Haphazard Reality: Half a Century of Science (Amsterdam Academic Archive)

375 Pages·2010·4.94 MB·English

by  H.B.G. Casimir

AUP -Casimir AAA:AUP /Crombag AAA 02-07-2010 14:06 Pagina 1
Casimir, himself a famous physicist, studied and worked with three great physi- H
cists of the twentieth century: Niels Bohr, Wolfgang Pauli and Paul Ehrenfest.In .B
.
his autobiography, the brilliant theoretician lets the reader witness the revolu- G
.

tion that led to quantum physics, whose influence on modern society turned C
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out to be many times larger than the first atomic physicists could have imag- s
i H.B.G. Casimir
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ined.
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Through his involvement in the technical-scientific and the business aspects of
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physics, through management positions at Philips Research Laboratory and as a p Haphazard Reality
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member of the Board of Directors of Philips, Professor Casimir is the ideal per- a
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son to place half a century of developments in physics within the context of a
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important events in the world.

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a Half a Century
Hendrik Brugt Gerhard Casimir (1909-2000) was a Dutch physicist who became l
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t
well-known for his important model for superconductivity (with Cor Gorter, y
of Science
1934), the Casimir effect (with Dirk Polder, 1948) and the Casimir-operator in
quantum mechanics.
The Amsterdam Academic Archive is an initiative of Amsterdam University with a new preface by
Press. The series consists of scholarly titles which were no longer available, but frans saris
which are still in demand in the Netherlands and abroad. Relevant sections of
these publications can also be found in the repository of Amsterdam University
Press: www.aup.nl/repository.
3 a
Amsterdam University Press 3 a Amsterdam Academic Archive
9 789089 642004
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haphazard reality
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The Amsterdam Academic Archive is an initiative of Amsterdam University Press.
The series consists of scholarly titles which were no longer available, but which
are still in demand in the Netherlands and abroad. Relevant sections of these
publications can also be found in the repository of Amsterdam University Press:
www.aup.nl/repository. At the back of this book there is a list
of all AAA titles published so far.
voorwerk Casimir AAA:voorwerk Crombag AAA 28-05-2010 15:06 Pagina iii
H.B.G. Casimir
Haphazard Reality
Half a Century of Science
with a new preface by frans saris
3 a
Amsterdam Academic Archive
voorwerk Casimir AAA:voorwerk Crombag AAA 28-05-2010 15:06 Pagina iv
Haphazard Reality. Half a Century of Scienceby H.B.G. Casimir
was first published [in English] in 1983 by Harper & Row Publishers, New York
(isbn0-06-015028-9).
Cover design: René Staelenberg, Amsterdam
isbn978 90 8964 200 4
nur911
© 2010 Heirs H.B.G. Casimir / Amsterdam University Press, Amsterdam
All rights reserved. Without limiting the rights under copyright reserved above,
no part of this book may be reproduced, stored in or introduced into a retrieval
system, or transmitted, in any form or by any means (electronic, mechanical,
photocopying, recording or otherwise) without the written permission
of both the copyright owner and the author of the book.
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in the science technology spiral
Hendrik Casimir was famous for his speeches; he loved to tell witty anecdotes about
the many people he knew, to make his audience laugh or at least smile. But Casimir
did not like to pose for photographers, he did not even smile. In the picture on the
back cover of his memoirs, Haphazard Reality,he looks away from the lens with a cau-
tious expression, shy perhaps, friendly yes, but not pleased.
His memoirs are worthwhile for at least three reasons: he was born into the age of
physics, and he liked to tell hilarious stories about his fellow scientists and friends;
he presents an original view of the interaction between science and technology; but
most striking is his serious somberness about our future.
He had an angel watching over him. On his first birthday in 1910, his father gave him
a philosophy book as a present with the dedication: “This book will be old by the
time you can read / but the searching of the mind is eternal indeed”. His father, a
schoolteacher and later a professor in pedagogy at Leiden University, was the founder
of the first ‘Nederlandsch Lyceum’and already a famous figure in the Netherlands.
When Hendrik started studying physics at Leiden in 1926, helped by no one less than
Ehrenfest and Lorentz, friends of his father’s, the spectacular developments in his
subject had already begun. With Ehrenfest he also met Einstein for the first time:
“Whenever I heard him speak and met him at colloquia, I was of course always duly
impressed.” Hendrik got to know more famous physicists, such as the Nobel prize
winners Paul Dirac, Max Planck and Wolfgang Pauli, who also shaped his career.
After he graduated, Ehrenfest took him along to Copenhagen, to the institute of
Niels Bohr. “In the life of a young physicist, this is the most important event ever,”
Ehrenfest said, and he introduced him to Bohr with: “Er kann schon etwas, aber er
braucht noch Prügel.” His father wondered if the man his son was going to work for
was really as famous as he had said, so he mailed him a letter addressed to: ‘Casimir,
c/o Niels Bohr, Denmark’. Only after the letter had arrived without delay he was con-
vinced.
The institute of Bohr was an important meeting place for physicists who started
their career shortly after quantum mechanics was conceived. There were frequent
conferences and other meetings, colloquia and lectures, and ultimately, the institute
produced what is now known as the ‘Copenhagen’ interpretation of quantum
mechanics. Physicists came from all over the world. Landau worked there for quite
some time, as did Dirac, Wilson, Pauli and Gamov. Some stayed only for a short while
but returned. “Those were the days,” Casimir remembers, “when every morning
brought a noble chance, and every chance brought out a noble knight.” The index of
his memoirs contains almost all Nobel prize winners in the middle of the past cen-
tury.
Casimir was22 when he was awarded his doctorate, and at 30 he was a professor at
Leiden University, but he did not think he belonged to the very top. Although the
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Casimir effect and Casimir operator are well known in theoretical physics, he used to
say: “I have sometimes found a few new things, but I am not such a great physicist
that I have added new ways of thinking nor introduced completely new physical
ideas....A man like Einstein with his relativity theory or someone like Bohr with his
quantized atoms have introduced completely new ideas to physics.” Here Casimir
was too modest, I think, for the effect that bears his name is concerned with a new
interpretation of the vacuum, which is still so productive that if he were with us
today, he would have received the Nobel prize.
After Copenhagen and Zürich, where he worked with Wolfgang Pauli, Casimir
receiveda call from Leiden. His teacher, Ehrenfest, had taken his own life. But Leiden
had become too small for Casimir, and when the Second World War broke out, he
made an exceptional move to the Philips Research Laboratories in Eindhoven. “Of
course Philips offered many advantages, certainly financially. The universities during
and after the war were very poor, whereas at Philips in principle anything was possi-
ble. You had a staff of experienced people, you could travel to university labs all over
the world almost as much as you liked, and all international journals arrived month-
ly on your desk.”
In 1943 Heisenberg visited Holland and went for a brisk walk together with
Casimir, who still remembered exactly what Heisenberg then said: “da wäre viel-
leicht doch ein Europa unter deutscher Führung das kleinere Uebel”. The similarity
with Heisenberg’s visit to Bohr in 1942 is astonishing. Casimir was also shocked, but
typical of his wisdom, he attributed the statement to his visitor being a genius
unable to imagine the effect of his words on others. A mild reaction compared to the
accusations by Bohr, or the drama by Michael Frayn in his play Copenhagen.
After the war Casimir did not return to the university; the old rooms, the old
library were still as before, without any sign of growth or renewal, no money for
equipment or travel, no possibilities to receive guest scientists from abroad. At
Philips in 1946, Casimir was promoted to Director of the Research Lab, and in 1956
he became a member of the Board. Under his guidance until his retirement in 1972,
Philips Research was one of the best research centers in the world. Casimir devoted
two chapters of his memoirs to explaining his policy of academic freedom in the
industrial research environment. He belonged to those research managers who
believed in academic freedom in industry as well, and when asked how to manage
science in industry, he categorically answered: “Don’t even try.” Of course, it helped
that in those days Philips earned its leading position with technological innovations
such as the television tube and micro-electronics.
“In my personal affairs, I was throughout my life an equally bad executive. Fortu-
nately, my wife is far more competent than I in financial and other practical matters,
so at home I left such things to her. This was well known in the laboratory....”
Casimir writes, “Once a technician had asked for a form and was waiting while I was
writing it out. ‘What is the date?’ I asked, and he said, ‘Twenty-second’ – and added,
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to tease me about not knowing the date, ‘February 1938’. By that time I had arrived
at the signature, and reacting to his teasing, I asked, ‘And what is the name, please?’
The answer came promptly, ‘Mr Jonker’ – my wife’s maiden name.”
Reflecting on industry and science after the war, Casimir takes sides in the discus-
sions on the contradictions between fundamental and applied research, and he
comes up with an original synthesis. First, he distinguishes three models: 1) science
and technology develop completely independently; 2) although scientists don’t care
about technology, they still contribute; 3) progress in technology and science is in
the hands of the military-industrial complex. Next, he dismisses all three, for it is
undeniable that technology uses scientific results, even though it may take a consid-
erable amount of time; and progress in science depends on technology, and since the
invention of the computer, this is no longer limited to experimental work. Scientists
are usually eager to use new technology; by definition, they are ‘first movers’. Thus,
Casimir introduces the ‘science and technology spiral’: technology makes use of sci-
entific results, albeit with a time lag; science makes use of technology without any
time lag. Consistent with his own management philosophy, this science and tech-
nology spiral is not managed by anybody or anything.
“I might have ended my book here,” Casimir writes in his memoirs. If he had done
so, his book would still have been worthwhile, but in that case it would have drawn
nowhere near the publicity and attention it got from the scientific community and
beyond.
“As a scientist and industrial research manager, I have good reason to be proud of the
achievements of science and technology,” Casimir writes, “but as a citizen of my
country, as a citizen of the world, as a human being, I am profoundly worried rather
than pleased.” Many colleagues were astonished by these words from such a great sci-
entist, some were upset or even hurt. How could a leading scientist, Philips director,
and also president of the Royal Netherlands Academy of Sciences and of the Euro-
pean Physical Society betray his profession so openly?
This was 1983, however, the cold war was still raging, and an enormous number of
nuclear weapons and cruise missiles hung above our heads like the sword of Damo-
cles. One mistake could set the whole world on fire and finish off all life on earth. At
the spring meeting of the Dutch Physical Society, Casimir said in connection with
the energy crisis: “Our society is not civilized enough for nuclear energy.” And in a
special issue for the 150thanniversary of the Dutch literary journal De Gids, of which
he was an editor, he wrote about a brave archeologist who would dare to start dig-
ging in the “radioactive remains of our society” in a hundred years’time. Casimir
signed petitions against the Star Wars plans of the USA, and many concerned scien-
tists followed. He opened our eyes to the uncontrolled industrial developments and
warned about the long-term effects on climate change. This was the start of the ques-
tioning of the unlimited consumption in Western society, and to his dismay Casimir
saw a new numb generation hanging in front of the Philips TV.
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Science and technology were blamed for all evil. No wonder Casimir was worried,
he was convinced that the science and technology spiral had its own dynamics and
was not managed by anybody! In his eyes, we were prisoners of the science and tech-
nology spiral. The last lines of his book read thus: “We should not let science and
technology become our masters instead of our tools.”
The cold war is over, the hydrogen bomb has not been used in contrast to all
expectations, and the first cruise missiles have already been dismantled, but for
Casimir that would not have been enough to look more pleased on the cover of the
reprint of his masterpiece.
Frans W. Saris
28 February 2010
Contents
Preface to the Series ix
Author's Preface xi
Introduction 1
1. Family Background and Schooldays 4
Family Background 4
The Origin of Our Family Name 17
Schooldays 18
Hendrik Antoon Lorentz 22
2. Development of Physics 26
Introduction 26
Nineteenth-Century Physics 27
Atomic Physics Before 1900 33
The Reality of Atoms 39
Inadequacy of Classical Theory 46
Quantum Mechanics 51
3. Early Years at Leiden 57
Ehrenfest and Pauli 82
4. Copenhagen 88
Niels Bohr 88
Bohr and Genetics 99