Klaus Fuchs

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Klaus Fuchs' ID badge at Los Alamos.
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Klaus Fuchs' ID badge at Los Alamos.

Emil Julius Klaus Fuchs (December 29, 1911 – January 28, 1988) was a German-born theoretical physicist and atomic spy who was convicted of surreptitiously supplying information on the British and American atomic bomb research to the USSR during, and shortly after, World War II. Fuchs was highly technically competent, being responsible for many significant theoretical calculations relating to the first fission weapons and early models of the hydrogen bomb while a physicist at Los Alamos National Laboratory.

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[edit] Early life

Klaus Fuchs was born in Rüsselsheim, Germany, the third of four children to Lutheran pastor Emil Fuchs and his wife Else Wagner. Fuchs' father was later a professor of theology at Leipzig University, while his grandmother, mother, and one sister eventually committed suicide. Fuchs' other sister was diagnosed as schizophrenic.

Fuchs attended university at both Leipzig University and Kiel University, and while at the latter he became active in politics and joined the Social Democratic Party of Germany and, in 1932, the Communist Party of Germany. In 1933, after an encounter with the recently-installed Nazis, he fled to France and after that was able to use family connections to flee to Bristol, England. He earned his PhD in Physics from the University of Bristol in 1937, studying under Nevill Mott, and took a DSc at the University of Edinburgh while studying under Max Born. A paper of his on quantum mechanics appeared in the Proceedings of the Royal Society in 1936, which contributed to his getting a teaching position at Edinburgh in 1937.

[edit] Wartime work and espionage

At the outbreak of war, German citizens in Britain were interned, and Fuchs was put into camps on the Isle of Man and later in Quebec, Canada, from June to December 1940. However, Professor Born intervened on Fuchs' behalf. By early 1941, Fuchs had returned to Edinburgh, where he was approached by Rudolf Peierls to work on the "Tube Alloys" program — the British atomic bomb research project. A London GRU message of 10 August 1941 is a reference to the GRU reestablishing contact with Fuchs. Despite wartime restrictions, he was granted British citizenship in 1942 and signed the Official Secrets Act. After Nazi Germany invaded the Soviet Union in 1941, he would later testify, he began to transmit military secrets to the USSR, believing that the Soviets had a right to know what the United Kingdom (and later the United States) were working on in secret. (The exact dates on when he began passing information is somewhat inconsistent in the literature on the subject.) He testified that he had contacted a former friend in the German Communist Party, who put him in touch with someone at the Soviet embassy in Britain. His code-name was Rest.

In late 1943 Fuchs transferred along with Peierls to Columbia University, New York City to work on the Manhattan Project. Although Fuchs was an asset of GRU in Britain, his control was transferred to the NKGB when he moved to New York. From August 1944 Fuchs worked in the Theoretical Physics Division at Los Alamos, New Mexico under Hans Bethe. His chief area of expertise was the problem of imploding the fissionable core of the plutonium bomb, and was at one point given calculation work that Edward Teller had refused to do due to lack of interest. He was the author of techniques (such as the still-used Fuchs-Nordheim method) for calculating the energy of a fissile assembly which goes highly prompt-critical. Later, he also filed a patent with John Von Neumann, describing a method to initiate fusion in a thermonuclear weapon with an implosion trigger. He was one of the many Los Alamos scientists present at the Trinity test. While at Los Alamos, Fuchs loaned his automobile on a number of occasions to Richard Feynman, who used the vehicle to visit his dying first wife in a tuberculosis sanatorium in Albuquerque, New Mexico.

From the fall of 1947 to May of 1949, Fuchs gave to Alexandre Feklisov, his case officer, the principal theoretical outline for creating a hydrogen bomb and initial drafts for its development, at the stage they were being worked on in England and America in 1948. Fuchs provided the results of the test at Eniwetok atoll of uranium and plutonium bombs. Fuchs met with Feklisov six times. Fuchs provided key data on production of uranium 235. Fuchs revealed that American production was one hundred kilograms of U-235 a month and twenty kilos of plutonium per month. From this the Soviet Union could calculate the number of atomic bombs possessed by the United States, and concluded the United States was not prepared for a nuclear war at the end of the 1940s or even into the early 1950s. The information Fuchs gave Soviet intelligence in 1948 coincided with Donald Maclean's reports from Washington. The Soviet Union knew the United States did not have enough nuclear weapons to deal with both the Berlin blockade and the victory of the Communists in China at the same time.

Fuchs later testified that he passed detailed information on the project to the Soviet Union through a courier, Harry Gold (whom he knew as "Raymond"), in 1945 and further information about the hydrogen bomb in 1946 and 1947. Fuchs attended a conference of the Combined Policy Committee (CPC) in 1947, a committee created to facilitate exchange of atomic secrets between the highest levels of government of the U.S., Great Britain and Canada; Donald Maclean, as British co-secretary of CPC, was also in attendance. In 1946 when Fuchs returned to England and the Harwell Atomic Energy Research Establishment, he was confronted by intelligence officers as a result of the cracking of Soviet ciphers known as the VENONA project. Under prolonged interrogation by MI-5 officer William Skardon, Fuchs confessed in January 1950. Fuchs told interrogators the KGB acquired an agent in Berkeley, California who informed the Soviet Union about electromagnetic separation research of uranium-235 in 1942 or earlier. He was prosecuted by Sir Hartley Shawcross and was convicted on March 1, 1950. He was sentenced the next day to fourteen years in prison, the maximum possible for passing military secrets to a friendly nation. A week after the verdict, on March 7, the Soviet Union issued a terse statement denying that Fuchs served as a Soviet spy.

Fuchs' statements to British and American intelligence agencies was used to implicate Harry Gold, a key witness in the trials of David Greenglass and Julius and Ethel Rosenberg in the USA.

[edit] Value of Fuchs' data to the Soviet project

As a result of Fuchs' information, the first Soviet bomb, RDS-1 (above) closely resembled, even in its external shape, the U.S.-developed Fat Man bomb.
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As a result of Fuchs' information, the first Soviet bomb, RDS-1 (above) closely resembled, even in its external shape, the U.S.-developed Fat Man bomb.

Hans Bethe once said that Klaus Fuchs was the only physicist he knew who truly changed history. Because of the manner in which the head of the Soviet project, Lavrenty Beria, used foreign intelligence (as a third-party check, rather than giving it directly to the scientists, as he did not trust the information by default) it is unknown whether Fuchs' fission information had a substantial impact (and considering that the pace of the Soviet program was set primarily by the amount of uranium they could procure, it is hard for scholars to accurately judge how much time this saved the Soviets). Some former Soviet scientists said they were actually hampered by Fuchs' data, because Beria insisted that their first bomb ("Joe 1") should resemble the American plutonium bomb ("Fat Man") as much as possible, even though the scientists had discovered a number of improvements and different designs for a more efficient weapon.

Whether the information Fuchs passed relating to the hydrogen bomb would have been useful is still somewhat in debate. Most scholars have agreed with the assessment made by Hans Bethe in 1952, which concluded that by the time Fuchs left the thermonuclear program — the summer of 1946 — there was too little known about the mechanism of the hydrogen bomb for his information to be of any necessary use to the Soviet Union (the successful Teller-Ulam design was not discovered until 1951). Soviet physicists would later note that they could see as well as the Americans eventually did that the early designs by Fuchs and Edward Teller were useless. However, later archival work by the Soviet physicist German Goncharov has suggested that while Fuchs' early work (most of which is still classified in the United States, but copies of which were available to the Soviets) did not aid the Americans in their effort towards the hydrogen bomb, it was actually far closer to the final correct solution than was recognized at the time, and indeed spurred Soviet research into useful problems which eventually resulted in the correct answer. Since most of Fuchs' work on the bomb, including a 1946 patent on a particular model for the weapon, are still classified in the United States, it has been difficult for scholars to fully assess these conclusions. In any case, it seems clear that Fuchs could not have just given the Soviets the "secret" to the hydrogen bomb, since he did not himself actually know it.

[edit] Later life

After confessing, Fuchs was sentenced to fourteen years' imprisonment, and stripped of his British citizenship in December 1950. (Some claim that his confession was made to avoid the death penalty. However, according to at least one of his interrogators, he was actually labouring under the impression he would be allowed back to work at Harwell). He was released on June 23, 1959, after serving nine years and four months of his sentence at Wakefield prison. He was allowed to emigrate to Dresden, then in the German Democratic Republic (East Germany). He left Britain almost immediately and lived in Dresden with his father and a nephew.

In 1959, he married a friend of his from his years as a student Communist, Margarete Keilson. In East Germany, he continued his scientific career and achieved considerable prominence. He was elected to the Academy of Sciences and the Communist Party central committee, and was later appointed deputy director of the Institute for Nuclear Research in Rossendorf, where he served until he retired in 1979. He received the Order of Merit of the Fatherland and the Order of Karl Marx. He died near Dresden in 1988.

[edit] See also

  • Theodore Hall (another atomic spy at Los Alamos, though he and Fuchs were not aware of each other at the time)
  • Atom Spies

[edit] References

  • Ronald Friedmann: Klaus Fuchs. Der Mann, der kein Spion war. Das Leben des Kommunisten und Wissenschaftlers Klaus Fuchs, 2006, ISBN 3-938686-44-8
  • Hans Bethe, "Memorandum on the History of the Thermonuclear Program" (28 May 1952).[1]
  • Rodney P. Carlisle, "Fuchs, Klaus Emil Julius", American National Biography Online Feb. 2000, accessed 24 September 2005.
  • Mary Flowers, "Fuchs, (Emil Julius) Klaus (1911–1988)", rev., Oxford Dictionary of National Biography, Oxford University Press, 2004, [2], accessed 24 September 2005. (requires library access)
  • German A. Goncharov, "American and Soviet H-bomb development programmes: historical background," Physics - Uspekhi 39:10 (1996): 1033–1044.[3]
  • Alexei Kojevnikov, Stalin's Great Science: The Times and Adventures of Soviet Physicists (Imperial College Press, 2004), ISBN 1-86094-420-5 (discusses use of Fuchs's passed on information by Soviets, based on now-declassified files)

[edit] Bibliography

  • Robert Chadwell Williams, Klaus Fuchs: Atom Spy (Harvard University Press, 1987) ISBN 0-674-50507-7

[edit] External links

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