[{"@context":"http:\/\/schema.org\/","@type":"BlogPosting","@id":"https:\/\/wiki.edu.vn\/en\/wiki19\/kenneth-alan-johnson-wikipedia\/#BlogPosting","mainEntityOfPage":"https:\/\/wiki.edu.vn\/en\/wiki19\/kenneth-alan-johnson-wikipedia\/","headline":"Kenneth Alan Johnson – Wikipedia","name":"Kenneth Alan Johnson – Wikipedia","description":"From Wikipedia, the free encyclopedia American physicist Kenneth Alan Johnson (March 26, 1931 in Duluth, Minnesota \u2013 February 9, 1999","datePublished":"2016-04-19","dateModified":"2016-04-19","author":{"@type":"Person","@id":"https:\/\/wiki.edu.vn\/en\/wiki19\/author\/lordneo\/#Person","name":"lordneo","url":"https:\/\/wiki.edu.vn\/en\/wiki19\/author\/lordneo\/","image":{"@type":"ImageObject","@id":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","height":96,"width":96}},"publisher":{"@type":"Organization","name":"Enzyklop\u00e4die","logo":{"@type":"ImageObject","@id":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","url":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","width":600,"height":60}},"image":{"@type":"ImageObject","@id":"https:\/\/en.wikipedia.org\/wiki\/Special:CentralAutoLogin\/start?type=1x1","url":"https:\/\/en.wikipedia.org\/wiki\/Special:CentralAutoLogin\/start?type=1x1","height":"1","width":"1"},"url":"https:\/\/wiki.edu.vn\/en\/wiki19\/kenneth-alan-johnson-wikipedia\/","about":["Wiki"],"wordCount":3915,"articleBody":"From Wikipedia, the free encyclopediaAmerican physicistKenneth Alan Johnson (March 26, 1931 in Duluth, Minnesota \u2013 February 9, 1999 in Boston, Massachusetts) was an American theoretical physicist.\u00a0 He was Professor of Physics at MIT, a leader in the study of quantum field theories and the quark substructure of matter. \u00a0 Johnson contributed to the understanding of symmetry and anomalies in quantum field theories and to models of quark confinement and dynamics in quantum chromodynamics.[1]Table of ContentsBiography[edit]Early life[edit]Career at MIT[edit]Personal life[edit]References[edit]External links[edit]Biography[edit]Early life[edit]Ken Johnson was a student at Case Western Reserve University and obtained his bachelor’s degree from the Illinois Institute of Technology in 1952.\u00a0 He studied theoretical physics at Harvard University, completing his Ph. D. under the direction of Julian Schwinger in 1955.[2] \u00a0 Johnson remained at Harvard as a Research Fellow and Lecturer from 1955 through 1957 and during 1957-1958 he was an NSF Postdoctoral Fellow at the Institute for Theoretical Physics (Niels Bohr Institute), Copenhagen.[1]Career at MIT[edit]Johnson was appointed to the MIT faculty in 1958 as Assistant Professor, promoted to Associate Professor in 1961, and to Full Professor in 1965.\u00a0 Johnson remained at MIT, with the exception of visiting positions at SLAC (1971\u201372, 1980\u201381), University of Washington (1972), and Nordita (1981), for the remainder of his career.[citation needed]Early in his career, Johnson together with Marshall Baker (University of Washington) undertook a systematic study of the short distance and high energy behavior of quantum electrodynamics (QED), which presaged modern studies of renormalization group flow and the search for ultraviolet fixed points of the QED \ud835\udefd-function.[3][4]Johnson was one of the first to discover chiral and other anomalies in gauge-field theories,[5] anticipating the work of Stephen Adler (IAS), John Bell (CERN), and Roman Jackiw (MIT) on chiral anomalies.[6][7]\u00a0 Continuing his study of anomalies, Johnson, collaborating with Francis Low (MIT), introduced limiting methods for studying the short distance behavior of operator products.[8]\u00a0 Similar methods were introduced by James Bjorken (SLAC).[9]\u00a0 The Bjorken\u2013Johnson\u2013Low Limit was used extensively in the study of scaling and perturbative anomalies in the late 1960s and was subsumed into the more general framework of the operator product expansion by Kenneth Wilson.[10]\u00a0 Working with Jackiw, Johnson showed that gauge invariance could break down dynamically in a theory with massless fermions but without fundamental scalar particles, leading to mass generation for both the fermions and the gauge bosons.[11] This work formed the foundation for technicolor theories of compositeness beyond the Standard Model.[citation needed] Students at MIT include C. R. Hagen, co-discoverer of the Higgs mechanism and Higgs boson.In the early 1970s Johnson became interested in the confinement of quarks in theories of hadron structure.\u00a0 He led a collaboration with Alan Chodos, Robert Jaffe, Charles Thorn, and Victor Weisskopf (all MIT) in the development of a relativistic, gauge invariant, and heuristic model of quark confinement known as the \u201cMIT Bag Model\u201d,[12] which emerged as a standard model for describing hadrons in quantum chromodynamics (QCD). The MIT Bag Model provided a framework for the initial investigation of many aspects of the behavior of confined quarks and gluons in QCD.\u00a0 In several of these studies, Johnson played a leading role. Together with Thomas DeGrand (University of Colorado), Joseph Kiskis (UC Davis), and Jaffe, Johnson showed that the spectra of light-quark baryons and mesons could be accommodated in QCD.[13] With Thorn, Johnson demonstrated the emergence of string-like excitations of hadrons in QCD,[14] and Johnson and Jaffe explored the spectra and interactions of exotic hadrons composed purely of gluons or made of more than three quarks.[15]\u00a0 Studies of such unusual hadrons remains a topic of current experimental and theoretical interest.\u00a0 In his later years, Johnson focused on finding a heuristic description of the gluon field configurations that dominate the confining condensate in the QCD vacuum, a search that continues to this day.[citation needed]Personal life[edit]Ken Johnson was married to Gladys (Diaz de los Arcos) Johnson, who also studied physics at Harvard in the early 1950s.\u00a0 Gladys was an accomplished artist.\u00a0 They had one son, Keith Johnson.[1]References[edit]^ a b c “Professor Kenneth A. Johnson dies at 67; taught physics at MIT for 40 years”.^ “Mathematics Genealogy Project”.^ Johnson, Kenneth A. (1958-11-15). “Consistency of Quantum Electrodynamics”. Physical Review. 112 (4): 1367\u20131370. Bibcode:1958PhRv..112.1367J. doi:10.1103\/PhysRev.112.1367. ISSN\u00a00031-899X.^ Baker, M.; Johnson, K. (1969-07-25). “Quantum Electrodynamics at Small Distances”. Physical Review. 183 (5): 1292\u20131299. Bibcode:1969PhRv..183.1292B. doi:10.1103\/PhysRev.183.1292. ISSN\u00a00031-899X.^ Johnson, K. (1963). “\u03b35 invariance”. Physics Letters. 5 (4): 253\u2013254. Bibcode:1963PhL…..5..253J. doi:10.1016\/S0375-9601(63)95573-7.^ Bell, J. S.; Jackiw, R. (1969). “A PCAC puzzle: \u03c00\u2192\u03b3\u03b3 in the \u03c3-model”. Il Nuovo Cimento A. 60 (1): 47\u201361. Bibcode:1969NCimA..60…47B. doi:10.1007\/BF02823296. ISSN\u00a00369-3546. S2CID\u00a0125028356.^ Adler, Stephen L. (1969-01-25). “Axial-Vector Vertex in Spinor Electrodynamics”. Physical Review. 177 (5): 2426\u20132438. Bibcode:1969PhRv..177.2426A. doi:10.1103\/PhysRev.177.2426. ISSN\u00a00031-899X.^ Johnson, K.; Low, F. E. (1966). “Current Algebras in a Simple Model”. Progress of Theoretical Physics Supplement. 37: 74\u201393. Bibcode:1966PThPS..37…74J. doi:10.1143\/PTPS.37.74. ISSN\u00a00375-9687.^ Bjorken, J. D. (1966-08-26). “Applications of the Chiral U ( 6 ) \u2297 U ( 6 ) Algebra of Current Densities”. Physical Review. 148 (4): 1467\u20131478. Bibcode:1966PhRv..148.1467B. doi:10.1103\/PhysRev.148.1467. ISSN\u00a00031-899X.^ Wilson, Kenneth G. (1969-03-25). “Non-Lagrangian Models of Current Algebra”. Physical Review. 179 (5): 1499\u20131512. Bibcode:1969PhRv..179.1499W. doi:10.1103\/PhysRev.179.1499. ISSN\u00a00031-899X.^ Jackiw, R.; Johnson, K. (1973-10-15). “Dynamical Model of Spontaneously Broken Gauge Symmetries”. Physical Review D. 8 (8): 2386\u20132398. Bibcode:1973PhRvD…8.2386J. doi:10.1103\/PhysRevD.8.2386. ISSN\u00a00556-2821.^ Chodos, A.; Jaffe, R. L.; Johnson, K.; Thorn, C. B.; Weisskopf, V. F. (1974-06-15). “New extended model of hadrons”. Physical Review D. 9 (12): 3471\u20133495. Bibcode:1974PhRvD…9.3471C. doi:10.1103\/PhysRevD.9.3471. ISSN\u00a00556-2821.^ DeGrand, T.; Jaffe, R. L.; Johnson, K.; Kiskis, J. (1975-10-01). “Masses and other parameters of the light hadrons”. Physical Review D. 12 (7): 2060\u20132076. Bibcode:1975PhRvD..12.2060D. doi:10.1103\/PhysRevD.12.2060. ISSN\u00a00556-2821.^ Johnson, K.; Thorn, C. B. (1976-04-01). “Stringlike solutions of the bag model”. Physical Review D. 13 (7): 1934\u20131939. Bibcode:1976PhRvD..13.1934J. doi:10.1103\/PhysRevD.13.1934. ISSN\u00a00556-2821.^ Jaffe, R.L.; Johnson, K. (1976). “Unconventional states of confined quarks and gluons”. Physics Letters B. 60 (2): 201\u2013204. Bibcode:1976PhLB…60..201J. doi:10.1016\/0370-2693(76)90423-8.External links[edit]The Bag Model of Quark Confinement: \u00a0 Scientific American 241, No.1, 112 (1979).A Practical Model of Quark Confinement: Comments on Nuclear and Particle Physics, 7, No. 4, 107 (1977).  "},{"@context":"http:\/\/schema.org\/","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"https:\/\/wiki.edu.vn\/en\/wiki19\/#breadcrumbitem","name":"Enzyklop\u00e4die"}},{"@type":"ListItem","position":2,"item":{"@id":"https:\/\/wiki.edu.vn\/en\/wiki19\/kenneth-alan-johnson-wikipedia\/#breadcrumbitem","name":"Kenneth Alan Johnson – Wikipedia"}}]}]