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Leo Szilard - A Biographical Chronology

Leo Szilard, 1926 photo. Courtesy Szilard Papers, UCSD; used by permission. Contact Mandeville Special Collections Library, U.C. San Diego, for information on obtaining Szilard images.

Leo Szilard: Physicist, Molecular Biologist.
Born Budapest, Hungary, February 11, 1898.
Died La Jolla, California, U.S.A. May 30, 1964.

1898 Born February 11 in Budapest, Austro-Hungary, the son of a civil engineer.

1908 Student at Reáliskola, Budapest District VI, until graduation in 1916.

1916 Enrolled as engineering student at Budapest Technical University.

1917 Entered Austro-Hungarian Army as officer-candidate, artillery.

1918 Spared from probable death at battle front by chance illness. Honorably discharged from Austro-Hungarian army at end of WWI.

1919 Resumed engineering studies at Budapest Technical University. Left Hungary to escape repressive and anti-Semitic Horthy regime.

1920 Arrived in Berlin. Continued engineering studies at Technische Hochschule (Institute of Technology) in Berlin-Charlottenburg, then enrolled as physics student at University of Berlin.

1921 Took physics classes from Einstein, Planck, and von Laue.

1922 Independent dissertation on phenomenological thermodynamics praised by Einstein and awarded the notation "eximia," the highest honor. Received doctorate in physics from University of Berlin.

1923 Collaborated with Hermann Mark on x-ray diffraction experiments at Kaiser-Wilhelm Institutes for Chemistry, Berlin-Dahlem.

1924 Began 3-year appointment as Assistant to Nobel Laureate Max von Laue at the University of Berlin's Institute for Theoretical Physics.

1926 Began 7-year collaboration with Albert Einstein on the invention of home refrigerators without moving parts. Their joint inventions would include the annular linear induction pump, or Einstein-Szilard pump.

1927 Appointed Privatdozent (instructor) in Physics at University of Berlin.

1928 Began teaching seminars on quantum theory with John von Neumann. Hired as consultant by German General Electric Company (A.E.G.) to develop Einstein-Szilard refrigerator. Filed German patent application on the linear accelerator.

1929 Filed German patent application on the cyclotron. Met H.G. Wells. Published, in Zeitschrift für Physik, his classic analysis of Maxwell's Demon, in which he showed that the entropy of a unit of information was equal to k ln 2.

1930 Met future wife Gertrude (Trude) Weiss. Attempted to organize an international movement of progressive intellectuals based on H.G. Wells' Open Conspiracy. Taught theoretical physics seminar with Erwin Schrödinger and John von Neumann. Taught seminar on nuclear physics and chemistry with Lise Meitner.

1931 Filed German patent application on the electron microscope. Prototype refrigerator using Einstein-Szilard pump successfully operated in A.E.G. Research Institute.

1932 During a visit to the United States, attempted to organize a scientific boycott of Japan to protest Japanese aggression in China. Development of Einstein-Szilard refrigerator abandoned due to invention of Freon and increasing economic Depression.

1933 Fled Germany March 31 to escape Nazi persecution. In Britain, aided fellow refugees and catalyzed the formation of the Academic Assistance Council. Ernest Rutherford quoted in London Times on September 12 as saying "anyone who looked for a source of power in the transformation of the atoms was talking moonshine." While walking through the streets of central London after reading this article -- as he waited for a streetlight at the corner of Southampton Row -- Leo Szilard conceived the neutron chain reaction.

1934 On March 12, filed first British patent application on the neutron chain reaction. Request for laboratory space at Cambridge to investigate chain reactions rejected by Ernest Rutherford. Began experiments at London's St. Bartholomew's Hospital in search of a chain-reacting element, for which he suspected beryllium. Invented the Szilard-Chalmers reaction, a method for concentrating artificially produced radioactive isotopes.

1935 Received a refugee fellowship and continued his research in nuclear physics at the Clarendon Laboratory, Oxford. Concentrated on indium, which demonstrated puzzling isotopic activity.

1936 Assigned chain-reaction patent to British Admiralty to ensure patent would remain secret. Unsuccessfully attempted to convince colleagues, including Niels Bohr and Enrico Fermi, that atomic energy might be feasible, and if feasible was potentially so dangerous that research should be controlled.

1937 Continued research in nuclear physics at Oxford. Designed a betatron, in collaboration with James Tuck.

1938 Moved to New York City, in anticipation of outbreak of World War II. Concluded, after further experiments, that indium was incapable of chain-reacting.

1939 Predicted, immediately on learning of discovery of fission, that uranium might sustain a chain reaction. Began experiments at Columbia University, in collaboration with Walter Zinn, and demonstrated that neutrons were emitted in fission. Unsuccessfully proposed that results of fission experiments be kept secret because of danger of a German atomic bomb. Collaborated with Enrico Fermi on experiment testing uranium-water system. Proposed uranium-carbon lattice design for nuclear reactor. Unsuccessfully attempted to convince Fermi of likelihood of chain reaction and need to continue experiments. Visited Albert Einstein with Eugene Wigner (and later with Edward Teller) to discuss methods of averting German atomic bomb. Drafted, from Einstein's dictation, Einstein's August 2 letter to President Franklin D. Roosevelt.

1940 Received only $6,000 in research funds from government. With Enrico Fermi and Herbert Anderson, performed small-scale experiment with carbon demonstrating that uranium-carbon system might sustain a chain reaction. After German invasion of France, proposal for secrecy finally generally accepted by fellow scientists. In November, with Enrico Fermi, finally employed on government defense contract.

1941 With minimal government support, personally arranged for the industrial production of pure graphite and uranium necessary for a reactor.

1942 Moved to Chicago to begin employment at University of Chicago "Metallurgical Laboratory." Continued procuring pure graphite and uranium and designed reactor cooling systems. Declared by General Groves, head of newly-formed Manhattan Project, to be detriment to project who should be arrested and interned for duration of war. Witnessed successful demonstration of first nuclear chain reaction December 2.

1943 Advised colleagues on all aspects of reactor design. Correctly predicted that atoms dislocated by radiation damage ("Wigner disease") could release stored energy exothermically (the "Szilard complication"). (Effect caused 1957 Windscale nuclear accident in Britain.) Forced, by General Groves, to sell his atomic energy patent rights to the U.S. government.

1944 Proposed term "breeder" to describe reactor able to generate more fuel than it consumed. Became increasingly concerned about potential for post-war nuclear arms race.

1945 Unsuccessfully sought personal meetings with President Roosevelt, then Truman. Met with Secretary-of-State-designate James Byrnes. Co-authored Franck Report. Circulated petition among Project scientists opposing use of bomb on moral grounds. After end of war, organized successful opposition to May-Johnson bill, which placed atomic energy under military control. Testified before U.S. Senate committee on the implications of atomic energy.

1946 Founded, with Albert Einstein and others, the Emergency Committee of Atomic Scientists. Appointed Professor of Biophysics at the Institute of Radiobiology and Biophysics, University of Chicago.

1947 Decided to leave physics for biology. Attended Max Delbrück's "Phage Course" at Cold Spring Harbor, New York. "Letter To Stalin," proposing methods for reducing US-USSR tensions, published in Bulletin of the Atomic Scientists.

1948 Started own laboratory, with Aaron Novick, at University of Chicago, and began research in molecular biology. Invented the chemostat, an apparatus for continuous production of bacterial cultures under controlled conditions.

1949 Facilitated creation of "Midwestern Phage Group," with monthly meetings including Hershey, Lederberg, Luria, Watson, and others. Began publishing papers in biology.

1950 Publicly opposed development of Hydrogen bomb. Explained that such bombs could be coated with cobalt to increase radioactive fallout. With Aaron Novick, published "Experiments with the chemostat on spontaneous mutations of bacteria."

1951 Married his long-time friend Gertrud (Trude) Weiss, a public-health physician. With Aaron Novick, published paper describing phenotypic mixing in phage.

1953 Closed his Chicago biology laboratory and became a "roving theoretical biologist." Began year as visiting professor at Brandeis University.

1954 With Aaron Novick, proposed negative feedback regulation of enzyme activity. Became a Fellow of the American Academy of Arts and Sciences.

1955 Joint patent on nuclear reactor, with Enrico Fermi, issued by U.S. Patent Office.

1956 Became Professor of Biophysics at Enrico Fermi Institute for Nuclear Studies, University of Chicago.

1957 Began participation in "Pugwash" conferences, established to allow eminent scientists from East and West to discuss peace and world security. Attended first "Pugwash" conference in Pugwash, Nova Scotia. Offered Directorship of new Institute for Nuclear Physics in Berlin, but declined. Proposed to Jacques Monod that enzyme induction could be due to an anti-repressor.

1958 Attended second and third Pugwash conferences in Canada and Austria.

1959 Published theory of aging. Diagnosis of bladder cancer. Rejected standard treatment and designed his own radiation therapy.

1960 Underwent self-designed radiation therapy at Memorial Hospital, New York City. Cured of cancer. Atoms for Peace Award. Personal meeting with Soviet Premier Nikita Khrushchev, during Khrushchev's visit to New York, to propose methods of reducing US-USSR tensions, including Washington-Moscow "hotline. "

1961 Moved to Washington D.C. to seek "market for wisdom" in new Kennedy Administration. Elected to membership in National Academy of Sciences. Published short-story collection The Voice of the Dolphins. Honorary Doctor of Humane Letters, Brandeis University. Concluded that American government was incapable of change. Began national speaking tour "Are We On the Road to War?"

1962 Founded Council for Abolishing War (later renamed Council for a Livable World). Flew to Switzerland during Cuban Missile Crisis and attempted to avert World War III through personal diplomacy. In 1962 elections, Council support influenced outcome of close races, electing Senator George McGovern and others.

1963 Became Non-Resident Fellow of Salk Institute, La Jolla, California.

1964 Became a Resident Fellow of the Salk Institute. Completed paper on molecular basis of memory, "On Memory and Recall." Died in his sleep of a heart attack in La Jolla, California on May 30 at the age of 66.

Copyright 1995 - 1998 Gene Dannen

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Last modified: July 26, 1998
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