Ugo Fano, professor emeritus of physics at the University of Chicago and a leader in theoretical atomic physics, died in Chicago on 13 February 2001 of complications from Alzheimer’s disease.
Born in Turin, Italy, on 28 July 1912, Ugo was the son of a mathematics professor. He grew up in Turin and Villa Fano, near Verona, an estate that his grandfather acquired and the family continues to enjoy. The atmosphere of his childhood was intensely intellectual. Being somewhat sickly, he was tutored until he entered the fourth grade. From the time he received his first bicycle at age 12, he developed a love for the outdoors and for mountains—first hiking and then rock climbing, especially in the Dolomites.
While hiking in the summer of 1924, Ugo’s father exchanged a few words with a group of young scientists from Rome. He later told Ugo that one of those scientists would go far—a man named Enrico Fermi, who would eventually become Ugo’s mentor.
Ugo’s school friends included Salvatore Luria. Ugo’s older cousin Giulio Racah persuaded Ugo to study physics with Enrico Persico, who had moved to the University of Turin. In 1934, after Ugo had completed his doctorate in physics at the University of Turin in 17 months, Persico arranged for him to join Fermi’s group in Rome.
With scientific excitement and great humor, Fermi led the group to explore new directions and then challenge each new idea until it was demonstrably sound. Fermi would test ideas for himself, but saw that each of the younger scientists went through the same process. One story Ugo enjoyed telling concerns work on interpreting strange-seeming shapes of spectral absorption lines. Ugo worked several weeks on the problem, discussing it with Fermi as he progressed. One day he suggested an approach to Fermi, who, the next day, put his head into Ugo’s office and said, “Fano, you were right.” Weeks later, with a satisfactory solution, Ugo proposed a joint paper, but Fermi said, “No, the usual acknowledgment would be fine.” Not long after the paper appeared under Ugo’s name alone, Ugo peeked into Fermi’s notebook and found that Fermi had worked out the solution—in precisely the notation that had appeared in the published paper—the same day he told Ugo he was right.
In 1935, while a lecturer at the University of Rome, Ugo visited Göttingen, Germany, and Copenhagen, Denmark, and met Arnold Sommerfeld, Niels Bohr, Edward Teller, George Gamow, and other established scientists. Two years later, he moved to Leipzig, Germany, to work with Werner Heisenberg. There he interpreted nuclear quadrupoles by modeling nuclei as aggregates of alpha particles, as Teller and John Wheeler did at about the same time. Then, a seminar in Rome by Pascual Jordan in 1938 stimulated his interest in radiation biology and genetics, which would become central topics for his later research.
In 1935, Ugo left Italy, where the ethnic laws had made it impossible for him to work. First he went to Paris, where he collaborated with Pierre Joliot. Then he arrived in the US in 1939. He became a guest researcher at the Carnegie Institution of Washington (CIW). He received his first research position at CIW at Cold Spring Harbor in New York, but World War II intervened, so he began work on ballistics at the US Army’s Aberdeen Proving Ground in Aberdeen, Maryland.
After the war, he returned to CIW at Cold Spring Harbor, but actually spent much time at the physics department of Columbia University, where he started his exploration of the effects of radiation on matter. At Cold Spring Harbor, Ugo studied the biological effects of radiation on living organisms. During his early work with Drosophila and genetic resistance to radiation effects, and his later work at the National Bureau of Standards (NBS), he set himself to the task of sorting out the complex array of processes that radiation could induce in living systems.
In 1946, Ugo joined the group of Lauriston Taylor at the NBS, where he elucidated fundamental physical processes. He worked closely with experimentalists such as Robert Madden and Keith Codling to use synchrotron radiation to study spectra in regions previously almost inaccessible, and then, with theorists around him, to interpret those results. One notable example concerned the excitation of quasi-bound states buried in continua, whose spectra, with their Fano line shapes, imply much about the nature of electron correlation.
In 1966, with the NBS’s impending move to Gaithersburg, Maryland, Ugo’s old friend Robert Platzman and the chair of the University of Chicago physics department, Mark Inghram, persuaded him to join the physics faculty at Chicago. There, Ugo developed a lively group of graduate students and postdoctoral associates, many of whom are now spread throughout academia, government, and industry, continuing research in the tradition they learned from him. Ugo continued, uninterrupted, his research on the interaction of radiation and matter well past his retirement in 1982 and into the late 1990s.
Ugo was always very matter-of-fact, questioning every new scientific hypothesis and model with a candor characteristic of a true scholar. He emphasized the importance of working on problems that appeared solvable in the sense of finding an effective way to connect what one knew with something yet to be found. He was skeptical of efforts to solve “fundamental” or what he considered “philosophical” problems in physics, not because he thought these were unimportant. On the contrary, he thought that current theory could only be a partial, incomplete description of physics. In his humility, he believed that people capable of truly contributing to those problems are so rare that nobody he knew should bother to try.
Ugo received the Enrico Fermi Award from the US Department of Energy in 1995. The special issue of Physics Essays (June and September 2000) honors Ugo. It contains his curriculum vitae, a bibliography, a biographical essay, and 40 articles on recent developments in topics he studied. The issue also carries his last article, “Memories of an Atomic Physicist: For My Children and Grandchildren.”
