Enrico Fermi

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Enrico Fermi : biography

29 September 1901 – 28 November 1954

One of Fermi’s first sources for the study of physics was a book found at the local market of Campo de’ Fiori in Roma. The 900-page book, titled Elementorum physicae mathematicae, written in Latin by Jesuit Father Andrea Caraffa, a professor at the Collegio Romano, covered subjects like mathematics, classical mechanics, astronomy, optics, and acoustics to the extent that they were understood when it was written in 1840. Fermi befriended another scientifically inclined student named Enrico, Enrico Persico, and the two worked together on scientific projects such as building gyroscopes and measuring the Earth’s magnetic field. Fermi’s interest in physics was further encouraged by his father’s colleague Adolfo Amidei, who gave him several books on physics and mathematics, which he read and assimilated quickly.

Post-war work

After the war, Fermi served on the General Advisory Committee of the Atomic Energy Commission, a scientific committee chaired by Robert Oppenheimer that advised the commission on nuclear matters and policy. Following the detonation of the first Soviet fission bomb in August 1949, Fermi, along with Isidor Rabi, wrote a strongly worded report for the committee, opposing the development of a hydrogen bomb on moral and technical grounds. But Fermi also participated in work on the hydrogen bomb at Los Alamos as a consultant and, along with Stanislaw Ulam, calculated that the amount of tritium needed for Teller’s model of a thermonuclear weapon would be prohibitive, and a fusion reaction could not be assured to propagate even with this large quantity of tritium. Fermi was among the scientists who testified on Oppenheimer’s behalf at the Oppenheimer security hearing in 1954 that resulted in denial of Oppenheimer’s security clearance.

In his later years, Fermi continued teaching at the University of Chicago. His PhD students in the post-war period included Owen Chamberlain, Geoffrey Chew, Jerome Friedman, Marvin Goldberger, Tsung-Dao Lee, Arthur Rosenfeld and Sam Treiman. He also conducted important research in particle physics, especially related to pions and muons. In a paper co-authored with Chen Ning Yang, he speculated that pions might actually be composite particles. Fermi wrote a paper "On the Origin of Cosmic Radiation" in which he proposed that cosmic rays arose through material being accelerated by magnetic fields in interstellar space, which led to a difference of opinion with Teller. Fermi examined the issues surrounding magnetic fields in the arms of a spiral galaxy. He also mused about what is now referred to as the "Fermi Paradox": the contradiction between the presumed probability of the existence of extraterrestrial life and the fact that contact has not been made.

Toward the end of his life, Fermi questioned his faith in society at large to make wise choices about nuclear technology. He said:

Fermi died at age 53 of stomach cancer in his home in Chicago, and was interred at Oak Woods Cemetery.

Manhattan Project

Soon after his arrival in New York City on 2 January 1939, Fermi was offered five different chairs, and chose to work at Columbia University, where he had already given summer lectures in 1936. He ultimately became an American citizen in July 1944, the earliest date the law allowed. Soon after his arrival, he received the news that in December 1938, the German chemists Otto Hahn and Fritz Strassmann had detected the element barium after bombarding uranium with neutrons, which Lise Meitner and her nephew Otto Frisch correctly interpreted as the result of nuclear fission. The news of Meitner and Frisch’s interpretation of Hahn and Strassmann’s discovery crossed the Atlantic with Niels Bohr, who was to lecture at Princeton University. Isidor Isaac Rabi and Willis Lamb, two Columbia University physicists working at Princeton, found out about it and carried it back to Columbia. Rabi said he told Enrico Fermi, but Fermi later gave the credit to Lamb:

Bohr soon thereafter went to Columbia to see Fermi. Not finding Fermi in his office, Bohr went down to the cyclotron area and found Herbert L. Anderson. Bohr grabbed him by the shoulder and said: "Young man, let me explain to you about something new and exciting in physics." For Fermi, the news came as a profound embarrassment, as the transuranic elements that he had partly been awarded the Nobel Prize for discovering were likely to turn out to be fission products. He added a footnote to his as yet unpublished Nobel Prize acceptance speech to this effect.