In August 1992 high-energy physicists gathered in Dallas, Texas, for the 26th meeting in a series known as the Rochester conferences. The conference was hosted by the Superconducting Super Collider (SSC) laboratory, which was under construction in Waxahachie, a small town 40 km south of Dallas.
In normal times, the occasion would have been considered an auspicious one for high-energy physics. But the mood among the delegates was somber. The US House of Representatives had spoken out against the SSC project, pointing to its rising cost and the undue pressure it would put on other areas of science. Members of the Senate, however, had rallied to support the high-energy community.
The opening remarks at the conference included a keynote address by William Happer, representing the US Department of Energy. Despite Happer's eloquent and balanced talk, it was hard to escape the conclusion that high-energy physicists had their backs to the wall. A year later, the SSC project was cancelled.
The conference itself had interesting moments. New results were pouring out of CERN's Large Electron–Positron Collider that tested electroweak theory with ever-greater precision. Studies of jets—narrow cones of hadrons and other particles produced in collisions—and heavy quarks were testing quantum chromodynamics. The value of a key parameter in QCD, the running coupling constant, was in sight. George Smoot described the COBE observations of the microwave background. Steven Weinberg lucidly summarized the conference.
Outside the lecture halls, I was struck by the efficiency of the conference organizers and by the friendliness of ordinary Texans. In hotels, restaurants, and taxis, people would smile whenever they saw our SSC conference badges. Participants were treated to a violin concert by Pinchas Zukerman. And perhaps most memorably, we were taken on a tour of the SSC site, where we could stare in awe at the enormous cavern that had been excavated and at the beginnings of the tunnel that would house the particle accelerator.
My own contribution to the conference was a ten-minute talk in which I reported a result obtained in a paper written with Manfred Wanninger, my first PhD student. Our paper drew attention to the decay of the KL meson into a pion, antipion, electron, and positron. Wanninger predicted that the distribution of the angle between the pion–antipion and electron–positron planes would contain an asymmetric term that was simultaneously odd under CP and time reversal. The predicted asymmetry was 14%.
Wanniger's result was surprising and provocative. Until then, the only source of CP violation considered was a tiny 2 × 10−3 CP impurity in the KL wave function. The paper had been accepted for publication and was due to appear in Physical Review D. Explaining the subtle effect in a ten-minute talk was difficult, but I had hoped to arouse enough curiosity that people would read the paper and that experimenters, in particular, would consider looking for the effect.
When I returned to the Institute for Theoretical Physics in Aachen, Germany, I found among the conference materials a curious souvenir: a Japanese-style hand fan made of cardboard and wood. When I waved the fan, it produced a gentle breeze. Although the fan was easy to dismiss as frippery, I preserved it as a memento. I thought of it as a good-luck charm, and it remained on my desk for many years.
In August 1997, exactly five years after the Dallas conference, I was attending the European Physical Society Conference on High-Energy Physics, which was being held that year in Jerusalem. A colleague from Aachen told me that a physicist from Fermilab had been trying to contact me during my absence. Returning from the conference, I found an email from Brad Cox, one of the members of the the KTeV experiment at Fermilab. Cox wrote:
My group has observed the K_L --> pipiee decay in the data we recently took in the KTeV experiment. The bottom line is that we see very clearly the CP violating asymmetry in the angle between the normals to the e+e- and pi+pi- planes that you predicted in PR D46 of August 92. The data are very pretty and agree with your predictions very well.
A year later the experimenters presented their official result at the Heavy Quark 98 conference in Fermilab. My friend Ikaros Bigi sent me the following message:
Mike Arenton (Virginia) has just given the talk for the KTeV collaboration. Their asymmetry after acceptance corrections is 13.5 +/- 2.5 +/- 3.0%. YOU MUST BE QUITE PLEASED.
I had reason to be pleased. The good-luck charm from Waxahachie was doing its work.
In the years that followed, my desk in the institute became crowded with paper. The souvenir from Dallas disappeared from view. In the spring of 2012, I was in my seventh year of retirement and decided to vacate my office, which had been my workplace for 35 years. There was an enormous quantity of paper and junk that had to be cleared. While preparing to throw away a pile of papers, I saw the missing memento: It was trapped in the pages of an old preprint. I took it home and placed it near my computer.
Three months later, on 4 July 2012, a momentous event occurred at CERN. Holding stage in the CERN auditorium were Fabiola Gianotti and Joe Incandela, representing, respectively, the ATLAS and CMS experiments at the LHC, each of which involved thousands of physicists from laboratories and Institutes around the world. The two speakers had just presented compelling evidence for a new particle that looked like the Higgs boson. The auditorium erupted in ovation. Physicists following the webcast, in places as far-flung as Chicago, Beijing, Mumbai, and Melbourne, cheered and raised toasts. Newspaper journalists had a field day. Discarding the shackles of scientific accuracy and rectitude, they wrote giddily about god particles and cosmic molasses.
I followed the proceedings on my computer at home. The souvenir that had been designed in honor of the SSC, was also on the table. On a day when Americans traditionally look at fireworks in the sky, the eyes of physicists were riveted by images of microscopic fireworks produced in collisions of particles a hundred meters underground.
As I glanced at the souvenir that had kept me company for 20 years, I imagined that the breeze of that little fan when I first waved it had been one of hope and optimism. On 4 July 2012, as the world of physics rejoiced, it was possible to believe that the memento from Waxahachie had fulfilled its promise.
