Knocking on Heaven's Door (24 page)

Even at a conference that took place in December 2009, that was purportedly about dark matter, participants were eagerly commenting on the LHC—which had just completed its incredibly successful debut of acceleration and collisions. At the time, after the near despair of a little more than a year before, everyone was ecstatic. Experimenters were relieved they had data they could study to understand their detectors better. Theorists were happy they might get some answers before too long. Everything was working fabulously well. The beams looked good. Collisions had occurred. And experiments were recording events.

However, reaching this landmark was quite a story, and this chapter tells the tale. So fasten your seat belt. It was a bumpy ride.

A SMALL WORLD AFTER ALL

The story of CERN precedes that of the LHC by several decades. Soon after the end of World War II, a European accelerator center that would host experiments studying elementary particles was first conceived. At that time, many European physicists—some of whom had immigrated to the United States and some of whom were still in France, Italy, and Denmark—wanted to see cutting-edge science restored to their original homelands. Americans and Europeans agreed that it would be best for scientists and science if Europeans joined together in this common enterprise and returned research to Europe so they could repair the residue of devastation and mistrust remaining after the recently ended war.

At a UNESCO conference in Florence in 1950, the American physicist Isidor Rabi recommended the creation of a laboratory that would reestablish a strong scientific community in Europe. In 1952, the Conseil Européen pour la Recherche Nucléaire (hence the acronym CERN) was set up to create such an organization, and on July 1, 1953, representatives from twelve European nations came together to create the institution that became known as “the European Organization for Nuclear Research,” and the convention establishing it was ratified the following year. The CERN acronym clearly no longer reflects the name of the research center. And we now study subnuclear, or particle, physics. But as is often true with bureaucracy, the initial legacy remained.

The CERN facility was deliberately built centrally in Europe on a site crossing the Swiss-French border near Geneva. It’s wonderful to visit if you like the outdoors. The fabulous setting includes farmland and the Jura Mountains immediately nearby and the Alps readily accessible in the distance. CERN experimenters are on the whole a rather athletic bunch, with their easy access to skiing, climbing, and biking. The CERN site is quite large, covering enough territory for an exhausting run to keep those athletic researchers in shape. The streets are named after famous physicists, so you can drive on Route Curie, Route Pauli, and Route Einstein on a visit to the site. The architecture at CERN was, however, a victim of the time in which it was built, which was the 1950s with bland International Style low-rises, so CERN buildings are rather plain with long hallways and sterile offices. It didn’t help the architecture that it was a science complex—look at the science buildings on most any university and you will usually find the ugliest buildings on campus. What enlivens the place (along with the scenery) are the people who work there and their scientific and engineering goals and achievements.

International collaborations would do well to study CERN’s evolution and its current operations. It is perhaps the most successful international enterprise ever created. Even in the aftermath of World War II, when the countries had so recently been in conflict, scientists from twelve different nations joined together in this common enterprise.

If competition played any role at all, it was primarily directed against the United States and its burgeoning scientific endeavors. Until experiments at CERN found the
W
and
Z
gauge bosons, almost all particle physics discoveries had come from accelerators in America. The drunken physicist who walked into the common area at Fermilab where I was a summer student in 1982 saying how they “had to find the bloody vector bosons” and destroy America’s dominance probably expressed the viewpoint of many European physicists at the time—though perhaps somewhat less eloquently and definitely with poorer diction.

CERN scientists did find those bosons. And now, with the LHC, CERN is the undisputed center of experimental particle physics. However, this was by no means predetermined when the LHC was first proposed. The American Superconducting Supercollider (SSC) that President Reagan approved in 1987 would have had almost three times the energy—had Congress continued its support. Although the Clinton administration initially didn’t support the project initiated by its Republican predecessors, that changed as President Clinton better understood what was at stake. In June 1993, he tried to prevent the cancellation in a letter to William Natcher, chairman of the House Committee on Appropriations, in which he said, “I want you to know of my continuing support for the Superconducting Super Collider (SSC)…. Abandoning the SSC at this point would signal that the United States is compromising its position of leadership in basic science—a position unquestioned for generations. These are tough economic times, yet our Administration supports this project as a part of its broad investment package in science and technology…. I ask you to support this important and challenging effort.” When I met the former president in 2005, he brought up the subject of the SSC and asked what we had lost in abandoning the project. He quickly acknowledged that he too had thought that humanity had forfeited a valuable opportunity.

Around the time that Congress killed the SSC, taxpayers ponied up about $150 billion to pay for the savings and loan crisis, which far exceeded the approximately $10 billion the SSC would have cost. The U.S. annual deficit in comparison amounts to a whopping $600 per American, and the Iraq War to more than $2,000 per citizen. With the SSC we would have had high-energy results already, and we would have reached far higher energies even than the LHC will achieve. With the end of the S&L crisis we left ourselves open to the financial crisis of 2008 and a bailout that was even more expensive to taxpayers.

The LHC’s price tag of $9 billion was comparable to the SSC’s proposed cost. It amounts to about $15 per European—or as my colleague Luis Álvarez-Gaumé at CERN likes to say, about a beer per European per year during the construction time of the LHC. Assessing the value of fundamental scientific research of the sort taking place at the LHC is always tricky, but fundamental research has spurred electricity, semiconductors, the World Wide Web, and just about all technological advances that have significantly affected our lives. It also inspires technological and scientific thinking, which spreads into all aspects of our economy. The LHC’s practical results might be difficult to anticipate, but the science potential is not. I think we can agree that the Europeans in this case are more likely to get their money’s worth.

Long-term projects require belief, dedication, and responsibility. Such commitments are becoming increasingly hard to come by in the United States. Our past vision in the U.S. led to tremendous scientific and technological advances. However, this type of essential long-term planning is becoming increasingly rare. You have to hand it to the European Community for their ability to continue to see their projects through. The LHC was first envisioned a quarter century ago and approved in 1994. Yet it was such an ambitious project that only now is it reaching fruition.

Furthermore, CERN has successfully broadened its international appeal to include not only the 20 CERN member states, but also 53 additional nations that have also participated in the design, construction, and testing of instruments—and scientists from 85 countries currently participate. The United States isn’t an official member state, but there are more Americans than any other single nationality working on the major experiments.

About 10,000 scientists participate in total—perhaps about half of the total number of particle physicists on Earth. One-fifth of them are full-time employees who live nearby. With the advent of the LHC, the main cafeteria has become so packed that you could barely order food without your tray hitting another physicist—a problem that a new cafeteria extension now helps alleviate.

With its international population, an American arriving at CERN will be struck by the many languages and accents reverberating in the cafeterias, offices, and hallways. The Americans will also notice the cigarettes, cigars, wine, and beer there, which also remind them they’re not at home. Some comment as well on the superior quality of the cafeterias, as did one of my freshman students who had worked there over the summer. Europeans, with their more refined palates, tend to find this assessment somewhat questionable.

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 magnets on an industrial scale to keep highly accelerated protons circulating in the ring. As we observed in the previous chapter, the existing tunnel size presented the biggest technical challenge, since its radius was fixed and magnetic fields therefore had to be very big. In his talk, Lyn happily described the “Swiss watch precision” of the first 10-meter-long prototype dipole magnet that engineers and physicists successfully tested in 1994. They reached 8.73 tesla on their first shot, which was their target and a very promising sign.

Unfortunately, however, although European funding is more stable than that of the United States, unforeseen pressures introduced uncertainties for CERN’s finances as well. The budget for Germany, which contributes the most to CERN, suffered from the 1990 reunification. Germany therefore reduced its contributions to CERN, and, along with the United Kingdom, didn’t want to see any major increase in the CERN budget. Christopher Llewellyn Smith—the British theoretical physicist who succeeded the Nobel Prize—winning physicist Carlo Rubbia as CERN director general—was, like his predecessor, strongly supportive of the LHC. By acquiring funding from Switzerland and France, the two host states that stood to benefit the most from the LHC’s construction and operation in their home territory, Llewellyn Smith partially alleviated the serious budget issues.

The CERN Council was appropriately impressed—both with the technology and with the budget resolution—and approved the LHC soon afterward on December 16, 1994. Llewellyn Smith and CERN furthermore convinced nonmember states to join and participate. Japan came on board in 1995, India in 1996, and soon after Russia and Canada, with the United States following in 1997.

With all the contributions from Europe and other nations, the LHC could override a proviso in the original charter that called for construction and operation in two phases, the first of which would involve only two-thirds of the magnets. Both scientifically and in terms of total cost, the reduced magnetic field would have been a poor choice. But the original intention was to allow budgets to balance every year. In 1996, when Germany again reduced its contribution due to its reunification costs, the budget situation again looked grim. However, in 1997, CERN was allowed to compensate for the loss by financing construction with loans for the first time.