang–Mills theory in accordance with Veltman's suggestion that this was possible. They showed that if the symmetries of Yang–Mills theory were to be broken according to the method suggested by Robert Brout, François Englert, Peter W. Higgs, Gerald Guralnik, C. R. Hagen and Tom Kibble then Yang–Mills theory is indeed renormalizable. Renormalization of Yang–Mills theory is one of the biggest achievements of twentieth century physics. Gerardus 't Hooft and Martinus J. G. Veltman were awarded the Nobel Prize in Physics in 1999 for this work. [6]

In addition to this work on elementary particle physics, in 1978, Brout, in collaboration with F. Englert and Edgard Gunzig, was awarded the first prize gravitational award essay [7] for their original proposal of cosmic inflation as the condition of the cosmos prior to the adiabatic expansion, (i.e. the conventional Big Bang), after cosmogenesis.

Awards

Brout was awarded the 2010 J. J. Sakurai Prize for Theoretical Particle Physics (with Guralnik, Hagen, Kibble, Higgs, and Englert) by The American Physical Society "For elucidation of the properties of spontaneous symmetry breaking in four-dimensional relativistic gauge theory and of the mechanism for the consistent generation of vector boson masses." [8] In 2004, Robert Brout, François Englert, and Peter Higgs were awarded the Wolf Prize in Physics "for pioneering work that has led to the insight of mass generation, whenever a local gauge symmetry is realized asymmetrically in the world of sub-atomic particles". [9]

Robert Brout contributed greatly to the theory behind the Higgs Boson, for which the 2013 Nobel Prize was awarded. In a 2014 interview with BBC's The Life Scientific Peter Higgs says of the 2013 Nobel Prize that "I think it's good that they restricted the prize to the two of us, because, by implication, they're recognizing Robert Brout as the third who couldn't be awarded the prize." [10]

Related Research Articles

Electroweak interaction Unified description of electromagnetism and the weak interaction

In particle physics, the electroweak interaction or electroweak force is the unified description of two of the four known fundamental interactions of nature: electromagnetism and the weak interaction. Although these two forces appear very different at everyday low energies, the theory models them as two different aspects of the same force. Above the unification energy, on the order of 246 GeV, they would merge into a single force. Thus, if the universe is hot enough (approximately 1015 K, a temperature not exceeded since shortly after the Big Bang), then the electromagnetic force and weak force merge into a combined electroweak force. During the quark epoch, the electroweak force split into the electromagnetic and weak force.

Weak interaction Interaction between subatomic particles

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Gerald Guralnik

Gerald Stanford "Gerry" Guralnik was the Chancellor’s Professor of Physics at Brown University. In 1964 he co-discovered the Higgs mechanism and Higgs boson with C. R. Hagen and Tom Kibble (GHK). As part of Physical Review Letters' 50th anniversary celebration, the journal recognized this discovery as one of the milestone papers in PRL history. While widely considered to have authored the most complete of the early papers on the Higgs theory, GHK were controversially not included in the 2013 Nobel Prize in Physics.

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The Higgs boson is an elementary particle in the Standard Model of particle physics produced by the quantum excitation of the Higgs field, one of the fields in particle physics theory. It is named after physicist Peter Higgs who in 1964 along with five other scientists proposed the Higgs mechanism to explain why some particles have mass.. This mechanism required that a spinless particle known as a boson should exist with properties as described by the Higgs Mechanism theory. This particle was called the Higgs boson. A subatomic particle with the expected properties was discovered in 2012 by the ATLAS and CMS experiments at the Large Hadron Collider (LHC) at CERN near Geneva, Switzerland. The new particle was subsequently confirmed to match the expected properties of a Higgs boson.

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References

  1. Biography of Robert Brout Physics Today . August 2011. Retrieved July 5, 2012.
  2. Physical Review Letters - 50th Anniversary Milestone Papers
  3. Contributions of Robert Brout Retrieved August 6, 2007. Archived February 11, 2007, at the Wayback Machine
  4. "Wolf prize goes to particle theorists". Physics World . January 20, 2004. Retrieved August 6, 2007.
  5. "CERN experiments observe particle consistent with long-sought Higgs boson" (Press release). July 4, 2012. Retrieved November 20, 2016.
  6. The Nobel Prize in Physics 1999 Retrieved August 6, 2007.
  7. Gravity Research Foundation Awards Archived 2007-09-29 at the Wayback Machine Retrieved May 24, 2008.
  8. American Physical Society - J. J. Sakurai Prize Winners Retrieved October 2, 2009.
  9. The Wolf Prize in Physics in 2004 Retrieved August 6, 2007.
  10. Interview with Peter Higgs on BBC's The Life Scientific BBC News. Retrieved August 6, 2007.