The Last Man Who Knew Everything

by David N. Schwartz

  Is this state of affairs truly a legacy of Enrico Fermi? If Fermi had perished somewhere in the Atlantic during the voyage on the Franconia over New Year’s 1938–1939, the Manhattan Project would have eventually moved forward, perhaps more slowly and certainly in different ways. Facing the situation they did, US political leaders decided to go ahead with the Manhattan Project, a decision neither surprising nor obviously evil. The decisions surrounding the use of the bomb in the wake of Germany’s surrender were made at the highest level, with only cursory attention paid to the views of scientists. President Truman knew that he alone bore responsibility for the decision to use these weapons against enemy cities.

  This is not to let Fermi or his colleagues “off the hook” in any sense. For better or worse, they changed the future for us all. The Manhattan Project scientists have, however, assumed a greater burden of guilt than they deserve. If history is to judge Fermi and his colleagues for their wartime work, it should be with a more nuanced perspective that appreciates the situation they faced and their motivations for participating.

  The other great legacy of that wartime project is the nuclear reactor. Fermi may not have invented the atomic bomb, but he and Szilard most certainly did invent the nuclear reactor. Some 450 electric power reactors operate worldwide, with 60 more under construction. About one hundred are in the United States. However, only five US reactors have come on line since 1990. The decline in the use of nuclear power in the United States and elsewhere is mainly the result of high-profile nuclear accidents around the world, including those at Three Mile Island in 1979, Chernobyl in 1986, and the 2011 accident at Fukushima. These three notorious accidents, spread out over a period of three decades, have done as much as anything to kill the prospects of nuclear energy in the United States. Yet the technology advances. Engineers at Argonne Lab, Fermi’s old stomping ground, have designed modern fast breeder reactors that produce fuel as they consume it. An initial load of fuel could, in principle, last one thousand years and produces no greenhouse gases at all. South Korea, where the nuclear allergy is less severe, is in the process of building such reactors in consultation with Argonne engineers. The future of nuclear energy in the United States is uncertain at best. Whether future generations of Americans will reconsider the option of pursuing safe nuclear energy remains to be seen.

  Reactors have purposes other than providing nuclear energy. They provide the main way modern medical radioisotopes are created. Corbino was prescient. He understood the commercial value of the slow-neutron discovery for medical purposes. He never anticipated, however, that his greatest student would invent a virtual radioisotope factory. By irradiating specific elements inside research reactors, medical physicists create substances that can be used to trace the presence of cancer as well as to treat cancer once it is found. Countless lives have been saved through these techniques. More than a dozen research centers around the world produce these isotopes in reactors that can trace their lineage directly to those dusty piles of graphite and uranium that rose up from the floor in the basement of Schermerhorn Hall at Columbia and the squash court at Stagg Field at Chicago, under the watchful eye of Enrico Fermi.

  FERMI’S PATH TO GREATNESS DIFFERED FROM THAT OF EINSTEIN, Bohr, Planck, or any of the others who created modern physics. It started from a profound confidence that he could solve any problem thrown his way and that nature would ultimately disclose her most precious secrets to his probing mind. That confidence was based on an incredibly solid foundation of knowledge laid down early in his life through intense and disciplined effort, under the guidance of mentors and professors who understood and cultivated his greatness. He understood that there were no shortcuts to deep understanding and was willing to make a radical commitment to gain that understanding.

  The sturdy foundation of his knowledge informed his taste in the types of problems he studied. He had an unerring instinct for the “next big thing,” and the decisions he made about his own research agenda set the agenda for the field at large. This instinct led him to focus on the way in which the exclusion principle could be integrated into statistical mechanics. It then led him to focus on solving the beta decay crisis using quantum field theory. Next it led him to neutron experiments that would open up the field of nuclear physics. Finally, he understood that an accelerator that could produce beams of high-energy pions could be used to explore the nature of the strong force. That superb instinct, married to a foundation in the basics second to none, produced a wealth of lasting achievements.

  He also believed that anyone could learn what he knew. He believed this quite literally and lived his life devoted to that belief. In the process of digesting physics in his own way so that those around him could grasp it, he developed a technique of stripping problems to their bare essentials and leading his students through step-by-step solutions, ignoring complexities that would obscure the essence of the problems. This conviction ensured that the way he thought about physics influenced future generations of physicists.

  A constant theme throughout his career was the central role of probability and chance in his analytic framework. He became a deep student of probability early on, driven perhaps by the loss of his brother, a low-probability event with profound personal consequences. In the world of quantum theory all physicists must understand probability, but Fermi placed it front and center in his research, returning to it time and again—in the Fermi-Dirac statistics, in the Thomas-Fermi model of the atom, in his pen-and-paper analysis of neutron diffusion, and in his pioneering use of Monte Carlo methods to simulate physics problems. The Fermi Paradox—the conclusion that if life existed elsewhere in the universe, they should have visited us by now—is a classic example of how he could break down almost any problem into a series of probabilistic assumptions.

  He sacrificed much for physics. He was willing to compromise his political beliefs in exchange for the freedom to pursue physics without interference. He was willing to put his family life second to his career, with unhappy consequences. He may even have sacrificed his life, if we believe that his exposure to radiation had any relationship to his ultimate demise.

  Confidence born of innate ability and a strong foundation, a firm belief in his ability to solve any problem, an instinct for important research, an unshakeable faith in his ability to make others understand, a fascination with the role of probability and chance at the core of how the world works, the willingness to make enormous sacrifices for science—all these made Fermi who he was and contributed to his ability to make a lasting impact. Like all of us, however, scientists are prisoners of the era into which they are born. To have had the impact of Einstein, it helped to be born during a period when some of the deepest problems of physics had come to the fore. If Einstein had been born a century earlier, he may have achieved much, but certainly nothing of the magnitude of general relativity. It was Fermi’s great good fortune to have been born during a period in which the quantum revolution was unfolding.

  And yet that great good fortune had a darker side. As Fermi realized when he was young, one implication of the twentieth-century revolutions in physics was the enormous energy locked inside matter, energy that could blow to smithereens the first physicist to unleash it. He could hardly have realized that it would be his fate to be that first physicist. If every great gift has a price to be paid for it, this was certainly a major one: the field he loved, and pursued with such passion for his entire adult life, uncovered a secret of nature that gave man the ability to destroy the world. Another price was one with which other driven professionals are familiar: the neglect of family relationships in pursuit of compelling career objectives. In many ways Fermi paid for his great gift, but this was an inevitable cost of that gift and the time in which he lived.

  GEOFFREY CHEW AND UGO AMALDI HAVE BOTH DESCRIBED Fermi AS “the last man who knew everything.” Obviously, he did not know everything. His knowledge of science beyond physics was superficial, and his knowledge of history, literature, art, music, and much else besides
was limited, to say the least. He was not a universal genius.

  He did, however, know everything about physics. In his day that was rare enough. Chandrasekhar marveled that Fermi, with no prior background in astrophysics, could jump into the field relatively late in life and make significant contributions. He should not have been surprised. Fermi loved all aspects of physics and he lived at a time—perhaps the last time—when it was possible for someone with the proper background and innate ability to master all of physics. Fermi did so, not only across all subdisciplines of the field—astrophysics, nuclear physics, particle physics, condensed matter physics, even geophysics—but across theory and experiment. In this, he was truly unique. He saw physics as an integrated whole, comprehensible through a handful of powerful analytical tools he worked hard to master. Today physicists rarely talk across subdisciplines, and when they do they have increasing difficulty understanding each other. Even in Fermi’s day, theorists and experimentalists had trouble seeing the world from each other’s perspective. Today the problem is compounded by the magnitude and complexity of experiments and the increasingly sophisticated mathematics involved in cutting-edge theory. To be a world-class researcher in any subdiscipline today requires enormous commitment. A particle physics experiment might take a decade or more to conduct and involve many thousands of physicists, none of whom would have the time to explore other areas of physics, however motivated they might be. This problem is true for every subdiscipline of the field.

  Fermi was certainly the last man who knew everything about physics, the study of matter, energy, time, and their relationships—the way the physical world works. He knew everything about how the physical world worked across subdisciplines and across theory and experiment as far as physicists were able to know these things during his lifetime. Our knowledge has evolved since he died, shaped by theory and experiment in ways that would have delighted Fermi had he lived. Even so, for one person to master all the physics of his day was a unique achievement. We may never see another like him.

  ACKNOWLEDGMENTS

  This project has been one of the great adventures of my life and my wife, Susan, was by my side the whole way, as always. We traveled far and wide in search of Enrico Fermi and met an enormous number of people who have been incredibly helpful and generous. This is my opportunity to thank everyone. Please forgive me if I have omitted anyone inadvertently.

  My first thanks go to a group of people who worked with Fermi when they were young and who generously shared their memories of him. These include Geoffrey Chew, James Cronin, Jerome Friedman, Richard Garwin, Arthur Rosenfeld, Jack Steinberger, and Courtney Wright. Geoffrey Chew was the first to suggest the title of this book. Tsung-Dao Lee and Chen Ning Yang, colleagues of my father, were supportive and encouraging; many years ago, Lee posed the question that led to my father’s muon neutrino experiment. The support of these scientists for this project has been a special privilege and has brought my subject vividly to life. Sadly, James Cronin and Arthur Rosenfeld have since passed away.

  My archival research began at the University of Chicago’s Regenstein Library. I am grateful to Julia Gardner, Head of Reader Services, Special Collections Research Center; Eileen Ielmini, Assistant University Archivist; and their respective staffs who were all extremely helpful. Christine Colburn was also helpful in the photographic archives. Outside of Chicago, Roger Blomquist, Patricia Canaday, and David Hooper at Argonne National Lab were generous with their time. Lance Friedmann and Sari Gluckin were amazing hosts during our frequent visits to Chicago.

  Staff at the three major Manhattan Project sites were extremely helpful. I would like to thank Alan Carr, Rebecca Collinsworth, Barbara Lemmick, Heather McClenehan, and Glen McDuff in Los Alamos, Barbara Penland and Steven Stow in Oak Ridge, and Russel Fabre and the B-Reactor team in Hanford.

  At Columbia University, I am grateful to William Zajc, who sponsored me for a Visiting Scholar position, giving me crucial access to the university’s digital portal for scholarly resources for two years. Bill is a former colleague of my father who currently holds the I. I. Rabi Chair of Physics that my father held in the 1990s. Bill was a crucial sounding board and invaluable resource throughout this project, including last-minute comments that saved me from making several mistakes. I am grateful for the many hours spent with him. I am also grateful to Christopher Laico and Tom McCutchon, who provided special access to the Columbia University archives.

  In College Park, Maryland, I’d like to thank Greg Good, the director of the American Institute of Physics Center for the History of Physics, as well as the director of the AIP’s Neils Bohr Library, Melanie Mueller, and her colleagues Amanda Nelson and Audrey Lengel. Also in College Park, National Archives staff Rebecca Calcagno, Tab Lewis, and Laurel Macondray, were helpful.

  We spent one month in Rome during the fall of 2015 where I was a Visiting Scholar at the American Academy. Founded in 1894 and set in a magnificent villa atop Gianicolo Hill overlooking all of Rome, the Academy has been home to countless scholars, artists, writers, and musicians. Our apartment in the greenhouse at the Villa Aurelia was indeed a luxurious base camp. Thanks to the entire staff, including President Mark Robbins, Executive Director Kim Bowes, and community members Gianpaolo Battaglia, Christine Begley, Paola Gaetani, Denise Gavio, Lindsay Harris, Sebastian Hierl, Peter Miller, Laura Offeddu, Cristina Puglisi, and to everyone else who made our stay so pleasant and productive. We note with sadness the passing of Administrative Director Pina Pasquantonio, who was particularly helpful during our stay. We owe gastronomic thanks to Chris Behr and his team at the Rome Sustainable Food Project, founded by Alice Waters, with whom we enjoyed two memorable meals. I am also indebted to William Higgins, who first introduced me to the Academy, and to Eli Gotlieb, a former Rome Prize winner, who helped me with the application process.

  In Rome, many people gave their time and expertise to the project. Luisa Cifarelli, president of the Italian Physics Society, hosted us at the 2015 Enrico Fermi Award dinner. She moved mountains to get us a tour of the Via Panisperna site, which was in the midst of major construction in preparation for its reopening as a museum in 2018. Giovanni Battimelli opened the doors to the vast Amaldi archives at La Sapienza and gave us unrestricted access during our stay in Rome. He continued to answer questions long after we returned to the United States. Francesco Guerra and Nadia Robotti have also been invaluable resources. They spent a full day with us in Rome, discussing our project and presenting their own highly informed, and sometimes iconoclastic, perspectives on Fermi and his colleagues. They also continued to provide valuable insights during the period following our visit. We will never forget the spectacular Sardinian dinner to which they treated us at a restaurant near La Sapienza. Paola Cagiano and Alessandro Romanello served as helpful and generous guides through the archives of the Accademia dei Lincei and the Reale Accademia d’Italia. Alessandro also joined us for a wonderful lunch near the Villa Corsini, and then drove us back to the American Academy one afternoon in the pouring rain. Also in Rome, Laura Fermi’s nephew, Giorgio Capon, and his wife, Teresa, welcomed us into their home, the same home in which Laura grew up, and shared memories of Enrico and Laura. Others who were helpful along the way include Sandro Bettini, Mauro Canali, Adele La Rana, Giovanni Organtini, Marta Pepe, Francesca Salvatore, and Andrea Trentini.

  In Pisa, Roberto Vergara Caffarelli was extraordinarily generous with his time and insights and remained helpful throughout the project. Luca Galli and Giovanni Signorelli were brilliant archival and culinary guides; our morning caffé crema remains a fond memory. In addition, I would like to thank Maura Beghè, Monica Biondi, Alessandro Corsi, Chiara Letta, Anita D’Orazio, Umberto Parrini, and Maddalena Taglioli.

  In Geneva, we were welcomed by the physicists at CERN, who are in the midst of one of history’s greatest scientific odysseys. Director General Fabiola Gianotti took time out of a hectic schedule to chat about her own work and how it related to Fermi; she also arranged for Steven Goldfarb and Iva Raynova t
o give us a tour of the ATLAS experiment. We were joined in our meeting with Fabiola by Jack Steinberger, with whom we also enjoyed having lunch in the CERN cafeteria. Ugo Amaldi and his wife, Clelia, hosted us at their lovely home for a leisurely glass of wine and biscotti while he talked about his father, Edoardo, his mother, Genestra, and his own memories of the Fermi family. He independently suggested the title of this book. Toward the end of our visit with him, we were briefly joined by his daughter Silvia, a spitting image of her beautiful grandmother.

  Our time in England was quite productive. Our travels took us to the home of Fausta Segrè Walsby and her husband, Tony, in Bristol; to the home of Judd Fermi’s widow, Sarah Fermi, in Cambridge; and to the Senior Common Room at Exeter College, Oxford, where we met with physicist and writer Frank Close. We thoroughly enjoyed all of these meetings and appreciate their ongoing help. Many thanks to Elizabeth Greitzer and John Durrell with whom we stayed in London—we felt right at home and wish we could see them more often.

  Three professional physicists read the drafts carefully and helped me through the thickets of explaining complicated concepts in ways that the general public can understand and appreciate: William Zajc of Columbia University, mentioned above; Nicholas Hadley of the University of Maryland, an old high school friend who has played a major role in two significant particle discoveries during his career; and Andrea Gambassi of the International School for Advanced Studies (SISSA) in Trieste, who in addition to making some important scientific corrections was kind enough to explain the intricacies of a Scuola Normale Superiore education. All three are distinguished, busy scientists. They all read my drafts voluntarily and provided essential feedback on numerous aspects of the book. I hope they enjoyed reading it as much as I enjoyed discussing it with them. Any mistakes or errors in the physics are, of course, solely my own.