Copenhagen: On
the verge of the nuclear age
An
introduction to the play Copenhagen (1998) by Michael
Frayn
March 20, 2018
Nicola
Cufaro Petroni USPID (Unione degli Scienziati per il
Disarmo, Bari)
CIRP-UniBa "Giuseppe Nardulli" (Centro Interdipartimentale di
Ricerche sulla Pace, Bari)
cufaro@ba.infn.it
In September 1941 a meeting occurred in the
occupied Copenhagen between Niels Bohr and Werner Heisenberg:
their exchange, however, quickly turned sour and the two
physicists abruptly parted. Nobody knows what exactly was said
that night, but everybody agrees that the talk was about the
(allied and German) nuclear weapons projects prompted by the
recent (decembre 1938) discovery of the nuclear fission. Much of
the initial controversy stemmed from a 1956 letter Heisenberg
sent to the journalist Robert Jungk where he mantains that he
had come to Copenhagen to discuss with Bohr his moral objetions
toward scientists working on nuclear weapons, but also that he
had failed to say this clearly before the conversation came to a
halt. Bohr was outraged after reading these staments feeling
that they were false and that instead the 1941 meeting had
proved to him that Heisenberg was quite happy to produce nuclear
weapons for Germany. Heisenberg historians remain divided over
their own interpretations of the event, and Michael Frayn's 1998
play Copenhagen brought more public attention to a
topic that had previously been confined just to a scholarly discussion
On March 19-20, 2018 the Teatro Pubblico Pugliese staged
in the Teatro Petruzzelli (Bari, Italy) a reprise in italian of
Frayn's play performed by the Compagnia Umberto Orsini.
The occasion was not lost to organize two public
discussions (March 14 for university students, and
March 20 for the general public in the Foyer of the Teatro
Petruzzelli) about the moral, political, historical and
technical issues popping up all along the dramatic action. One
of the two introductory talks was entrusted to this author:
following are a few documents, either assembled or surveyed to
prepare the presentation, which are listed here in cronological
order to the advantage of people interested in these topics. The
bibliography of the papers and books quoted is, however, far
from complete
Documents
Hans Bethe: Energy production in stars, Phys. Rev. 55 (1939)
p. 103, Letter
to the Editor Energy
production in stars, Phys. Rev. 55 (1939)
p. 434
The possibility of extracting energy from a fusion chain
reaction was recognized in these two papers written in the
spring of 1938, namely before the fission experiments by O. Hahn
and F. Strassman in December 1938. For this discovery of the
reactions which supply the energy in the stars Bethe was
awarded the 1967 Nobel Prize in Physics
Lise Meitner and Otto R. Frisch: Disintegration
of Uranium by Neutrons: A New Type of Nuclear Reaction,
Nature 143 (1939) p. 239
This is the celebrated Letter to the Editor of February 11, 1939
where Meitner and Frish first announced their interpretation of
the empyrical results - December 1938 - of O. Hahn and F.
Strassman as a fission (this term is here adopted for
the first time) of the Uranium nucleus
Niels Bohr and John A. Wheeler: The
Mechanism of Nuclear Fission, Phys. Rev. 56 (1939)
p. 426
On the basis of the liquid drop model of atomic nuclei, an
account is given of the mechanism of nuclear fission: it is the
first fully worked out theory of this newly discovered
phenomenon and it laid the groundwork for atomic and hydrogen
bombs. These results were still published at that time, and the
reported publication date is the fateful September 1, 1939: the
start of World War II with the german invasion of Poland Otto R. Frisch and Rudolf Peierls: Memorandum
(unpublished, March 1940)
The Frisch–Peierls Memorandum was the first technical
exposition of a practical nuclear weapon. It was written by
expatriate German physicists Otto
Frisch and Rudolf Peierls in March 1940 while
they were both working for Mark Oliphant at
the University of Birmingham in England
during World War II. The memorandum contained the first
(rather underestimated) calculations about the size of
the critical mass of fissile material needed
for an atomic bomb. It revealed for the first time that the
amount required might be small enough to incorporate into a bomb
that could be delivered by air. It also anticipated the
strategic and moral implications of nuclear weapons. It helped
send both Britain and America down a path which led to
the MAUD Committee, the Tube Alloys project,
the Manhattan Project, and ultimately the atomic
bombings of Hiroshima and Nagasaki.
Robert Serber and Edward U. Condon: The
Los Alamos Primer
(unpublished, April 1943); original
typed version
The Los Alamos Primer was a printed version of the first
five lectures on the principles of nuclear
weapons given to new arrivals at the top-secret Los
Alamos laboratory during the Manhattan Project. They
were originally given by the physicist Robert
Serber after being delivered in person on April 5–14, 1943,
based on conclusions reached at a conference held in July and
September 1942 at the University of California, Berkeley by Robert
Oppenheimer. The notes from the lecture which became
the Primer were written by Edward Condon.
The Primer contained the basic physical principles
of nuclear fission, as they were known at the time, and
their implications for nuclear weapon design. It suggested
a number of possible ways to assemble a critical
mass of uranium-235 or plutonium. Though its
information about the physics of fission and weapon design was
soon rendered obsolete, the Primer is still
considered a fundamental historical document in the history
of nuclear weapons. Its contents would be of little use today to
someone attempting to build a nuclear weapon, a fact
acknowledged by its complete declassification in 1965. In 1992,
an edited version of the Primer with many annotations
and explanations by Serber was published with an introduction
by Richard Rhodes.
The
Franck Report (unpublished, June 1945); transcribed
version
The Franck Report was a document signed by several
prominent nuclear physicists recommending that the United
States not use the atomic bomb as a weapon to prompt
the surrender of Japan in World War II. The
report was signed by James
Franck (Chairman), Donald J. Hughes, James J.
Nickson, Eugene Rabinowitch, Glenn T.
Seaborg, Joyce C. Stearns, and Leó Szilárd, it spoke
about the impossibility to keep the United
States atomic discoveries secret indefinitely, and finally
it predicted a nuclear arms race. As a consequence it
recommended that the nuclear bomb not be used, and
proposed that either a demonstration of the "new weapon" be
madeon a barren island or desert, or to try to
keep the existence of the nuclear bomb secret for as long as
possible. However the Interim Committee, appointed
by President Truman to advise him on use of the
atomic bomb, met on June 21 to reexamine its earlier conclusions
and it reaffirmed that there was no alternative to the use of
the bomb
Samuel A. Goudsmit: Alsos(1947; American Institute of Physics, 1996)
The Alsos Mission was created following the September 1943
Allied invasion of Italy with a twofold assignment: search for
personnel, records, material, and sites to evaluate the German
programs and prevent their capture by the Soviet Union. It
was established as part of the Manhattan Project's mission
to coordinate foreign intelligence related to enemy nuclear
activity. The mission, terminated on October 15 1945, was
commanded by Colonel Boris Pash, a former Manhattan
Project security officer, with Samuel Goudsmit as
chief scientific advisor. Alsos teams took most of the
senior German research personnel into custody, including the ten
leading german physicists that ended up in Farm Hall (see
later). The book is a lively account of these operations by one
of its protagonists.
David Irving: The Virus
House(W. Kimber&co, 1967;
published in the USA as The German Atomic Bomb, Simon
and Schuster, 1967) A complete history of the German atomic bomb project written
by the controversial british historian of the holocaust. It is
maybe not techically very accurate, but it presents a
comprehensive and reliable narrative of the project from the
unusual standpoint of the nazi Germany. The account of the heavy
water battle and of the Hydro factory sabotage in Norway
reads as a spy novel. The book has been written before the
publication of the Farm Hall transcripts, but the author is
aware of their existence and partially of its contents. In his
opinion the German scientists had a rather precise idea of a
reactor functioning, and even of the critical mass of a uranium
weapon: their failure is credited to the fateful error of
relying on heavy water as moderator (instead of graphite), and
primarily to the political, economical and social environment
prevalent in Germany
Otto R. Frisch and John A. Wheeler: The
discovery of fission, Physics Today 20 (1967)
p. 43
An account of this scientific breakthrough by two of its
protagonisgts: especially relevant for us are the lines where
the role of N. Bohr is elucidated in figuring out the importance
of the isotope U-235 and in discussing the possibility of
making a bomb out of it
Stanley Goldberg and Thomas Powers: Declassified
Files Reopen "Nazi Bomb" Debate, Bulletin of
the Atomic Scientists 48 (1992) p. 32
An early discussion of the newly declassified (in February 1992)
Transcripts of Farm Hall which are the starting point of a
number of subsequent studies, books and dramatizations,
including the play Copenhagen by M. Frayn (1998). In
particular the paper already points out the nowadays common
dilemma about the Heisenberg's claims of a moral explanation for
the humiliating German failure to produce the bomb.
Jeremy Bernstein: The
Farm Hall Transcripts: The German Scientists and the Bomb,
New York Review of Books, August 13, 1992
Another paper quoting and discussing notable excerpts from the
declassified transcripts. At variance with S. Goldberg and T.
Powers, J. Bernstein is a physicist and is consequently more
accurate (here and specially in his subsequent book - see later
- on the same argument) in discussing the technical points
regarding, for instance, the critical mass calculations of
Heisenberg and his possible mistakes.
Hitler's
Uranium Club, The Secret Recordings at Farm Hall
(Springer, 2001; first published by Woodbury, New York 1996)
Edited and annotated by Jeremy Bernstein, with an
Introducrtion by David Cassidy
This is a complete edition of the Farm Hall Transcripts
declassified in 1992 with an Introduction by Cassidy, and a
rather comprehensive Prologue (more than fifty pages, an essay
in its own right) about the German bomb project by Bernstein.
The other interesting feature of the book are the extensive and
careful annotations to the dialogues of the transcripts added by
Bernstein to elucidate every detail and their relevance. Being
Bernstein himself a physicist, a few of his remarks are also
rather more thechnical (albeit far from demanding) of what one
could expect in a publication for a general public. All of this
book makes a very interesting reading and looks quite sober
abouth these otherwise rather rancorous and quarrelsome topics.
Paul L. Rose: Heisenberg and
the Nazi Atomic Bomb Project, 1939-1945: A Study in German
Culture (University of California Press, 1998)
A substantial book which is rather disparaging about the role of
Heisenberg and his compromises with the nazi regime. His
positions about the moral pretensions ascribed to the German
physicist by a few analysts (and constituting the core of
Copenhagen, the Frayn play) are also well summarized in the
exchange with T. Powers on the New York Review of Books referred
later on.
Michael Frayn: Copenhagen,
a play (1998)
A fashionable dramatization of the enigmatic meeting of Bohr and
Heisenberg in the occupied Copenhagen on September 16, 1941, at
a time when the German Uranverein already existed, albeit with a
few hurdles of its own, and the Manhattan Project was just on
the verge of starting. The meeting ended abruptly in
disagreement, but the two protagonists were never subsequently
able to concur in what exactly was said that night. The play
ends with a postscript by the author himself elucidating the
historical, politcal and moral background of his work.
Thomas Powers: The
Unanswered Question, New York Review of Books,
May 25, 2000
and his subsequent exchange with Paul L. Rose: Heisenberg
in Copenhagen, New York review of Books,
October 19, 2000
The Powers paper is a review of the Frayn's play american
reprise which opened on April 11, 2000 in New York. The author
looks indeed fairly sympathetic to the Heisenberg moral
arguments that could be synthesized in a question that the
German physicist asks twice on the stage: "Does one as a
physicist have the moral right to work on the practical
exploitation of atomic energy?" This is a still embarrassing
question that could well suit several today burgeoning research
fields: cloning, artificial intelligence, genetic manipulations,
big data management ... A question, on the other hand, which is
the source of the subsequent polemical exchange with Rose (see
also his book earlier in the present list) which is instead a
representative of another group of scholars rather
un-sympathetic toward Heisenberg. Rose credits indeed the
Copenhagen meeting of more sinister intentions (intelligence on
the nazi behalf), while at the same time discrediting the German
physicists for not achieving their own aims just because of
sheer incompetence.
N.P. (Klaas) Landsman: Getting even with
Heisenberg, Studies in History and Philosophy
of Modern Physics 33 (2002) 297
This is a long and careful critical review of the previously
referred book by P.L. Rose, with many details and remarks of his
own that give to the author the opportunity of "getting even"
with Heisenberg. His opinions look consequently rather fair and
well balanced, and hence are not partisan or clearcut as that of
many other scholars discussing these topics.
Nicola Cufaro Petroni: Chronology
(March 2018; in italian)
In this file the chronologies of the main events of World
War II and both the (allied and german) nuclear programs are
placed side by side up to the end of 1941 in order to elucidate
the events predating the Bohr-Heisenberg meeting of September
16, 1941. Af few subsequent watershad dates are added to put the
events in perspective. For the time being no pretense either of
completeness or of total accuracy is made
Annex:
Fake news?
Occasionally (and especially in our age of social
news) journalists and historians bring to the fore
sensationalistic details about the German bomb project to the
effect of exposing, for instance, either that the German
physicists were indeed far more advanced of what is generally
believed, or that somehow their results were instrumental to
complete the rival Manhattan Project. In our opinion all these
new disclosures challenging the accepted narrative should be
taken with a healthy measure of cautious skepticism, as
argumented in the following few examples
1) On May 14, 1945, just after the end of the war in Europe, the
German submarine U-234 surrendered to the USA in the
Portsmouth Navy Yard. The fact that the submarine carried also
about 540 Kg of Uranium oxide remained classified until the end
of the Cold War and gave rise to speculations about the use of
this material in the framework of a supposed shortage in the
Manhattan Project. All this is said in particular in the DVD U-234
l'ultimo sommergibile produced by the Italian RAI
for the series La storia siamo noi. As a matter of fact
the precise characteristic of the said Uranium remain
unknown, it looks however unbelievable that the Germans could
possess - without using - such a huge quantity (enough for ten
Hiroshima bombs) of weapons grade Uranium: as we know,
to separate a few Kg's of U-235 factories of industrial size are
needed, and there is no known hint of that in the Nazi Germany.
If on the other hand it was just not-enriched Uranium, half a
ton is surely a valuable item, but again there was no real
shortage of (not-enriched) Uranium for the Manhattan Project. We
should remember indeed that there were four known major deposits
of uranium in 1940: in Colorado, in northern Canada,
in Joachimsthal in Czechoslovakia, and in
the Belgian Congo. All but Joachimsthal were in allied
hands. A November 1942 survey determined that sufficient
quantities of uranium were available to satisfy the project's
requirements. In particular a purchase of 1,200 tons (not just
half a ton!) of uranium ore was negotiated from the Belgian
Congo: it was being stored in a warehouse on Staten Island
while the remaining stocks of mined ore were stored
in the Congo (see Wikipedia: Manhattan project, and
references quoted therein).
2) In the same vein the Italian magazine L'Espresso
published on October 27, 2016 a reportage by R.
Brunelli: Hitler e il mistero della bomba di Hiroshima,
mantaining that at the end of the war in Europe the nazi general
Hans Kammler handed over to an American agent about 70 Kg of
Uranium (again without qualification), that are finally hinted
to be linked to the Hiroshima bomb just because of the supposed
approximate coincidence of the two weights. The same remarks of
the previous point apply even here, with the additional one that
a supposed (slightly more than) critical mass of U-235 can not
be simply tossed around in a suitcase because it would just ...
explode: even if the German physicists had their calculations
wrong!
3) A rather more reliable case is finally made in the book Hitlers
bombe (Deutsche Verlags-Anstalt, 2005) by Rainer
Karlsch: a summary can be found in Rainer Karlsch and Martin Walker: New
light on Hitler's bomb https://web.archive.org/web/20071012022154/http://physicsworld.com/cws/article/print/22270
The author mantains, on the basis of recently available russian
archives, that the German physicists (in particular the group of
Kurt Diebner) were much more advanced of what is usually
believed, and that they developed and tested some kind of
nuclear weapon: not, however, a standard nuclear weapon powered
by nuclear fission, but something closer to either a
radiological weapon (dirty bomb) or some hybrid nuclear
fusion weapon (whatever that may mean). The alleged test
was performed in Thuringia, eastern Germany, in March 1945:
according to alleged eyewitness accounts given at the end of
that month and two decades later, the test killed several
hundred prisoners of war and concentration-camp inmates. However
scrupulous in the details, even these revelations seem not
really convincing: we read for instance on the Global
Security web page https://www.globalsecurity.org/wmd/world/germany/nuke.htm
the following questioning
lines:
The historian has no real proof to back up his spectacular
theories. His witnesses either lack credibility or have no
first-hand knowledge of the events described in the book.
What Karlsch insists are key documents can, in truth, be
interpreted in various ways, some of which contradict his
theory. Finally, the soil sample readings taken thus far at
the detonation sites provide "no indication of the explosion
of an atomic bomb," says Gerald Kirchner of Germany's
Federal Office for Radiation Protection. Joachim Schulze, a
nuclear weapons expert at Germany's Fraunhofer Institute,
took a look at Karlsch's design for such a weapon and said
it would be "incapable of functioning."