Jewish Scientists Helped America Build the Atom Bomb

J. Robert Oppenheimer is probably the best-known Jewish scientist born in the US who worked at the Manhattan Project (MP), the program that produced the atom bombs dropped on Hiroshima and Nagasaki in August 1945. Were there other US-born Jewish scientists at MP? If so, who were they and what did they contribute?

Edward Teller is probably the best-known Jewish scientist at MP not born in the US, who later also worked on the hydrogen bomb. Were there other foreign-born Jewish scientists at MP? If so, who were they and what did they contribute?

The 26 biographical sketches presented below make a (belated) start at answering these questions. I realize the lists are not exhaustive. Comprehensive coverage would require book-length treatment, which I’m hoping someone else will undertake.

US-Born Jewish Scientists at MP

J. Robert Oppenheimer: Scientific director of the Los Alamos Laboratory. Without his decisive, inspirational and in many ways fearless leadership, the atomic bomb probably would not have been built in time to be useful. His gravitas comes through in a 1965 interview. For an assessment of Oppenheimer by the MP Director, General Leslie M. Groves, see [2: 63]. See also the Bird and Sherwin biography of Oppenheimer [4].

Richard P. Feynman: Nobel Prize in physics, 1965. At Los Alamos, Feynman was assigned to the theoretical division of Hans Bethe. He and Bethe developed the Bethe–Feynman formula for calculating the yield of a fission bomb, which built upon previous work by Robert Serber. Oppenheimer sent Feynman to Tennessee to identify safety problems at the Oak Ridge uranium separation plant (Y-12) and suggest solutions, which were adopted. “The plant would have blown up if nobody had paid attention,” Feynman commented [6: 124].

Robert Serber: A former student of Oppenheimer, Serber was one of the first scientists to arrive at Los Alamos. He produced the “Los Alamos Primer," which explained the physics and goals of MP to all incoming scientific staff. According to Hans Bethe [1: 417] “The theory of the fission bomb was well taken care of by Serber and two of his young people.” Serber gave “Fat Man” and “Little Boy” their names. He was present at the Trinity Test in July 1945 and was part of the American team that entered Hiroshima to measure radiation levels and assess damage. More on Serber here.

Stanley P. Frankel: Frankel determined that a uranium fission chain reaction would release considerable energy in a very large explosion and made the first calculations to determine the amount of uranium needed for a fission bomb. Frankel also performed other calculations on ENIAC, the world’s first electronic computer, which laid the computational groundwork for developing thermonuclear weapons. More on Frankel here.

Isadore Perlman: Perlman joined Glenn Seaborg's group at MP, which was developing chemical methods for separating plutonium from uranium and fission products. During 1942-1945, Perlman was deputy director of the Plutonium Chemistry Section at Met Lab, then director of the Plutonium Chemistry Section at Oak Ridge, and served in a key role in the production plant at Hanford, Washington. An article on Perlman by Glenn Seaborg is available here.

Alvin M. Weinberg: At Met Lab, Weinberg worked closely with Enrico Fermi and others to develop the world's first nuclear reactor. While there, he worked with Eugene Wigner on neutron multiplication. He also worked at the Oak Ridge Nuclear Laboratory (ORNL). According to Wigner [see 3], Weinberg “designed almost alone the Oak Ridge pilot reactor.” Weinberg served as director of ORNL between 1955 and 1973. More here.

David Bohm: A student of Oppenheimer at Berkeley, Bohm performed calculations for the calutrons at the Y-12 Oak Ridge plant used to electromagnetically enrich uranium. Bohm later authored several physics books and also one on how the human brain works, Thought as a System. See the Peat biography on Bohm [11] and [4].

Phillip Morrison: At Met Lab, Morrison worked with Eugene Wigner on the design of nuclear reactors. In 1944, moved to Los Alamos where he worked on the development of explosive lenses required to detonate the implosion-type nuclear weapon. He transported the core of the Trinity test device to the test site and was present at the test. He traveled to Tinian to assemble the bomb that was dropped on Hiroshima and accompanied Serber to Hiroshima to assess damage. More in [4] and here.

Frank Oppenheimer: Brother of J. Robert Oppenheimer. In 1941, Frank Oppenheimer was a group leader in uranium isotope separation under Lawrence at the University of California Radiation Laboratory. His brother Robert then asked him to conduct research for MP, going to Oak Ridge to monitor equipment at the Y-12 plant and then moving to Los Alamos, where he worked on planning and conducting the Trinity Test in July 1945. More here.

Aaron Novick: A physical chemist, Novick worked at various sites associated with MP, including Met Lab, the plutonium production plant at Hanford, and Los Alamos. He witnessed the Trinity Test. More here.

Arnold Kramish: While still in college, Kramish worked in the special engineering division at ORNL, Los Alamos, and at the Philadelphia Navy Yard. At Philadelphia, he was seriously injured when uranium enrichment equipment exploded. He would not accept last rites from a priest because he was Jewish and credited his mother for saving his life by feeding him chicken soup! During the 1980s, Kramisch served as chair of a study for the Reagan Administration that recommended pursuing the development of the Strategic Defense Initiative. More here.

Arthur Levy: At MP, Levy was part of team that developed high explosive casting procedures for the “Fat Man” bomb. After the war, he worked for NASA's predecessor, the National Advisory Committee on Aeronautics, for the Brookhaven National Laboratory, and for the Battelle Memorial Institute. More here.

Paul Olum: Olum worked on the scientific staff at Los Alamos as a theoretical physicist. He was close friends with Feynman, with whom he shared an office. After WWII, he spent a postdoctoral year at the Institute for Advanced Study, Princeton. He was President of the University of Oregon, 1980-89. More here.

Foreign-Born Jewish Scientists at MP

Edward Teller: Teller was an early member of MP at Los Alamos and later became known as “the father of the hydrogen bomb.” An interview is available here. He co-founded the Lawrence-Livermore National Laboratory with MP colleague Ernest Lawrence.

John von Neumann: Contributions to MP included the concept and design of explosive lenses used in the implosion bomb as well as carrying out thousands of calculations, a human “computing machine” that astonished colleagues. One key calculation he made at Oppenheimer’s request, determined that implosion was theoretically possible. More here

Eugene P. Wigner: Nobel Prize in physics, 1963. Wigner was present when Chicago Pile-1 went critical on December 2, 1942 at Met Lab. He continued working there through 1945. Wigner made a famous comment [5: 92] on the slow going in the early stages of MP: “We often felt as though we were swimming in syrup.” An interview is available here.

Leo Szilard: In 1939, Szilard authored the letter to FDR signed by Albert Einstein that launched MP. He worked with Fermi at the University of Chicago to build a uranium and graphite atomic pile in which the first self-sustaining nuclear chain reaction was achieved in 1942. More here.

Stanislaw M. Ulam: A mathematician, Ulam was a member of Hans Bethe’s theoretical division at Los Alamos, working on hydrodynamic calculations to predict the behavior of explosive lenses needed in an implosion-type weapon. He later originated the Teller–Ulam design of thermonuclear weapons (the hydrogen bomb). More here.

Isidor I. Rabi: Nobel Prize in physics, 1944. He was a consultant at Los Alamos and was present at the Trinity Test. Rabi later discovered nuclear magnetic resonance, used in magnetic resonance imaging (MRI), a diagnostic tool in medicine. See also this, and the Rigden biography [10].

Emilio G. Segrè: Nobel Prize in physics, 1959. He came to the US in 1938 because of Mussolini’s Racial Laws. He helped discover the isotope plutonium-239, used to make the “Fat Man” atomic bomb dropped on Nagasaki. An interview is available here.

James Franck: Nobel Prize in physics, 1925. Franck was forced by Nazi racial laws to leave Germany in 1933, coming to the US. At MP, he served as Director of the Chemistry Division of the Chicago Met Lab.  At Göttingen, Frank supervised Robert Oppenheimer’s Ph.D. thesis defense. More here.

Felix Bloch: Nobel Prize in physics, 1952. He came to the US in 1933 after the Nazi racial laws were passed, joining Stanford University where he became its first professor of theoretical physics. At MP, he made the first experimental determination of the energy distribution of neutrons from fission. He worked under Hans Bethe at Los Alamos. More here.

Rudolf E. Peierls: In March 1940, he co-authored the Frisch–Peierls memorandum showing that an atomic bomb could be made from about one kilogram of fissionable uranium-235, a significantly smaller amount than believed at the time. These findings influenced the development of MP. He worked at MP as part of the British Mission. More here.

Otto R. Frisch: He collaborated with Peierls on the Frisch–Peierls memorandum and worked at MP as part of the British Mission. His aunt Lise Meitner was on the team that discovered nuclear fission. Only her colleague Otto Hahn received the Nobel Prize in chemistry in 1944, an infamous Nobel Prize snub. Meitner refused to work at MP, stating “I will have nothing to do with a bomb!" [8: 305]. More on Frisch here.

Samuel A. Goudsmit: At MP, he was the scientific head of a team tasked with assessing the progress of the Nazi atomic bomb project. While in Europe, he traveled to his childhood home in The Hague and found out that his parents died during the Holocaust. Goudsmit concluded that the failure of the German atomic bomb project was attributable to factors such as bureaucracy, Allied bombing campaigns, the persecution of Jewish scientists, and Werner Karl Heisenberg's failed leadership. See Goudmit’s book [9].

Victor F. Weisskopf: At Los Alamos, he was associate head of the Theoretical Division under Hans Bethe. During 1961-1966 was director-general of CERN, the European Organization for Nuclear Research. In 1975, he was appointed by Pope Paul VI to the 70-member Pontifical Academy of Sciences. More here.

 “Yes, But …”

MP secrets were passed to the Soviet Union by Julius Rosenberg and his wife Ethel, Ethel’s brother David Greenglass (who worked at MP), Harry Gold, Morton Sobell, and Ted Hall (who also worked at MP) -- as well as Klaus Fuchs, a German scientist who worked at MP as part of the British Mission but was not Jewish. What about this?

  • Trying to diminish the contributions of the Jewish scientists who helped America end the war with Japan by insinuating a “link” on religious or racial grounds with criminals like the Rosenbergs is anti-Semitic prejudice. Put it this way: It would be just as absurd and irresponsible to claim that Italians must belong to the Mafia because they are Italian; or that the Mafia was at MP because Enrico Fermi, Emilio Segrè and Bruno Rossi were Italian and worked there.
  • In a formal memo to the Manhattan District Engineer [2: 63], General Groves ordered that Robert Oppenheimer be granted security clearances “without delay, irrespective of the information which you have concerning Mr. Oppenheimer.” Though Oppenheimer’s past communist associations were well known, Groves wrote [2: 63] “I would be greatly surprised if Oppenheimer had ever consciously committed a disloyal against the United States.” In fact, Oppenheimer had several persons removed from MP because of their Soviet sympathies [see 7].
  • Jewish conspiracy nuts, ready at the slightest opportunity to paint all Jews with the same anti-Semitic brush, nevertheless insist on political correctness when it comes to linking Islam with terrorism. They might grant that all or most terrorists in recent times have been Muslims, but warn we must be careful not to label all Muslims terrorists or associate Islam itself with terrorism. When it comes to Jews (or Judaism), however, these distinctions do not apply, according to these wackos.


[1] Richard Rhodes, The Making of the Atomic Bomb (Simon & Schuster, 1986).

[2] Leslie R. Groves, Now It Can Be Told: The Story Of The Manhattan Project (Da Capo Press, 1983).

[3] S. L. Sanger, Working on the Bomb: An Oral History of WWII Hanford (Portland State University, 1995.

[4] Kai Bird and Martin J. Sherwin, American Prometheus: The Triumph and Tragedy of J. Robert Oppenheimer (Vintage Books, 2006).

[5] Cynthia C. Kelly (ed.), The Manhattan Project: The Birth of the Atomic Bomb in the Words of Its Creators, Eyewitnesses, and Historians (Black Dog & Leventhal Publishers, 2009).

[6] Steve Sheinkin, Bomb: The Race to Build--and Steal--the World's Most Dangerous Weapon (Flash Point, 2012).

[7] John Earl Haynes, Early Cold War Spies: The Espionage Trials that Shaped American Politics (Cambridge University Press, 2006).

[8] Ruth Lewin Sime, Lise Meitner: A Life in Physics (University of California Press, 1996).

[9] Samuel A. Goudsmit, Alsos (American Institute of Physics; 1985).

[10] John S. Rigden, Rabi: Scientist and Citizen (Harvard University Press, 2000).

[11] F. David Peat, Infinite Potential: The Life and Times of David Bohm (Addison-Wesley, 1996).