Stanley Mandelstam

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Stanley Mandelstam UNIVERSITY OF CALIFORNIA, BERKELEY, DEPT OF PHYSICS Gor’kov will be remembered as an ac- one of the youngest participants invited complished scientist, a devoted mentor, to the prestigious 1961 Solvay Confer- and a gifted author, a man and artist ence on Physics, which celebrated the whose gentle personality and keen sense 50th anniversary of the famous inaugu- of humor are treasured by those who had ral 1911 conference. the pleasure of his company. Stanley returned to Berkeley in 1963 Greg Boebinger as a professor in the department of National High Magnetic Field Laboratory physics. Among the groundbreaking Florida State University work he produced during his 31-year Tallahassee career, there was the development of the Sergey Iordansky precursor for the discovery of string the- Landau Institute for Theoretical Physics ory, the elucidation of mechanisms for Chernogolovka, Russia quark confinement in quantum chromo- dynamics, the nonperturbative construc- David Pines tions of the bosonization (or fermioni - Santa Fe Institute zation) in (1 + 1)-dimension QFTs, and Santa Fe, New Mexico the proof of the perturbative UV finite- Lev Pitaevskii ness and β = 0, in any gauge to all orders, University of Trento of N = 4 supersymmetric Yang–Mills Trento, Italy theory. In 1992 he published the long- Kapitza Institute for Physical Problems Stanley Mandelstam awaited first proof of the perturbative Moscow, Russia UV finiteness of string theory, so string theory can be considered as a contender edge about functions of more than one for the theory of quantum gravity. Stanley Mandelstam complex variable. His presentation of the In 1994 Stanley became a professor paper at the 1958 American Physical So- emeritus. Until his death he continued to heoretical physicist Stanley Mandel- ciety meeting in Washington, DC, caught do research, to use his department office, Tstam died on 11 June 2016 in Berkeley, the attention of Geoffrey Chew. The two and to live in the same Berkeley apart- California. He was a leading expert met after Stanley finished his talk. At the ment that he had been in since 1980. and contributor to quantum field theory end of their discussion, Chew offered Stanley is being remembered admir- (QFT), the S-matrix approach, and string Stanley a researcher position at the Uni- ingly by his colleagues in Berkeley’s phys - theory. His influences on theoretical and versity of California, Berkeley, and Stan- ics department (http://physics.berkeley mathematical physics are deep and di- ley accepted right away. .edu/remembering-stanley-mandelstam) verse and cut across almost all current Stanley had two productive years at and by his colleagues, students, and major research efforts to deepen our Berkeley. He consolidated the Mandel- friends in the forthcoming Memorial Vol- understanding of the physical universe. stam representation into its final form ume for Stanley Mandelstam, edited by Born in 1928 in Johannesburg, South with the Mandelstam variables, worked Nathan Berkovits, Lars Brink, Kok Khoo Africa, Stanley obtained a BSc in chemi- with Chew to implement the representa- Phua, Charles Thorn, and me (World cal engineering from the University of tion into the S-matrix approach that Scientific). Witwatersrand in 1952. He switched his Chew and his collaborators had devel- Stanley’s influences live on. In his studies to theoretical physics at Trinity oped, and initiated the idea of using quiet, polite, attentive, and kind way, College, Cambridge University, from Regge poles for high-energy behaviors in Stanley won the respect and love of his which he obtained a BA in 1954. Two S-matrices. colleagues and friends. He is deeply years later he earned a PhD from the In 1960 Stanley returned to Birming- missed. University of Birmingham under adviser ham as a professor. His research output Ling-Lie Chau (喬玲麗) Rudolf Peierls. continued at a spectacular pace. During University of California, Davis PT Stanley continued his research at the next two years, with Berkeley and Birmingham for another year before Birmingham colleagues, he published moving to New York City. From 1957 to papers that consolidated the S-matrix 1958 he was a Boese research fellow in approach. He not only delved deeper RECENTLY POSTED NOTICES AT the department of physics at Columbia into the complex plane of angular mo- www.physicstoday.org/obituaries University. The next four years, 1958–62, mentum with Regge poles and cuts, but Mildred Dresselhaus can be called Stanley’s miracle years. he also pioneered two far-reaching new 1 November 1930 – 20 February 2017 In a 1958 paper, he initiated what we directions: the gauge-invariant path- M. K. Sundaresan now know as the Mandelstam represen- dependent fields for quantum gauge 2 September 1929 – 30 January 2017 tation in the Mandelstam variables for theories and the coordinate-independent S-matrices. It was a daring leap from the path-dependent fields for quantum Thomas Dombeck insights Stanley had gained from pertur- Einstein gravity. For both, he developed 7 February 1945 – 4 November 2016 bative results in QFT, the subject of his their Feynman rules in 1968. Paul Peercy thesis, and from his advanced knowl- Because of his achievements, he was 26 November 1940 – 20 October 2016 MAY 2017 | PHYSICS TODAY 69.
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