Probably the best thing that ever happened to Carlo Rubbia was being placed as runner-up by an Italian university appointments panel. Ever since failing to win a chair – he had his eye on a vacancy at Lecce University – Rubbia has become the archetypal larger-than-life globe-trotting physicist, best known for the discovery in 1983 of the W and Z bosons at CERN, the European particle physics lab in Geneva. Since sharing the 1984 Nobel prize for this discovery, he has been director-general of CERN and the d riving force behind a host of other experiments, initiatives and committees.

Rubbia gets a mixed press: everyone agrees that he is a genius and a trail-blazer but few disagree that he can be stubborn and arrogant. Rubbia himself admits that he has “more enemies than anyone else”. “Brilliant, uncompromising,difficult to work with, passionate and dar-ing,” says Nicola Cabibbo, the particle theorist who is now chairman of ENEA, the Italian agency for new technologies, energy and the environment.

In his book The God Particle, Leon Lederman, the Nobel-prize-winning US particle physicist, describes Rubbia’s presentations as “an intimate mixture of blarney, bravado, bombast, and sub-stance”. Rubbia himself admits that he has “more enemies than anyone else”. Although still fascinated by particle physics, he now wants to pay his dues to society by working on what he sees as the main problem for the future – energy.After “years of administration and power struggles”, Rubbia has returned to the”real pleasure of doing science for what-ever science is worth it”.

Born in 1934 in Gorizia, near Italy’s border with Slovenia, Rubbia studied at the acclaimed Scuola Normale in Pisa in the 1950s. After spells at Columbia University in New York and the University of Rome, he joined CERN as a research physicist in 1960 and has been associated with the Geneva lab ever since. In 1970 he was made a professor at Harvard University in the US and for 18 years taught one semester there each year. “I loved teaching; I miss it a lot now, “he told Physics World.

Today Rubbia is a senior research scientist at CERN with his own group dedicated to experimental research on an energy amplifier (a reactor driven by neutrons that burns thorium and plutonium to produce uranium and energy). Plans to build a prototype of the reactor in Spain were announced recently. Rubbia also played a key role in the construction of the Elettra synchrotron radiation source in Trieste and is still involved in neutrino experiments at CERN and the Gran Sasso underground laboratory in Italy.

It was at CERN that Rubbia’s first major tour de force paid off. By the mid-1970s it was clear that the most important challenge in particle physics was to detect the W and Z bosons predicted by the electroweak theory of Glashow, Salam and Weinberg. In the late 1970s, Rubbia and colleagues proposed an experiment to search for these particles in proton-antiproton collisions at the super proton synchrotron at CERN.

“The problem was to get more energy, which was solved by using a ring for collisions instead of firing particles at a tar-get,” he recalls. “The other problem was to get 10” antiprotons, cold and ready togo every morning – in those days anti-protons were really hard to get. We had to invent a revolutionary accelerator. Simon [Van der Meer] was the deus ex machina who figured out how to get those anti-protons into the ‘sardine can’ so that I could use them.” Van der Meer shared theNobel prize with Rubbia for developing the stochastic cooling technique that made Rubbia’s experiments possible.

Rubbia is still intrigued by particle physics and is particularly fascinated by neutrinos: “Neutrinos are considered to be zero mass. The mass of the photon has to be zero, otherwise electrodynamics would go to hell,” he says. “But the mass of the neutrino is zero out of ignorance, not theory.”

Rubbia is keen to send a beam of neutrinos from CERN to the Gran Sasso underground laboratory, 730 km away in Italy. A 3-ton prototype experiment has been demonstrated successfully at CERN, but proposals to build the 600-ton ICARUS detector at Gran Sasso are still under consideration (Physics World November 1996 pp8-9).

Soon after his Nobel prize work, Rubbia’s attention turned to plans to build a synchrotron radiation source in Italy. He chaired the working group whose proposals led to Elettra, the third-generation source that came on-line in Trieste in 1993. Rubbia’s determination and willingness to take risks were demonstrated when he took out a massive L70 bn (about £25 m) bankloan to finish construction, after endless delays in government funding forced the project into debt in the early 1990s. His gamble paid off – Elettra opened ahead of schedule and the cash eventually came through to pay off the loan.

Rubbia ended his involvement in Elettra last year with the source outperforming its design specification, over-subscribed by satisfied users, and with its books balancing for the first time ever. Giorgio Margaritondo, a physicist at the Ecole Polytechnique Federale de Lausanne in Switzerland and co-ordinator of the experimental division at Elettra, says that Rubbia’s involvement in the project was “a complete success – technical, scientific and financial – under extraordinarily difficult circumstances”.

Vladimir Keilis-Borok, director of the international geophysics institute in Moscow, is equally impressed by Rubbia’s involvement in the INTAS project to help scientists in the former Soviet Union. “Rubbia invested his brilliance, prestige, and compassion in the initiative, applying the same uncompromisingly high standards that he observed in science. When he saw that the initiative was running effectively, Rubbia resigned graciously to pursue other trail-blazing interests,” he says.

Along with his work for Elettra and at CERN, Rubbia has always been a member of endless boards and committees, in both the public and private sector. Recent examples include the boards of Alitalia, Olivetti, the San Paolo Foundation and the so-called Rubbia committee, which was set up in 1995 to review the research programme of ASI, Italy’s problematic space agency.

Rubbia now heads a group at CERN dedicated to research on an energy amplifier. This is a reactor driven by neutrons that burns thorium and plutonium to produce uranium and energy. The project has no special funding and Rubbia is coy about where the money comes from: “We get by somehow but money is not the central issue here. The central issue is to find the underlying scientific background, and to concentrate on ideas.” Work on the project is also carried out at Elettra, where it is funded by various agencies in Italy, France and the Netherlands.

So what attracted Rubbia to the energy experiment? “Fundamental science now has a function within society which is somewhat different from what it used to be,” he says. “In the past we only had to provide knowledge, no matter how much it cost, and no matter how long it would take. Today, people are increasingly concerned about the rising cost of science.” He also believes that many processes that influence the quality of life – such as pollution and climate change – revolve around energy.  “Energy is something that physicists invented and I think we have a major responsibility to find ways and means to perhaps invent new things that would improve on the environmental impact of energy,” he says.

And what will Carlo do next? Every time the government changes in Italy – and it changes frequently – he is mentioned as possible science minister. But Rubbia does not seem interested. Others, including Giorgio Salvini – Rubbia’s one-time super-visor at Rome University and subsequently Italy’s science minister – doubt if Rubbia is cut out to be a politician.

Stories about Rubbia abound. Lederman, for example, recalls a sign that read “No Swimming. Carlo is using the ocean” appearing on the beach near a conference on Long Island. But construction of a more lasting legacy, the Large Hadron Collider, is due to start at CERN in 2000. Rubbia was chairman of the committee which presented the LHC proposal to the CERN council in 1987, and was a prime mover behind the project during his term as director-general.Others may have taken up the running but Rubbia is still making waves.