A leap into the superworld

The first success was achieved in 1971 by Ramond, who constructed a string analogue of the Dirac equation. Shortly afterwards, Neveu and Schwarz constructed a new bosonic string theory. They realized that the two constructions were different facets of a single theory - an interacting superstring theory containing Neveu and Schwarz's bosons and Ramond's fermions.

In 1972 Schwarz demonstrated the consistency of the theory in 10 dimensions. It was in the study of this theory that algebras with both commutators and anticommutators first appeared in the western literature. A supersymmetry on the two-dimensional string world sheet was recognized by Gervais and Sakita in 1971. This property of the boson and fermion fields on the string world sheet was called the supergauge invariance, which was probably the first application of the prefix "super" in this context. The Gervais-Sakita supergauge invariance in two dimensions was the point of departure for Wess and Zumino. Starting in 1973, Wess and Zumino wrote a series of revolutionary papers that set the course for future research. Among these was the construction of a "modern" linear version of supersymmetry in four dimensions. They suggested a scalar-spinor model, which now goes under the name of the Wess-Zumino model. They also formulated the linear version of the supersymmetric extension to QED. In fact, as we know now, string theory contains local four-dimensional supersymmetry (supergravity), but string theorists were very slow to realize this.

The realization came only after supersymmetry in four dimensions was studied thoroughly. In these initial stages the geographic distribution of supersymmetry practitioners was very skewed. The lion's share of early research was carried out at CERN, Trieste, London and Paris. The name "supersymmetry" was coined by Salam and Strathdee in Trieste in 1974. It first appeared in the title of their paper that was devoted to supersymmetric gauge theories.

In the body of the paper they settled for the old-fashioned name, "supergauge". Subsequent progress was rapid. In a series of papers, Wess and Zumino; Iliopoulos and Zumino; and Ferrara, Iliopoulos, and Zumino described miraculous cancellations concerning the renormalizability of supersymmetric theories. The superspace/superfield formalism was worked out by Salam and Strathdee. Key non-renormalization theorems were proven by West and others.

Non-Abelian gauge theories were supersymmetrized, simultaneously, by Ferrara and Zumino; and Salam and Strathdee in 1974. Mechanisms for the spontaneous breaking of supersymmetry through F- and D-terms were found by O'Raifeartaigh; and Fayet and Iliopoulos. The foundations of what is now known as the minimal supersymmetric standard model were laid by Fayet.

Supergravity was being developed in parallel. This culminated in 1976 with the publication of two papers by Ferrara, Freedman and van Nieuwenhuizen; and Deser and Zumino. These authors assembled various "superelements" that were in circulation at that time, completing the elegant construction of modern supergravity.

A detailed account of the early history of supersymmetry can be found in The Supersymmetric World: the Beginnings of the Theory, which has just been published by World Scientific.

Last October, Minnesota's Theoretical Physics Institute hosted a symposium and workshop celebrating 30 years of supersymmetry. The opening days featured many of the founding fathers of supersymmetry, including Evgeny Likhtman, Vladimir Akulov and Vyacheslav Soroka representing the Eastern origins of supersymmetry.

From the West, speakers included Pierre Ramond, Jean-Loup Gervais, Bunji Sakita, Pierre Fayet, John Iliopoulos, Lochlainn O'Raifeartaigh, Sergio Ferrara, Peter Van Nieuwenhuizen, Martin Sohnius, S James Gates, John Schwarz, Peter West, Bernard de Wit, Ali Chamsedine, Bernard Julia and Gabriele Veneziano. These historical accounts of, or by, early participants whose successes and failures shaped the modern understanding of high-energy physics, were both emotional and instructive.

One focal presentation was the talk delivered by Mrs Koretz-Golfand, the widow of Yuri Golfand, who shared her recollections of her husband's life and work. This theme was continued by Evgeny Likhtman, Golfand's student. His talk combined anecdotal evidence with a summary of the Golfand-Likhtman results "before Wess-Zumino". It was also a remarkable testimony to how free scientific thought can resist the most oppressive of regimes.

For Evgeny Likhtman, this trip was his first to the West. The historical talks were intertwined with topical reviews devoted to the most exciting modern developments.