the
German nuclear project
The German
nuclear energy project was an endeavour by scientists during
World War II in Nazi Germany to develop nuclear energy and
an atomic bomb for practical use. Unlike the competing
Allied effort to develop a nuclear weapon the German effort
resulted in two rival teams, one working for the military,
the second, a civilian effort co-ordinated by the German
Post Office.
The nuclear
research effort most widely discussed was that of the Kaiser
Wilhelm Institute team led by the physicist Werner
Heisenberg. The second was a military team under the
scientific leadership of Prof. Kurt Diebner. This military
team was also associated with Dr. Paul Harteck who helped to
develop the gaseous uranium centrifuge invented by Dr. Erich
Bagge in 1942. Their team was part of the German Army (Heereswaffenamt
Forschungsstelle E), the Kriegsmarine (navy) had a
subsidiary team looking at nuclear propulsion for U-boats
under Dr. Otto Haxel. Konteradmiral Karl Witzell and
Konteradmiral Wilhelm Rein were military leaders of the
naval nuclear project.
The intentions of Heisenberg's team are a matter of
historical controversy, centring on whether or not the
scientists involved were genuinely attempting to build an
atomic bomb for Nazi dictator Adolf Hitler. The project was
not a military success by any measure.
effectiveness
and implications
Nuclear
Fission was discovered in 1938 when Otto Hahn and Fritz
Strassman bombarded a sample of Uranium with neutrons and
found Barium atoms as products of the reaction. This was a
surprising find at the time, and on retrospect it proved
that a few years before Enrico Fermi in Rome and the
Joliot-Curies in Paris, had produced, without knowing it,
the bursting of a uranium nucleus. In other words: nuclear
fission. Lise Meitner a refugee from Germany at the time,
was told of these results by her colleague Hahn, before
publication. She, with Otto Robert Frisch where the first to
realize the full implications of the discovery and coined
the term fission. They also gave a rough description of the
mechanisms of fission and revealed that large amounts of
binding energy were released in the process. Thus by the
beginning of World War II the scientific community was well
aware of the early German lead in this area of nuclear
physics.
The threat of a Nazi atomic bomb was one of the primary
driving forces behind the creation of the British TUBE
ALLOYS project which would eventually lead to the Allied
nuclear weapons effort: the Manhattan Project under General
Leslie Groves. Several European exiles from Germany, Italy,
Hungary etc. eventually would make significant contributions
to the Allied nuclear effort. The German government never
did finance a full crash program to develop weapons, as they
estimated it could not be completed in time for use in the
war, thus the German program was much more limited in
capacity and ability when compared to the eventual size and
priority of the Manhattan Project.
In 1945, a U.S. investigation called Project Alsos
determined that German scientists under Heisenberg were
close, but still short, of the point that Allied scientists
had reached in 1942, the creation of a sustained nuclear
chain reaction, a crucial step for creating a nuclear
reactor (which in turn could be used for either peaceful
purposes, or for creating plutonium, needed for nuclear
weapons). The U-234 submarine tried to deliver to Japan
uranium and advanced weapons technology, but after the
German capitulation, it surrendered to the US before
reaching Japan.
There has been a historical debate, however, as to whether
the German scientists purposefully sabotaged the project by
under-representing their chances at success, or whether
their estimates were based in either error or inadequacy.
Heisenberg's
1941 meeting with Bohr
In 1941,
Werner Heisenberg met with his former mentor Niels Bohr in
occupied Denmark and had a conversation outside of any other
witnesses. The exact content of their conversation has,
since the 1950s, been a matter of some controversy. The
meeting and its controversy was the subject of a Tony
Award-winning play from 1998 by Michael Frayn, Copenhagen.
There is considerable speculation on what occurred at the
real-life meeting, and the actual accounts of it from the
parties involved differ. The pro-Bohr version of the story
asserts that Heisenberg was seeking to recruit Bohr to the
Nazi nuclear effort, and offering him academic advancement
in return. The pro-Heisenberg version asserts that
Heisenberg was attempting to give Bohr information about the
state of the German atomic programme, in the hope that he
might pass it to the Allies through clandestine contacts. At
that point the German atomic programme was not progressing
well (the Nazi government had decided not to undertake the
investment required to develop a weapon during the war);
Heisenberg may have suspected that the Allies had a viable
atomic program, and hoped that by disabusing them of the
idea that the German program was also successful he could
dissuade the Allies from using an atom bomb on Germany.
Much of the initial "controversy" resulted from a 1956
letter Heisenberg sent to the journalist Robert Jungk after
reading the German edition of Jungk's book Brighter than a
Thousand Suns (1956). In the letter, Heisenberg described
his role in the German bomb project. Jungk published an
extract from the letter in the Danish edition of the book in
1956 which, out of context, made it look as if Heisenberg
was claiming to have purposely derailed the German bomb
project on moral grounds. (The letter's whole text shows
Heisenberg was careful not to claim this.) Bohr was outraged
after reading this extract in his copy of the book, feeling
that this was false and that the 1941 meeting had proven to
him that Heisenberg was quite happy with producing nuclear
weapons for Germany.
After the play inspired numerous scholarly and media debates
over the 1941 meeting, the Niels Bohr Archive in Copenhagen
released to the public all heretofore sealed documents
related to the meeting, a move intended mostly to settle
historical arguments over what they contained. Among the
documents were the original drafts of letters Bohr wrote to
Heisenberg in 1957 about Jungk's book and other topics. The
documents added little to the historical record but were
interpreted by the media as supporting the "Bohr" version of
the events. According to the archivists, the letters were
released "to avoid undue speculation about the contents of
the draft letter", which had been known about but not been
open to historians previously.
analysis and
legacy
There have
been numerous other cited factors for the failure of the
German program. One is that the repressive policies under
Hitler encouraged many top scientists to flee Europe,
including many who worked on the Allied project (Heisenberg
himself was a target of party propaganda for some time
during the Deutsche Physik movement). Another, put forth by
ALSOS scientific head Samuel Goudsmit, was that the
stifling, utilitarian political atmosphere adversely
affected the quality of the science done. Another is that
the German homeland was nowhere as secure from air attack as
was the USA. Had the many massive centralized factories and
production facilities constructed for the US bomb project
been built in Germany, they would have been prime targets
for Allied bombing raids.
In 2005, Berlin historian Rainer Karlsch published a book,
Hitlers Bombe (in German), which was reported in the press
as claiming to provide evidence that Nazi Germany had tested
crude nuclear weapons on Rügen island and near Ohrdruf,
Thuringia, killing many war prisoners under the supervision
of the SS. Some press reports, however, have reported the
book as only having claimed to provide evidence that the
Nazis have been successful with a radiological weapon (a
"dirty bomb"), not a "true" nuclear weapon powered by
nuclear fission. Karlsch's primary evidence, according to
his publisher's reports, are "vouchers" for the "tests" and
a patent for a plutonium weapon from 1941. Karlsch cites a
witness to the Ohrdruf blast and another to the scorched
bodies of victims afterwards. He also claims to have
radioactive samples of soil from the sites. At Nuremburg
trials in 1946 Nazi munitions minister Albert Speer was
questioned by prosecutors about the Ordruf blast, in an
attempt to hold Speer accountable for its victims.
Mainstream American historians have expressed scepticism
towards any claims that Nazi Germany was in any way close to
success at producing a true nuclear weapon, citing the
copious amounts of evidence which seem to indicate the
contrary. Others counter that Prof. Kurt Diebner had a
project which was far more advanced than that of Dr. Werner
Heisenberg. A recent article in Physics Today by the
respected American historian Mark Walker has presented some
of Karlsch's less controversial claims — that the Germans
had done research on fusion, that they were aware that a
bomb could potentially be made with plutonium, that they had
engaged in some sort of test of some sort of device, that a
patent on a plutonium device (of unspecified detail) had
been filed and found — as substantiated.
The Germans’ only source of heavy water, a necessary
component of some of their bomb research, was Norsk Hydros
plant in Vemork, Norway. In February 1943, a Norwegian
Commando unit sabotaged the plant. Whether this affected the
German program is not clear.
An important footnote to the German nuclear effort is that
as part of the Paris Treaties of 1955 and Adenauer's
"non-nuclear pledge", Germany has perpetually forsworn
nuclear (as well as chemical and biological) weapons. It was
this pledge that ultimately cleared the way for West
Germany's entry into NATO. |