"FEYNMAN DIAGRAMS" TRACED BACKWARD IN TIME
Binder,Yevgeny;Karcz,Maciej;Gangopadhyaya,Asim;Goltsiker,Aleksandr D.*;Mallow,Jeffry V.
(Submission #173)
Abstract
Complementing the recently published David Keiser book, "Drawing Theories Apart: The Dispersion of Feynman Diagrams in Postwar Physics"(U. Chicago Press, Spring 2005, 376p.), we will concentrate on the early history of QED (1940-1949). Contrary to H.A.Bethe's remark made in 1991,"..the methods of Richard Feymnan...[consisted of]... using Feynman graphs and the concept of positrons propagating backward in time", it is widely acknowledged by most authors of history of QED development, including Feynman himself, that this last cornerstone and breakthrough concept (alternative to Dirac's interpretation of antiparticles) was introduced by Stueckelberg (Switzerland) as early as 1941-1942 (in French). Feynman traced it to an unpublished private communication by his own Ph.D. advisor J.A.Wheeler (1940-41). We have found that this idea was first introduced (published in Russian in 1940) by Gregory Zisman (1912-1981). Zisman started out as a graduate student of V. Fock, and finished his doctoral degree under Ya. Frenkel. In 1946, Schonberg, a German emigree to USA who later moved to Brazil, also toyed with the idea of moving backward in time. Pioneering work of these two authors were quoted by Koba and Takeda (in English, early 1949), close collaborators of Tomonaga. Tomanaga's papers, thanks to D. Kaiser and others, became widely known in USA. Clearly the idea was already in the air! As for the famous diagrams, their name as "Feynman's" was coined at the end of 1949, just following the publication of Feynman's papers (first they were referred to as "Dyson" or as "Feynman-Dyson" graphs). This coinage was widely spread through numerous papers, theses, seminars and early books (1952-1955) from the Cornell University (Bethe's group), and Institute for Advanced Study, Princeton (Oppenheimer's circle). In Wentzel's book (1943 in German, 1949-English translation) and in some QED reviews and historical essays, Stueckelberg (1942) was thought to be the originator of the idea of "proto-diagrams". D.Ivanenko (1954) traced the idea as early as to Dirac's note (1933 in Russian). However, we show that the entire concept (the idea, technique and usage) should be attributed to G. Zisman's papers of 1940 and 1941, in which he first introduced these diagrams for such processes as pair creation, Compton scattering, and scattering of light on light. He then used them as graphical representations of different terms in the quantum interaction energy calculation (similar to Feynman's first picture in 1949). Referring to Zisman's 1940 paper, Koba and Takeda introduced (early 1949) a similar diagram technique (in momentum representation) to calculate radiative corrections. One then wonders whether the introduction of these ideas and methods were delayed (7-8 years in case of Zisman and Stueckelberg's or 1 year in case of Feynman) due to the resistance from the previous generation of QED founders (such as Fock to Zisman in 1939 and Bohr and Dirac in 1948) or as D. Kayser suggested it was some kind of "invisible college" conspiracy from the Cornell-Princeton circle which guided the propagation of these methods.