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Symmetry schemes
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Symmetry schemes
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85. Global symmetry. Yang-Mill's theory. Phil Anderson | 1321 | 03:21 | |
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I think it was in ’57 that I proposed the global symmetry, and it didn't give a very good mass formula and of course I wasn't very happy with it. And its predicted power wasn't very great and of course, we know it was wrong. I assumed that some version of Yang-Mills theory was to be used for both the weak interaction and the strong interaction. The big problem with that, which got more and more serious over the years, until color made its appearance, was that the two got in each others way if they operated in the same space of charges, and… and that was a serious obstacle to thinking that both the strong and the weak interactions were somehow Yang-Mills theories.
[Q] You weren't concerned about the mass loss in itself, the gauge bosons?
Well, I knew that you had to modify the Yang-Mills theory if you wanted to get the intermediate boson for the weak interactions along with the photon. You had to violate its symmetry somehow and get massive particles. I didn't know how to do that. When I wrote my Eightfold Way pre-print in January 1961 I actually advertised for what I called a soft mass mechanism. But this was a year or two after my collaborators and I had used the sigma model as an example of a number of things. And of course starting from the sigma model it's very easy to get to the correct explanation of how the Yang-Mills theory can have its symmetry violated in a soft manner so as not to violate renormalizability. Salam and Kumar in London, Imperial College, while I was visiting there or near the time when I was visiting there in ’59 and '60, pointed out that Yang-Mills theory would be okay, renormalizable, if… if the symmetry weren't broken; but if it were broken in any brute force manner, just by sticking in a mass for the bosons, for example, then it was no longer renormal izable. So it was clear that a soft mass mechanism was needed and well , if I had been thinking carefully I probably would have found it a lot earlier than… than it was found, but… but I didn't. Playing with the sigma model we were very, very close to… to the correct answer. Actually it was Phil Anderson working in condensed matter physics who found the mechanism for getting a massive intermediate boson. The so-called Higgs, Kibble and so on and so on and so on mechanism should also be named after Anderson. And I said in my book, kidding him, that if the elementary particle physics community had given him adequate credit for this idea he… we would have been spared his public objections to the construction of new accelerators.
New York-born physicist Murray Gell-Mann (1929-2019) was known for his creation of the eightfold way, an ordering system for subatomic particles, comparable to the periodic table. His discovery of the omega-minus particle filled a gap in the system, brought the theory wide acceptance and led to Gell-Mann's winning the Nobel Prize in Physics in 1969.
Title: Global symmetry. Yang-Mill's theory. Phil Anderson
Listeners: Geoffrey West
Geoffrey West is a Staff Member, Fellow, and Program Manager for High Energy Physics at Los Alamos National Laboratory. He is also a member of The Santa Fe Institute. He is a native of England and was educated at Cambridge University (B.A. 1961). He received his Ph.D. from Stanford University in 1966 followed by post-doctoral appointments at Cornell and Harvard Universities. He returned to Stanford as a faculty member in 1970. He left to build and lead the Theoretical High Energy Physics Group at Los Alamos. He has numerous scientific publications including the editing of three books. His primary interest has been in fundamental questions in Physics, especially those concerning the elementary particles and their interactions. His long-term fascination in general scaling phenomena grew out of his work on scaling in quantum chromodynamics and the unification of all forces of nature. In 1996 this evolved into the highly productive collaboration with James Brown and Brian Enquist on the origin of allometric scaling laws in biology and the development of realistic quantitative models that analyse the influence of size on the structural and functional design of organisms.
Tags: Eightfold Way, Imperial College, London, Abdus Salam, Phil Anderson
Duration: 3 minutes, 21 seconds
Date story recorded: October 1997
Date story went live: 24 January 2008