Knocking on Heaven's Door - Lisa Randall [75]
The many employees and visitors at CERN range from engineers to administrators to the many physicists who actually do the experiments and the more than 100 physicists who participate in the theory division at any given time. CERN is structured hierarchically, with the chief officers and council responsible for all policy matters, including major strategic decisions. The head is known as the director general (DG) which perhaps has the ring of something out of Gilbert and Sullivan, though the many directorships under the DG account for the name. The CERN Council is the ruling body responsible for major strategic decisions such as planning and scheduling projects. It pays special attention to the Scientific Policy Committee, which is the major advisory board that helps evaluate proposals and their scientific merit.
The large experimental collaborations, with thousands of participants, have a structure of their own. Work is distributed according to detector components or types of analyses. A given university group might be responsible for one particular piece of the apparatus or one particular type of potential theoretical interpretation. Theorists at CERN have more freedom than experimenters to work on whatever is of interest to them. Sometimes their work pertains to CERN experiments, but many of them work on more abstract ideas that won’t be tested anytime soon.
Nonetheless, all particle physicists at CERN and around the globe are excited about the LHC. They know their future research and the future of the field itself relies on the successful operation and discoveries of the next 10 to 20 years. They understand the challenges, but they also agree in their bones with the superlatives that go with this enterprise.
A BRIEF HISTORY OF THE LHC
Lyn Evans was the LHC’s chief architect. Though I’d heard him speak in his lovely lilting Welsh intonation the year before, I finally met him at a conference in California in early January 2010. This was an opportune time since the LHC was finally on track, and even for an understated Welshman, his pleasure was obvious.
Lyn gave a wonderful talk about the roller-coaster ride he’d had since first setting out to build the LHC. He began by telling us about the true inception of the idea in the 1980s, when CERN conducted the first official studies investigating the option of producing a high-energy proton-proton collider. He then told about the 1984 meeting that most people consider the idea’s official initiation. Physicists at that time met with machine builders in Lausanne to introduce the idea of colliding together proton beams with 10 TeV of energy—a proposal that was scaled down to 7 TeV beams in the final implementation. Almost a decade later, in December 1993, physicists presented an aggressive plan to the CERN Council, the governing body at CERN over major strategic decisions, to build the LHC during the next 10 years by minimizing all other experimental programs at CERN aside from LEP. At that time, the CERN Council turned it down.
Initially, one argument against the LHC had been the intense competition posed by the SSC. But that disappeared with the project’s demise in October 1993, at which time the LHC became the sole candidate for a very high-energy accelerator. Many physicists then became increasingly convinced of the significance of the enterprise. On top of that, machine research was extremely successful. Robert Aymar, who would ultimately head CERN during the LHC construction phase, chaired a review panel in November 1993 that concluded the LHC would be feasible, economical, and safe.
The critical hurdle in planning the LHC was developing strong enough