The dilemma of attribution.

I suspected that there were some members of the live audience who were somewhat apprehensive about sitting through the morning’s physics lectures. After all, there were three guys there to talk about one minus sign. If it were just two people and a plus sign, , one could talk about the and the other about the –. However, to my mind, this year’s awards represent or symbolize not just a minus sign, but a large body of significant advances in our understanding of fundamental physics, and are the work of not just three people but a great many scientists, stretching out over many years and many countries. This is really a prize for that whole community. Sidney Coleman, my beloved teacher from graduate school, referred to this community as i fratelli fisici, by which he meant the brotherhood of physicists. Most of us spoke at least a bit of broken Italian, a legacy of the grand and highly influential summer schools organized by Nino Zichichi in Erice, Sicily. Indeed, one of my fondest reflections on my particle physics career is having been able to arrive at a train station, virtually anywhere in the world, and be greeted by a total stranger who immediately treated me like an old friend. I’d love to tell you all their stories, but I certainly don’t know them all, nor do I have time (or space) even for those that I do. So I’ve chosen a few of the people and a few of the stories with which to make a particular point. You can judge for yourself at the end how well I’ve succeeded. And I’ll deal mostly with theorists because I know them best—although I must say that I do regard theoretical physics as a fundamentally parasitic profession, living off the labors of the real physicists. I’d like to address one particular aspect of the impact of these prizes. To a considerable extent, they have come to represent milestones in the progress of science. And it is a testament to the care and wisdom exercised in the selection process just how important the prizes have become. To the public, they spark continued interest in science’s most important advances. But even within the world of the scientific experts, the prizes likewise serve as markers of this progress. The use of history in science education may be a contributing factor to why this is so and how it works. As teachers of the next generation of scientists, we always seek to compress and simplify all of the developments that have come before. We want to bring our students as quickly as possible to the frontier of current understanding. From this perspective, the actual history, which involves many variants and many missteps, is only a hindrance. And the neat, linear progress, as outlined by the sequence of gleaming gems recognized by Nobel prizes, is a useful fiction. But a fiction it is. The truth is often far more complicated. Of course, there are the oft-told priority disputes, bickering over who is responsible for some particular idea. But those questions are not only often unresolvable, they are often rather meaningless. Genuinely independent discovery is not only possible, it occurs all of the time. Sometimes a yet harder problem in the prize selection process is to identify what is the essential or most important idea in some particular, broader context. So, it’s not just a question of who did it, i.e., who is responsible for the work, but what ‘‘it’’ is. In other words, what is the significant ‘‘it’’ that should stand as a symbol for a particularly important advance. I’ve no interest in recounting my whole life’s story or even my physics career. Rather, I want to focus on the context of the particular work cited in this year’s awards. So, I begin this saga with a trip I took with Erick Weinberg, a fellow graduate student, friend, and something of a mentor (he was a year ahead of me) from Cambridge, Massachusetts to Hoboken, New Jersey (I think it was 1970) to a conference to hear our teacher, Sidney Coleman, speak. He was delivering a paper titled ‘‘Why Dilatation Generators Don’t Generate Dilatations.’’ We had read a written version, but hoped that his talk would help us understand it better. It was a several-hour drive. Somewhere along the way, I asked Erick to explain to me a bit about what were called Yang–Mills or non-Abelian gauge theories. I had heard the name but was otherwise ignorant. They’d been invented in 1954 and were the last and least understood entry in a short list of what came to be considered the only possible descriptions of fundamental particle interactions. Erick explained the defining basics, but told me that nothing was known about their consequences and that many of the most famous senior particle theorists had gotten seriously confused about them. (The list of such notables included Dick Feynman, Shelly Glashow, Abdus Salam, and Steve Weinberg.) And now it seemed that no senior physicist wanted to discuss them; their ignorance and confusion were too embarrassing. (While delivering my talk live in Stockholm, it occurred to me I should have had a little light or a bell that went off when I mentioned a Nobel laureate—because part of my point is to try to understand who is and who isn’t. The relevant names are already familiar to the physicist segment of the audience, but for the sake of the general audience, I just raised my finger discretely. Here I’ll use a superscript N. So far, there’s Yang, Feynman, Glashow, Salam, Steve Weinberg, but not Coleman or Erick Weinberg.) It turns out there was one brave soul, Tini Veltman, who never gave up on Yang–Mills theory, and, with his bestever grad student, Gerard ’t Hooft, cracked the case in 1971. I think it worth noting that I, personally, know of no one who claimed to understand the details of ‘t Hooft’s paper. Rather, we all learned it from Ben Lee, who combined insights from his own work (that renormalization constants are independent of the choice of ground state in such theories), from hitherto unnoticed work from Russia (Fadde’ev and Popov on quantization and Feynman rules), and from the simple encouragement from ’t Hooft’s paper that it was possible. (It is amazing how much easier it can be to solve a problem once you are assured that a solution exists!) The bit of physics I remember best from the Hoboken conference was from a talk by T. D. Lee. He spoke with confidence that the weak interactions were mediated by a heavy bosonic particle that carried the force, and he gave its mass. (Several years later, he was proven right.) The clearest version of