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Carl Friedrich Freiherr von Weizsäcker (June
28, 1912 – 28 April 2007) was a German physicist and philosopher. He was the
longest-living member of the research team which performed nuclear
research in Germany during the Second World War,
under Werner
Heisenberg's leadership. There is ongoing debate as to whether
he, and the other members of the team, actually willingly pursued
the development of a nuclear bomb for Germany during this time.
Weizsäcker was the son of the diplomat Ernst von Weizsäcker, the elder
brother of the former German President Richard von Weizsäcker, father
of the physicist and environmental researcher Ernst Ulrich von Weizsäcker
and father-in-law of the former General Secretary of the World Council of Churches Konrad Raiser.
Born in Kiel, Schleswig-Holstein,
Weizsäcker was raised in Stuttgart, Basel, and Copenhagen. From 1929 to 1933, Weizsäcker
studied physics, mathematics and astronomy in Berlin, Göttingen and Leipzig supervised by and in
cooperation, e.g., with Heisenberg and Niels Bohr. The supervisor of his doctoral thesis was Friedrich
Hund.
His special interest as a young researcher was the binding energy of
atomic nuclei,
and the nuclear processes in stars. Together with Hans Bethe he found a
formula for the nuclear processing in stars, called the Bethe-Weizsäcker formula and the cyclic
process of fusion in stars (Bethe-Weizsäcker process, published
1937).
Background
He is the grandson of Karl Hugo von
Weizsäcker, the Prime Minister of the Kingdom of Württemberg. His
grandfather was ennobled in 1897, and raised to the hereditary
nobility with the title of Baron (Freiherr) in 1916. As such
Carl Friedrich Weizsäcker became Baron Carl Friedrich von
Weizsäcker at the age of four. After 1919, noble titles have
legally been considered parts of the family name.
Work on
atomic weapons
During the Second World War, Weizsäcker joined the German nuclear energy
project, participating in efforts to construct an atomic
bomb. As a protégé of Heisenberg, he was present at a crucial
meeting at the Army Ordnance headquarters in Berlin on 17 September
1939, at which the German atomic weapons program was launched.[1] In July
1940 he was co-author of a report to the Army on the possibility of
"energy production" from refined uranium, and which also predicted the
possibility of using plutonium for the same purpose.[2] He was
later based at Strasbourg, and it was the American capture
of his laboratory and papers there in December 1944 that revealed
to the Western Allies that the Germans had not come close to
developing a nuclear weapon.[3]
As early as August 1939, Albert Einstein had warned U.S.
President Franklin D. Roosevelt about this
research and that: "... the son of the German Under-Secretary
of State, von Weizsäcker, is attached to the
Kaiser-Wilhelm-Institut in Berlin where some of the American work
on uranium is now being repeated."[4]
Historians have been divided as to whether Heisenberg and his
team were sincerely trying to construct a nuclear weapon, or
whether their failure reflected a desire not to succeed because
they did not want the Nazi regime to have such a weapon. This
latter view, largely based on postwar interviews with Heisenberg
and Weizsäcker, was put forward by Robert Jungk in his 1957 book Brighter
Than a Thousand Suns. In a 1957 interview with the German weekly Der Spiegel,
Weizsäcker frankly admitted to the scientific ambitions of those
years "We wanted to know if chain reactions were possible. No
matter what we would end up doing with our knowledge - we wanted to
know."[5]
The truth about this question was not revealed until 1993, when
transcripts of secretly recorded conversations among ten top German
physicists, including Heisenberg and Weizsäcker, detained under Operation
Epsilon at Farm Hall, near Cambridge in late 1945, were published. The
"Farm Hall Transcripts" revealed that Weizsäcker had taken the lead
in arguing for an agreement among the scientists that they would
claim that they had never wanted to develop a German nuclear
weapon. This story, which they knew was untrue, was called among
themselves "die Lesart" (the Version). Although the
memorandum which the scientists drew up was drafted by Heisenberg,
one of those present, Max von Laue, later wrote: "The leader in
all these discussions was Weizsäcker. I did not hear any mention of
any ethical point of view."[6] It was
this version of events which was given to Jungk as the basis of his
book.
Weizsäcker stated himself that Heisenberg, Wirtz and he had a private
agreement to study nuclear fission to the fullest possible in order
to "decide" themselves how to proceed with its technical
application. "There was no conspiracy, not even in our small
three-men-circle, with certainty not to make the bomb. Just as
little, there was no passion to make the bomb...." [7]
Ivan Supek (one of
Heisenberg's students and friends) claimed[8] that
Weizsäcker was the main figure of the famous and controversial
Heisenberg - Bohr meeting in Copenhagen in September 1941. Allegedly, he
tried to persuade Bohr to mediate for peace between Germany and
Great Britain.
Postwar
career
Carl Friedrich von Weizsäcker.
Weizsäcker was allowed to return to Germany in 1946 and became
director of a department for theoretical physics in the Max Planck Institute for Physics in Göttingen (successor
of Kaiser Wilhelm
Institute). From 1957 to 1969, Weizsäcker was professor of philosophy at the University of Hamburg. In 1957 he
won the Max Planck medal. In 1970 he formulated a "Weltinnenpolitik" (world internal
policy). From 1970 to 1980, he was head of the "Max Planck Institute for the Research of
Living Conditions in the Modern World" in Starnberg. He researched and published on the
danger of nuclear war, what he saw as the
conflict between the first world and the third world, and the
consequences of environmental destruction. In the 1970s he founded,
together with the Indian philosopher Pandit Gopi Krishna, a research foundation "for
western sciences and eastern wisdom". After his retirement in 1980
he became a Christian pacifist, and intensified his work on the
conceptual definition of quantum physics, particularly on the Copenhagen Interpretation.
His experiences in the Nazi era, and with his own behavior in
this time, gave Weizsäcker an interest in questions on ethics and
responsibility. He was one of the Göttinger 18 — 18
prominent German physicists — who protested in 1957 against the
idea that the Bundeswehr should be armed with tactical
nuclear weapons. He further suggested that West Germany should declare its definitive
abdication of all kinds of nuclear weapons.
Weizsäcker died in Söcking near Starnberg. On the question on whether he
accepted his share of responsibility for the German scientific
community's efforts to build a nuclear weapon for Nazi Germany,
opinions are split.
Theory
of Ur-Alternatives
Carl Friedrich von Weizsäcker pioneered the theory of
ur-alternatives in his books "Einheit der Natur" (1971) (The Unity
of Nature, New York, 1980 (0-374-28100-9) and deeply developed it
in his book Aufbau der Physik, Munich 1985 (ISBN
3446141421, English : The Structure of Physics,
Heidelberg 2006 (ISBN 1-4020-5234-0; ISBN 978-1-4020-5234-7) and
again in his main work "Zeit und Wissen" (1992). The theory
axiomatically constructs quantum physics from distinguishing
between empirically observable, binary alternatives. Weizsäcker
uses it to derive the 3-dimensionality of space and to estimate the
entropy of a proton falling
into a black hole. The
theory represents an important contribution to digital
physics.
Awards and
honours
In 1963 Weizsäcker was awarded the Friedenspreis des Deutschen Buchhandels
(peace award of the German booksellers). In 1989, he won the Templeton Prize
for Progress in Religion. He also received the Order Pour le
Mérite.
There is a Gymnasium named after him, in the
town of Barmstedt, which
lies northwest of Hamburg,
in Schleswig-Holstein, the Carl Friedrich von Weizsäcker Gymnasium
in Barmstedt.
Notes
Regarding personal names: Freiherr is a title, translated as Baron, not a first or middle
name. The female forms are Freifrau and Freiin.
Works
- Zum Weltbild der Physik, Leipzig 1946 (ISBN
3-7776-1209-X), 2002, 14th edition, renewed and with introduction
by Holger Lyre[1]
- translation into English The World View of Physics,
London, 1952
- translation into French Le Monde vu par la Physique,
Paris 1956
- Die Geschichte der Natur, Göttingen 1948 (ISBN
3-7776-1398-3)
- Die Einheit der Natur, Munich 1971 (ISBN 342333083X)
- translation The Unity of Nature, New York, 1980 (ISBN
0-374-28100-9)
- Wege in der Gefahr, Munich 1976
- translation The Politics of Peril, New York 1978
- Der Garten des Menschlichen, Munich 1977 (ISBN
3-446-12423-3)
- translation The Ambivalence of progress, essays on
historical anthropology, New York 1988 (ISBN 0-913729-92-2)
- The Biological Basis of Religion and Genius, Gopi Krishna, New
York, intro. by Carl Friedrich von Weizsäcker, which is half the
book, 1971, 1972 (ISBN 0060647884)
- Aufbau der Physik, Munich 1985 (ISBN 3446141421
- translation The Structure of Physics, Heidelberg 2006
(ISBN 1-4020-5234-0; ISBN 978-1-4020-5234-7)
- Der Mensch in seiner Geschichte, Munich 1991 (ISBN
3-446-16361-1)
- Zeit und Wissen, Munich 1992 (ISBN 3-446-16367-0)
- Große Physiker, Munich 1999 (ISBN 3-446-18772-3)
See also
References
- ^
John Cornwell, Hitler's Scientists (Viking 2003), 232
- ^
Cornwell, Hitler's Scientists, 235
- ^
Cornwell, Hitler's Scientists, 335
- ^
Einstein's letter to
Roosevelt, 2 August 1939
- ^
DER
SPIEGEL, "...und führe uns nicht in Versuchung: Vom gespaltenen
Atom zum gespaltenen Gewissen - Die Geschichte einer
menschheitsgefährdenden Waffe", vol. 11(19) (Mai 8, 1957), p.
52
- ^
Cornwell, Hitler's Scientists, 398
- ^
CFvW August 5, 1990, Letter to Mark Walker in: CFvW, Lieber
Freund, lieber Gegner. München (Hanser) 2002, pp 277-283
- ^
Jutarnji list. "A March 2006 interview with
Ivan Supek relating to 1941 Bohr - Heisenberg meeting
(Croatian)". Jutarnji list. http://jutarnji.hr/clanak/art-2006,3,19,supek_intervju,17440.jl?artpg=1. Retrieved
2007-08-13.
External
links