François Englert was born in 1932 in Etterbeek (Belgium). He went to the Athenée Royal de Koekelberg in Brussels before joining the Ecole Polytechnique of the Applied Sciences Faculty at the Université Libre de Bruxelles where he got a degree in electro-mechanical engineering in 1955, followed by a degree in physical sciences from the Faculty of Sciences in 1958 and a PhD in Sciences the following year. He left for Cornell University in 1959 as a Research Associate and was made Assistant Professor the following year. He worked under the supervision of Robert Brout, who would become a life-long collaborator. He came back to the Université Libre de Bruxelles in 1961, first as a Junior Lecturer and then Full Professor starting 1964. Joined in Brussels by Robert Brout, they created and headed the Service de Physique Théorique starting 1980. He became Professor Emeritus in 1998.
Together with Robert Brout, he developed in 1964 the so-called Brout-Englert-Higgs mechanism to explain how some particles may get a mass, a mechanism also proposed by Peter W. Higgs from Edimburg University. This mechanism involves the existence of a scalar particle or Brout-Englert-Higgs boson. The search of this particle has been a major goal in particle physics for many decades, and in particular since the start of the LHC at CERN. François Englert has received many prizes and honours for this work: the Francqui Prize in 1982, the High Energy and Particle Prize of the European Physical Society in 1997 (together with Robert Brout and Peter Higgs), the Wolf Prize for Physics in 2004 (with Robert Brout and Peter Higgs), the J.J. Sakurai Prize of the American Physical Society in 2010 (with R. Brout, P.W. Higgs, G. Guralnik, C.R. Hagen and Th. Kibble) and in 2013 the Prince of Asturias Award for Technical and Scientific Research (together with P.W. Higgs and CERN).
The name of François Englert is also associated to cosmic inflation, a phase of accelerated expansion of that could have occurred in the early universe, and would explain how it became homogeneous and isotropic on large scales. His work of 1977, “The Causal Universe”, together with Robert Brout and Edgard Gunzig, has received in 1978 a first award for an essay in gravitation from the Gravity Research Foundation.
In 2013, the King Albert II of Belgium has made him Baron.
Discovery of a new elementary particle at CERN!
On the 4th of July 2012, the CERN has announced the discovery of a new elementary particle by the ATLAS and CMS collaborations at the LHC. The complementary analysis, presented in March 2013 at the Moriond meetings, have revealed that the properties of this new particle (which has a mass of about 126 GeV/c2) are in agreement with those expected for the Brout-Englert-Higgs boson.
This particle is a keystone of the Standard Model of particle physics, the most accurate and complete theory ever developed to explain the laws of fundamental interactions in Nature. The mathematical coherence of this theory has been established at the beginning of the seventies by Gerard ‘t Hooft and Martinus Veltman (both received the Nobel Prize in 1999 for their work) and by Jean Zinn-Justin and Benjamin W. Lee.
The mechanism of symmetry breaking, which is an essential part of the Standard Model, shows how both short-range interactions, like the weak interaction observed in radioactive decays, and long-range interactions, like electromagnetism actually have a common origin. On the basis of this idea, Sheldon Glashow, Abdus Salam and Steven Weinberg have build a theory unifying the weak and electromagnetic interactions, for which they received the Nobel Prize in 1979. The W and Z gauge bosons predicted by this theory have been discovered at CERN in 1983. The 1984 Nobel Prize for Physics has been awarded to Rubbia and Simon van der Meer for their essential contributions to these discoveries.
The exceptional importance of the work of Robert Brout, François Englert and Peter W. Higgs, has been recognized through many prestigious prizes and awards:
- The Francqui Prize has been awarded in 1982 to François Englert for, among other things “his contribution to the theoretical understanding of symmetry breaking in fundamental physics, in which, together with Robert Brout, he has been the first to show that the mechanism of spontaneous symmetry breaking in gauge theories give mass to gauge particles…”;
- The European Physical Society High Energy and Particle Physics Prize was awarded to Brout, Englert and Higgs in 1997, “for formulating for the first time a self-consistent theory of charged massive vector bosons which became the foundation of the electroweak theory of elementary particles»;
- The Wolf Foundation Prize in Physics was awarded to them in 2004 “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»;
- The J.J. Sakurai Prize for Theoretical Physics of the American Physical Society was awarded in 2010 jointly to Brout, Englert, Guralnik, Hagen, Higgs, and Kibble “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;
- le Prince of Asturias Awards for Technical and Scientific Research was attributed in 2013 to Englert and Higgs, jointly with CERN.
It is also interesting to note that the unique merits of Brout, Englert and Higgs are recognized by the Nobel Committee in the review article “Scientific Background on the Nobel Prize in Physics 2008”, published by the Royal Swedish Academy of Sciences. The 2008 Nobel Prize being awarded to Yoichiro Nambu, the Committee states: “The same ideas (as by Nambu) were tried in 1964 for relativistic gauge theory by Robert Brout and François Englert and also by Peter Higgs. They found that spontaneously broken gauge symmetry, as in the nonrelativistic version of Nambu, does not produce a massless particle. Instead, this mechanism gives the vector field a mass and a scalar state, the still today hypothetical Higgs particle, which is also a characteristic feature of such a theory».
Boson de Higgs and Boson de Brout-Englert-Higgs: as statement by Steven Weinberg
In a contribution released in May, 2012, on the site of the New York Review of books, Steven Weinberg, 1979 Nobel Prize, comes back to the history: “In his recent book, The Infinity Puzzle (Basic Books, 2011), Frank Close points out that a mistake of mine was in part responsible for the term “Higgs boson.” In my 1967 paper on the unification of weak and electromagnetic forces, I cited 1964 work by Peter Higgs and two other sets of theorists. (…)
As to my responsibility for the name “Higgs boson,” because of a mistake in reading the dates on these three earlier papers, I thought that the earliest was the one by Higgs, so in my 1967 paper I cited Higgs first, and have done so since then. Other physicists apparently have followed my lead. But as Close points out, the earliest paper of the three I cited was actually the one by Robert Brout and François Englert. In extenuation of my mistake, I should note that Higgs and Brout and Englert did their work independently and at about the same time, as also did the third group (Gerald Guralnik, C.R. Hagen, and Tom Kibble). But the name “Higgs boson” seems to have stuck.”
Chronology of the articles associated to the Brout-Englert-Higgs boson
The particle discovered at CERN in 2012 has all the characteristics expected for the Brout-Englert-Higgs boson of the Standard Model. Of course, measurements will be improved, and will allow determining whether we are confronted to the minimal version of the Standard Model or one of its many possible extensions, but it is by now already clear that the visionary contribution of Robert Brout, François Englert, and Peter Higgs has been confirmed. It brings some sorrow, remembering that Robert Brout passed away in May 2011, only about a year before the discovery of the new particle.