IN RICORDO DI Bruno Zumino (1923-2014) Bruno Zumino was awarded the “Enrico Fermi” Prize of the Italian Physical Society in 2005. Courtesy of Mary K.Gaillard Bruno Zumino died in his home at Berkeley, 95% of the total mass-energy of the Universe. so-called Wess-Zumino Lagrangian. California, on June, 22nd 2014, at the age of 91. Supersymmetry is a strong candidate for As a final part of this tribute to Bruno Zumino He was an Emeritus Professor at Berkeley Physics beyond the Standard Model and even if I would like to make some personal University since 1994 and his name is today no particles predicted by this symmetry recollections. I had the privilege of being his mainly associated with the formulation of have been detected, there is still hope that they closest collaborator after J . Wess, with fourteen supersymmetry in our four-dimensional will show up in the TeV mass range, when the jointly published papers. This joint activity space- time. Supersymmetry is a highly Large Hadron Collider (LHC) at CERN reaches the covered different epochs of my career, from the non-trivial extension of the relativistic symmetry highest project energy (14 TeV). time of my Fellowships at CERN to the time of of elementary particle interactions, called Two years later, in 1976, supersymmetry my senior and distinguished status (at CERN Poincaré symmetry, which, among other was combined with the gravitational force, and UCLA). I was proud to share with him and things, leads to the conservation of energy and giving birth to supergravity and its stunning Gabriele Veneziano (CERN and Collège de momentum. Supersymmetry transforms bosons developments, including superstring theory France) the 2005 Enrico Fermi Prize awarded by into fermions and vice versa and it makes it and M-theory. The original formulation of the Italian Physical Society. When I visited him possible by the introduction of extra “fermionic” supergravity, by Dan Freedman (MIT), Peter van in 2008, as a Miller visiting professor at Berkeley, anticommuting dimensions then extending Nieuwenhuizen (Stony Brook) and myself (at the we started again to collaborate on aspects of ordinary relativistic Minkowski space-time to time at INFN-LNF, Frascati and Ecole Normale duality applied to Black Holes and in fact the last Superspace, a concept later introduced by the Supérieure) was soon followed by an elegant papers of his life were written together with me. late Nobel Laureate Abdus Salam (Imperial formulation by Bruno Zumino and Stanley His last trip to Europe, to attend a conference College and ITCP) and James Strathdee (ICTP). Deser ( Brandeis) using the so-called first-order as invited speaker, was in the summer of 2011, In his pioneering work with the Austrian formalism. on the occasion of the celebration of the 80th physicist Julius Wess, done when he was a In his last year at CERN Zumino, with Berkeley birthday of Raymond Stora, his friend and senior staff member at CERN (1968-1981), Bruno physicist Mary K. Gaillard, collaborated in a collaborator. In the proceedings of that meeting, Zumino formulated the first four-dimensional pioneering work on the application of duality a joint study with Stora on the algebraic quantum field theory, called the Wess-Zumino to field theories. Duality, a generalization of approach to anomalies was reported. model, and proved his renormalizability. “electric magnetic duality” which exchanges In May 2013, a conference in his honour, Infinities of perturbation theory were actually electric fields with magnetic fields, plays celebrating his 90th birthday, took place at shown to be milder than in non-supersymmetric a fundamental role in connecting diverse Berkeley. Many distinguished physicists spoke theories then giving rise to the so-called formulations of string theory and in relating on his behalf, including Fields Medalist E. Witten “non-renormalization theorems” whose weakly-coupled theories in one formulation to and Nobel Laureate S. Weinberg. Unfortunately original appearance was in papers written in strongly-coupled theories in other formulations. he became ill just before the beginning of the mid- seventies in several collaborations Going back to Zumino’s early life. He was born the meeting and he could only come to the with Wess, Jean Iliopoulos (Ecole Normale in Rome, Italy on 28th April 1923 and graduated inaugural banquet, where he sat near me. That Supérieure, Paris) and myself, at the time a CERN in Physics at the University of Rome in 1945. was the last occasion I saw him. post-doctoral Fellow. In his early years, when in Göttingen, he wrote Bruno Zumino won many other prestigious In a joint collaboration we solved the important papers, together with Gerhart Luders, International Prizes, among them the Dirac problems of combining supersymmetry with on the consequences of the CPT theorem in Medal (1987), the APS Dannie Heineman Prize non-Abelian (Yang-Mills) gauge symmetry, relativistic quantum field theories. Then, in (1988), the 1989 Max Planck Medal, the 1992 then opening the way to apply supersymmetry 1951, he moved to New York University where Wigner Medal and the 1999 Giancarlo Wick Gold to the fundamental non-gravitational forces, the he remained until 1968 (also as Chair of the Medal. electroweak and strong interactions. Physics Department) when he joined the Theory He is survived by his wife Mary K. Gaillard and The case of supersymmetry for our Division at CERN. three stepchildren. low-energy world was mostly advocated to In those years he wrote important He leaves an enormous legacy and he will solve the so-called naturalness and hierarchy papers on “Field Algebras” with the Nobel be remembered for his achievements by future problems, but other important areas where Laureate T. D. Lee and on “phenomenological generations. I sincerely hope that his predictions supersymmetry could play an important role is Lagrangians” with S. Coleman (Harward), J. Wess and discoveries will be proved by Nature. in the formulation of Grand Unified Theories and (Karlsruhe) and C. G. Callan (Princeton). When he in providing some candidates for Dark Matter, moved to CERN he then wrote a fundamental Sergio Ferrara a form of elusive matter not reactant to light paper with J. Wess on the treatment of local CERN, Geneva, Switzerland which, together with dark energy, makes up gauge anomalies and the introduction of the .