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9 From de Broglie to Fermi

Our next five remarkable physicists were born in the ten years between 1892 and

1901. Two came from France and one from each of India, Italy and Russia.

Louis de Broglie (1892–1987)

The de Broglie family, one might almost say dynasty, is one of the most

illustrious in the history of France. Of Piedmontese origin (the name is

pronounced de Broy), they came to serve the French kings in the seventeenth

century. Some achieved military distinction; four became Marshals

of France. The first duc de Broglie was a warrior and diplomat in the first half

of the eighteenth century; his son was created a prince of the Holy Roman

Empire after leading the defeat of the Prussians in the Seven Years War.

The family remained prominent in French public life throughout the nineteenth

century, but, as well as politicians and soldiers, it ended the century

by producing two distinguished brothers, of whom the elder was a notable

experimental physicist and the younger a theoretical physicist of genius.

The family background of Louis Victor Pierre Raymond de Broglie is

an essential clue for the understanding of his long, prestigious and solitary

career. He was born in Dieppe on August 15, 1892, the youngest of a family

of five, by all accounts an adorable child, remarkably good-looking, as witnessed

by early photographs, bright, gay, overflowing with good spirits and

impish pranks. His elder sister gives the following description of him in her

memoirs:

this little brother had become a charming child, slender, svelte, with a

small laughing face, eyes full of mischief, curled like a poodle.

Admitted to the great table, he wore in the evenings a costume of blue

velvet, with breeches, black stockings and shoes with buckles, which

made him look like a little prince in a fairy tale. His gaiety filled the

house. He talked all the time even at the dinner table where the most

severe injunctions of silence could not make him hold his tongue, so

irresistible were his remarks. Raised in relative loneliness he had read

much and lived in the unreal . . . he had a prodigious memory and

308 From de Broglie to Fermi

knew by heart entire scenes from the classical theatre that he recited

with inexhaustible verve . . . he seemed to have a particular taste for

history, in particular political history . . . hearing our parents discuss

politics he improvised speeches inspired by the accounts in the

newspapers and could recite unerringly complete lists of ministers of

the Third Republic, which changed so often . . . a great future as a

statesman was predicted for Louis.

As befitted a member of the de Broglie family, the young prince was educated

at home by private tutors. In 1906, when he was aged fourteen, his father duc

Victor died. Maurice, then aged thirty-one, took a hand in the education of

his young brother.Onhis advice Louis was sent to the Lyc´ee Janson de Sailly,

where he spent three years before graduating in 1909, at the age of seventeen,

with both the baccalaur´eat of philosophy and that of mathematics.

We are fortunate in having an account of Louis’ formative years by

his brother duc Maurice: ‘Having experienced myself the inconvenience of a

pressure exercised on the studies of a young man I refrained from imparting a

rigid direction to the studies of my brother, although at times his vacillation

gave me some concern. He was good at French, history, physics, philosophy,

indifferent in mathematics, chemistry and geography, poor in drawing and

foreign languages.’ It is interesting to note that, although his sister, thanks

Louis de Broglie (1892–1987) 309

to an English nurse, was bilingual from an early age, the respectable clerics

who nurtured the young prince did not give him a taste for foreign languages.

This may help to explain his isolation from the foreign scientific

community in later years. By 1910 Louis de Broglie was a student at the

Sorbonne. He was not sure what he wanted to do; a military or diplomatic

career did not attract him. At first he read history but was repelled by the

uncritical way it was taught at that time. Next he spent a year studying law

in preparation for a career in the civil service, until he found his true vocation

through reading Poincar´ e’s epistemological masterworks, La valeur de

la science and La science et l’hypoth`ese; in the end it was physics, particularly

theoretical physics, he chose to devote his life to. However, as taught

at the Sorbonne, physics was not an intellectual adventure but a rigorous

discipline based on standard subjects such as rational mechanics and wave

optics, ignoring recent developments such as Maxwell’s electromagnetic

theory and statistical thermodynamics. Practically the only French source

for advanced theoretical physics was Poincar´ e, whose lectures on electrodynamics,

thermodynamics, celestial mechanics and other subjects Louis

de Broglie duly attended. Fortunately he could read English and German;

French translations of foreign textbooks were often of poor quality.

Louis de Broglie was deeply attached to his sister, the princess Pauline.

She was twenty years older than he was and already well known in literary

circles. Around his twentieth year she married the count Jean de Pange,

and this seems to have triggered some kind of emotional and psychological

crisis in her young brother. He experienced a change of personality, losing

the gaiety and high spirits of his youth. His self-confidence was badly shaken

when he failed an examination in general physics. He had begun to lose faith

in himself when he started reading the report of the first Solvay conference

on quantum theory. After he had studied it in depth, his confidence began

to return and he became convinced that his career would definitely be in

theoretical physics. He had now reached the age at which he needed to

discharge his obligation for military service. However, the First World War

broke out before he had been in the army for long and so he remained there

for the next six years. He began by serving as a sapper in the Corps du G´enie

and was sent to the fort at Mont Val ´ erien, where he was bored stiff. After

his elder brother Maurice had pulled strings, Prince Louis was transferred to

the radiotelegraphy section; he was based at the bottom of the Eiffel Tower,

on which a radio transmitter had been installed. Later he would say that

the practical experience he gained in this way was of value in his scientific

work.

310 From de Broglie to Fermi

As duc Maurice puts it, ‘he was able to serve his country while working

as an electrician, taking care of machines and wireless transmissions

and perfecting heterodyne amplifiers then in their infancy’. Louis did not

take lightly the waste of six of the best years of his life, but of course he was

fortunate not to have been sent to the trenches. As soon as he was demobilized

in August 1919, with the rank of ‘adjutant’ at the age of twenty-seven,

he attended a seminar given by Langevin on quantum theory and then a

course on relativity, which impressed him by its beauty. He recalled that

demobilized in 1919 I returned to the studies I had given up, while

following closely the work pursued by my brother in his private

laboratory with his young collaborators on X-ray spectra and on the

photoelectric effect. Thus I made my first steps towards research by

publishing a few results in the fields studied by my brother.

In a first series of publications I considered the absorption of

X-rays, its interpretation by the theory of Bohr, and its relation with

thermodynamic equilibrium . . . Some of the reasonings I used were

questionable but they led me to formulae which gave an acceptable

account of the facts. At the same time I had long discussions with my

brother on reinterpretation of the beautiful experiments that he

pursued on the photoelectric effect and corpuscular spectra. I

published, with him or separately, a series of notes on the quantum

theory of these phenomena which, although classical now, was not

well established then.

If Louis de Broglie had done nothing else during his long life, these notes

would be enough to immortalize his name. It is best to let him describe

the contents himself: ‘in the first, inspired by relativistic considerations,

I established the relation, well known today, between the motion of a free

particle and the propagation of the wave that I proposed to associate with it,

and showed how these new ideas gave a simple interpretation of the quantum

stability conditions for the motion of the intra-atomic electrons. In the

second I applied these ideas to photons and I sketched a theory of interference

and diffraction, compatible with the existence of photons. Finally in

the third, I showed how my conceptions led to Planck’s law for black-body

radiation and I established the now classical correspondence between the

Maupertuis principle of least action in analytical mechanics and the Fermat

principle, applied to the propagation of the associated wave . . .’

He expanded the three notes of 1923 the following year into a doctoral

thesis, and that document is the basis for what is known as wave mechanics.

Louis de Broglie (1892–1987) 311

The solitary genius whose ideas kindled those of de Broglie was undoubtedly

Einstein. It was by striving to understand, in the framework of relativity,

the dual wave–particle nature of the photon, inherent in the theory of the

photoelectric effect given by Einstein in termsof light quanta, that de Broglie

was led to the dual wave–particle nature of the electron. At the same time,

being in daily contact with the photo-electric effect, through his brother’s

laboratory, must have been a further stimulus in the search for the solution

of this riddle. The whole discovery could be summed up in the following

phrase: ‘Because the photon, which, as everyone knows, is a wave, is also

a particle, why should not the electron (or any material particle) also be

a wave?’ It is hard to overestimate the extraordinary daring and the farreaching

consequences of this simple idea, but at first it was not taken

very seriously. Ralph Fowler, the quantum expert at Cambridge, reported

on it in the British journals. Langevin gave an enthusiastic account of the

thesis to Einstein, who replied ‘Louis de Broglie’s work has greatly impressed

me. He has lifted a corner of the great veil. In my work I obtain results

which seem to confirmhis. If you see him please tell him how much esteem

and sympathy I have for him.’ Einstein reported on de Broglie’s thesis to

the Berlin Academy, thus ensuring its rapid acceptance in the scientific

world.

Heir to a rich and illustrious family Prince Louis, later duc, de Broglie’s

fame burst on him at the age of thirty-seven, with the Nobel prize for physics

rewarding one of the great discoveries of the twentieth century and bringing

fresh lustre to the de Broglie family. A new chair at the Sorbonne was

created in 1933 and occupied by him for thirty years. He was elected to the

Paris Academy in the same year, by an overwhelming majority, and became

permanent secretary at the age of fifty. He resigned at eighty-three, but continued

in an honorary capacity. He was also one of the few scientists to be

elected to the literary Acad´emie Franc¸ aise. Although he seldom left France,

he was elected a foreign associate of the National Academy of Sciences in

Washington and a foreign member of the Royal Society of London.

In 1928 his mother died without ever having realized that her son was

a genius; she took to her grave an image of him as a failure. After her death

the vast family palace in the rue de Messine was sold, with most of its contents,

and Prince Louis chose to live in a modest house in Neuilly-sur-Seine,

his home for the remaining sixty years of his life, removed from the crowds

and the noisy world. He never married but was attended by two faithful

retainers. He never owned a motor car, preferring to walk everywhere or to

take the metro. During the summers he stayed in Paris and never went on

312 From de Broglie to Fermi

holiday. When his brother Maurice died in 1960, he became duc Louis de

Broglie; before that he was known by his imperial title of Prince.

Nobody ever saw duc Louis angry or even heard him raise his voice.

Some said that he was actually a man of strong passions and dislikes but

there is no evidence for this. He was always exquisitely polite to all his visitors,

no matter who they might be. At a ceremony organized for his eightieth

birthday he said ‘I consider that the period which followed my seventieth

birthday may well have been, on the intellectual side, the most beautiful of

my life.’ He wrote copiously and well, rather like Poincar´ e, but his great

work was accomplished when he was young. He came to accept Bohr’s

notion of complementarity and Heisenberg’s indeterminancy principle.

Among the scientists of his time, Einstein was probably the only one whom

duc Louis admired unconditionally. It was Einstein’s special relativity and

his theory of light quanta that launched duc Louis on the path of his great

discovery. It was Einstein’s obstinacy in refusing the probabilistic implications

of quantum mechanics that encouraged duc Louis in his own, solitary

and in the long run fruitless, quest. If Maurice de Broglie had been for Louis

a friendly and protective elder brother, one may say that Einstein had been

his ‘spiritual elder brother’.

For thirty-three years duc Louis lectured at the Sorbonne. He took a

very exalted view of his duties as a teacher: the books that originated from

his lectures, beautifully written and carefully produced, brought instruction

and enlightenment. In his teaching he took great care when presenting his

own ideas to explain that they were not generally accepted. However, as a

lecturer in the classroom he was uninspiring. Starting scrupulously on time,

he read in his high-pitched voice and in a somewhat monotonous tone from

a sheaf of large sheets of paper written in long-hand. He always stopped

abruptly at the end of the hour and departed immediately. He also ran a

well-attended weekly seminar at which young and not-so-young theorists

could expound their ideas. A member of his seminar recalled meeting him

for the first time, when he was middle-aged:

he greeted me with great courtesy and invited me to take part in the

proceedings. I was terribly impressed. At the thought of shaking hands

with a man who was a prince of physics and a prince by birth I was

seized with an almost religious emotion. He was wearing a dark blue

suit which even then seemed slightly old-fashioned, with a wing collar

and a pearl in his neck-tie. He had a curiously high-pitched voice and

he seldom spoke. Strange as it may seem I thought this man covered

Satyendranath Bose (1894–1974) 313

with honours and glory was shy. The seminar did not start before he

had shaken hands with all the participants, numbering about twenty,

who were standing as he passed. In spite of their small number the

speaker was never interrupted, remarks and questions had to wait

until the end of the talk.

However, with a few exceptions the disciples who congregated around duc

Louis were not of the highest calibre and perhaps not always of the highest

intellectual honesty. One of the manifestations of this was the atmosphere

of admiration, not to say adulation, with which they surrounded

him. Although duc Louis never encouraged such behaviour in any way, he

never reacted against it sufficiently strongly to put it down once and for

all. Also, with advancing years, as the direction of research separated him

more and more from the mainstream, he may have felt some comfort in

being surrounded by disciples who agreed with his conceptions and devoutly

developed them in seminars and articles. Louis de Broglie died on March 19,

1987, in his ninety-fifth year.

Satyendranath Bose (1894–1974)

With the exception of Rutherford, so far all the subjects of these profiles have

been either European or American, because it seemed impossible to find

314 From de Broglie to Fermi

suitable subjects in other parts of the world. At the close of the nineteenth

century, however, the situation began to change. Outstanding individual

scientists began to emerge in other countries, and it is only to be expected

that their life-stories would be quite different from the others we have been

describing. I give one such example from India and another from Japan.

Today the contribution to science of countries such as India and Japan is

most impressive, but in many ways it is even more remarkable what was

achieved by the pioneers, who worked in such a very different milieu from

their European and American counterparts.

Satyendranath (or Satyendra Nath) Bose, generally known as S.N.

Bose in the scientific community and affectionately called Satyen Bose

in his native Bengal, was born on January 1, 1894 in Calcutta, then the

capital of British India. His father, Surendranath Bose, was an accountant

who held responsible posts in the executive engineering department of East

Indian Railways. Surendranath had an aptitude for mathematical thinking

and was interested in several branches of science; he became one of the

founders of a small chemical and pharmaceutical company. He was also

interested in philosophical studies, especially the Hindu scriptures such as

the Bhagwag-gita; at the same time he enjoyed the dialectical speculations

of Hegel and Marx. Surendranath Bose died in 1964 at the age of ninety-six,

having witnessed with pride the seventieth-birthday celebrations in honour

of his famous son the previous January. The mother Amodini Devi of

Bose, who had died twenty-five years earlier, often had to struggle against ill

health and inadequate resources to maintain a middle-class home. Although

she received no more than a nominal school education, she was a woman

of culture who showed considerable ability in managing domestic affairs.

She possessed a remarkable fortitude of will, a warm heart and a sense of

personal and family dignity.

Satyendranath was the only son and eldest child of his parents, who

also had six daughters. He inherited many good qualities and noble aspirations

from his parents and more than fulfilled their expectations of him.

Young Satyen Bose attended a neighbourhood elementary school in Calcutta

until he was thirteen years old and then went on to the excellent Hindu

school. His eyesight was very weak, but his intelligence and memory were

keen, and he had a great desire to study science. The headmaster and senior

mathematics master gave him every encouragement.

After passing out of high school in 1909, Bose entered Presidency

College, Calcutta, where he enrolled in the science courses, which were

being taught by a distinguished faculty. Among his contemporaries were

Satyendranath Bose (1894–1974) 315

several notable scholars, including Meghnad Saha, who became a close

friend. Whereas Bose came from a middle-class urban Bengali family, Saha

came from an obscure village where educational facilities were practically

non-existent. Bose came first both in the B.Sc. examination in 1913 and in

the M.Sc. two years later. He also got married during his final year in college,

to Ushabala Ghosh, the eleven-year-old daughter of a wealthy physician; as

was customary the marriage was arranged by the parents. The couple had

nine children; after two had died in infancy, two sons and five daughters

were left, all of whom received a good education.

It was a time of political unrest, and in many ways the career outlook

was not good. However, the Indianization of education was creating

opportunities for able youngsters like Bose and Saha. The University of

Calcutta, founded in 1857, was being transformed into a national institution,

free of British influence. The Vice-Chancellor and moving spirit behind

this development, Sir Asutosh Mookerji, was himself a mathematician. The

two friends decided to devote themselves to study and research in physics.

Unfortunately modern physics, such as relativity and quantum theory, was

not treated in the textbooks available to them, and they had no access to

scientific journals. Moreover, laboratories did not exist. Planck, Einstein

and Bohr were just names to them. However, Sir Asutosh was impressed by

the willingness and enthusiasm of the aspiring young scientists and agreed

to help them prepare to teach postgraduate courses in physics and mathematics.

He granted them scholarships and arranged facilities for procuring

scientific journals and working in laboratories.

Bose and Saha had already started to learn French and German in

order to be able to read the European scientific literature, but during the

First World War it was not easy for them to obtain what they needed. As

it happened, a visiting German possessed a good collection of advanced

texts and journals in German, which he lent to them. Saha chose to study

first thermodynamics, statistical mechanics and spectroscopy, while Bose

decided on electromagnetism and relativity.

In 1916 a professor of mathematics was appointed by the university,

who started postgraduate classes in applied mathematics and physics,

assisted by Bose and Saha; the following year they were both appointed

lecturers in physics. ‘We took upon ourselves the task of teaching postgraduate

students’, Bose recalled. ‘Saha taught thermodynamics and spectroscopy

in the physics department and hydrostatics and lunar theory in the

mathematics department. I was more ambitious, teaching both physics and

applied mathematics regularly. On my shoulders fell the task of teaching

316 From de Broglie to Fermi

general physics and giving all entrants a suitable introduction to mathematical

physics. I also taught elasticity and relativity.’ In 1918 a new physics

professor was also appointed, a magnetic personality who attracted many

students, most of whom worked in optics, his speciality.

Bose and Saha started to do research in statistical mechanics, publishing

their first paper in 1918. They published, in translation, an anthology

of Einstein’s papers on relativity and then went on to quantum theory.

Saha, who began to specialize in astrophysics, went to Germany on study

leave, as Bose was hoping to do one day. Some of the other younger scientists,

including Bose, decided that it was time to leave Calcutta, where the

physics department was becoming overcrowded. He secured a non-tenured

position, equivalent to assistant professor, at Dhaka, or Dacca, where there

was an enterprising Vice-Chancellor named Hartog in charge of a newly

founded university. Although it was in no sense an Islamic institution, its

students came mainly from the Muslim population, who were in the majority

in this part of Bengal. It was unusual in being residential in character,

so the students saw much more of their teachers than at other universities.

The head of department, who had been instrumental in attracting Bose to

Dhaka, was an expatriate, a Cambridge graduate who seemed to have been

appointed professor of physics mainly on the strength of his prowess on

the football field. Bose was left to lead the postgraduate work of the department;

he began by teaching thermodynamics and electromagnetism, while

increasingly becoming interested in relativity and quantum theory for his

own research.

For Bose Dhaka was an alien land, another world culturally from the

Calcutta where he grew up, but for Saha Dhaka was his homeland. Although

Dhaka is only a few hundred miles from Calcutta, the journey was an arduous

one before the days of air travel. When Saha returned from Germany

he came over to see Bose, and the discussions he had with Bose on this

visit seem to have been the catalyst for what happened next. Around 1924

Bose wrote two important papers on the statistics of radiation. The first,

called ‘Planck’s Law and the Light-quantum Hypothesis’, he submitted to

the Philosophical Magazine, which had published his earlier work. When

he heard nothing from the editor, he took the bold step of sending a copy

to Einstein. His only previous contact with Einstein had been when he

wrote for his permission to translate some of the relativity papers into

Bengali. He then wrote a sequel, ‘Thermal Equilibrium in the Radiation

Field in the Presence of Matter’, and sent a copy of that to Einstein as well,

asking whether he would recommend both papers for the Zeitschrift fu¨ r

Satyendranath Bose (1894–1974) 317

Physik, or some other German journal, and arrange for them to be translated.

Einstein replied on a postcard: ‘I have translated your work and sent it to the

Zeitschrift fu¨ r Physik for publication. It signifies an important step forward

and I like it very much. In fact I find your objections against my work not

correct . . . However, this does not matter . . . It is a beautiful step forward.’

Bose had applied to Dhaka University for two years’ leave to study

in Europe. His application was being considered when the postcard arrived.

Such words of approval from the highest authority made all the difference.

His application was promptly granted, with generous financial support, and

Bose arrived in Paris in October 1924. Just why he then remained there

instead of continuing to Berlin is something of a mystery. He contacted

Einstein, who invited Bose to come and see him, but Bose waited a whole

year before doing so. He explained afterwards: ‘I wanted to go directly to

Berlin, but I didn’t venture to go straight on because I was not sure of my

knowledge of German. I came out thinking that perhaps after a few weeks

in Paris I should be able to go to Berlin to see Einstein. However, two things

happened: (1) friends, (2) a letter of introduction to Langevin. My friends

in Paris, who received me on arrival there, took me to this boarding house

where they were staying. Then they all insisted that I should stay there.

Well, I found it convenient to be among friends.’ It appears that these friends

were Bengali nationalists, and that Bose was becoming increasingly involved

in their activities. In 1905, when Satyen was eleven years old, the autocratic

viceroy Lord Curzon had declared the partition of Bengal, an act that had

grave political consequences, arousing Bengalis to rebel against the British

political and economic domination and spurring the nationalistic Swadeshi

movement into action.

Initially Bose had planned to spend the first year of his study leave in

England and the second in Germany. Hartog had written to both Rutherford

and Bragg on his behalf; Bragg’s answer is not known, but Rutherford replied

that he could not accommodate Bose in the Cavendish. In Dhaka, it should

be recalled, Bose had to teach both theoretical and experimental physics,

and one of his main objectives was to improve his experimental skills.

He could do this in France almost as well. Langevin suggested that he

should pursue the possibility of working in Madame Curie’s laboratory,

perhaps with la patronne herself. At the interview, conducted in English, the

‘great elderly lady’ said that Bose should first improve his French, apparently

because she had had another Indian in her laboratory who, unlike

Bose, did not know much French. Later Bose spent a short while at

the Radium Institute learning about experimental work in radioactivity.

318 From de Broglie to Fermi

Meanwhile Langevin provided him with an introduction to Maurice de

Broglie, who gave him some useful experience of experimental work in X-ray

spectroscopy.

It was not until October 1925 that Bose moved to Berlin. Einstein had

written to say that the second paper, which he was not entirely happy with,

had also appeared in the Zeitschrift; Bose had replied that he had written

a third paper, which he believed met some of Einstein’s criticisms of the

second. This third paper was never published and no copies seem to have

survived. Langevin read it with approval, but apparently Bose did not ask

him to communicate it to a French journal. In the course of time it emerged

that the ideas Bose put forward in the second paper were quite valid, but by

then Bose had ceased to be active in research.

When Bose arrived in Berlin, Einstein was on his annual visit to

Leiden. As soon as he returned they met and continued to do so all the

time Bose was in Germany. Yet it should not be assumed that they talked

about physics; it might well have been politics. Bose might have asked

Einstein for his views on nationalism in India. During this period Zionism,

rather than physics, was Einstein’s preoccupation, and of course he was a

primary target of anti-Semitic propaganda. Bose also met the other leading

physicists in Berlin at that time and made a visit to Go¨ ttingen as well.

While Bose was in Europe the head of physics at Dhaka University

left and Bose was encouraged to apply for the vacant chair. Einstein gave

him a reference: ‘the recent works of Mr S.N. Bose, especially his theory

of radiative equilibrium, signify in my opinion an important and enduring

progress of the physical theory. Also in personal discussion with Mr Bose,

I have got the impression that he is a man of unusual gifts and depth, from

whom science has much to expect. He has also at his command an extensive

knowledge and certain ability in our science. As university teacher he

will certainly develop a successful and prosperous activity.’ Other referees,

including Langevin, also supported his candidature but, even so, Bose was

not offered the position until another candidate had turned it down.

So Bose became head of physics and was soon caught up in the usual

round of duties that goes with such a post. He reorganized his department,

to make it a research centre on the European model. As for his own research,

with no proper programme, his interest kept shifting from one problem to

another. He had written nothing while he was in Europe and, as he said, ‘on

my return to India I wrote some papers. I did something on statistics, and

then something on relativity theory . . . they were not important. I was not

really in science any more. I was like a comet, a comet which came once and

Satyendranath Bose (1894–1974) 319

never returned again.’ Bose also kept up an interest in experimental physics,

especially thermoluminescence and crystal structure. However, his creative

period for research was essentially over.

After the end of the Second World War, which had come close to

Dhaka, the tension between the Hindu and Muslim communities which

led to the separation of East Bengal from the rest of India was disrupting the

work of the university to such an extent that many of the faculty, including

Bose, decided that it was time to leave. In 1945 he moved back to Calcutta,

as successor to Vankata Raman as professor of physics. He wrote some

research papers on his ideas for a unified field theory and had some correspondence

with Einstein about it. In 1954 he was given a seat in the

Rajya Sabha, the upper chamber of the national parliament, but did not play

a very active role in Delhi. Two years later, after retiring from Calcutta

University, he became Vice-Chancellor of the new central university of

Visva-Bharati, which was closely associated with the ideas of the poet

Rabindranath Tagore. Earlier Tagore had invited Bose to Santiniketan and

dedicated to him his Visva-parichaya, a book giving an elementary account

of the cosmic and microcosmic world in Bengali, in recognition of Bose’s

efforts to popularize science through the mother tongue. However, Bose

gave up the Visva-Bharati post after two years, saying that he wanted to go

back to research. In 1959 he was appointed to one of the prestigious national

professorships, which left him free to work as he pleased, and he held this

for the rest of his life, dying on February 4, 1974, shortly after the celebration

of his eightieth birthday.

After he returned to India in 1926 it was twenty-five years before Bose

went abroad again, but then he travelled extensively and was often seen at

scientific conferences. A visit to Japan confirmed his belief that, even in

science, university education in India should be in the mother tongue of

the students, not in English. The great inspiration of Bose’s life was the

work and personality of Albert Einstein. To him Einstein’s personality was

‘beyond comparison’, and he was forever grateful to Einstein for the timely

encouragement he had received from him. He hoped to see Einstein again

before he died but, because of his reputation as a political radical, Bose was

refused an American visa.

It was given to Bose to make just one important discovery and to write

a four-page paper about it. The Bose–Einstein statistics continue to have farreaching

consequences in modern physics. Einstein and Bose independently

predicted that, at extremely low temperatures in a dilute, non-interacting

gas, atoms would condense to the point where they fall into the same

320 From de Broglie to Fermi

quantum state, essentially behaving like a single atom. The Bose–Einstein

condensate, predicted by theory, has recently been produced experimentally,

and its properties are being investigated. Among the elementary particles,

the boson commemorates the name of Bose, a name that has an honoured

place in the annals of physics.

Piotr Leonidovich Kapitza (1894–1984)

Piotr Leonidovich Kapitza, later known as Peter Kapitza to the world of

science, was born in Kronstadt, the island fortress on the river Neva near

St Petersburg, on July 8, 1894. His father, Colonel (later General) Leonid

Petrovich Kapitza, was a military engineer involved in modernizing its fortifications.

The Kapitzas had been landed gentry with Polish antecedents

and the family was well represented in the professions. His mother, Olga

Ieronimovna, to whom he was very close until her death in 1937, was a

specialist in children’s literature and folklore and an important figure in

the literary world of St Petersburg. Her father, General Ieronim Ivanovich

Stebnitski, was a geographer of international repute, a corresponding member

of the St Petersburg Academy and an ardent world traveller. Unusually

for his time, he arranged for his daughters to have higher education, Olga in

the humanities and Alexandra in mathematics and science.

Piotr Leonidovich Kapitza (1894–1984) 321

Aunt Alexandra played an important part in the upbringing of her

nephew Piotr Leonidovich and it was she who discovered that, although he

was somewhat backward in other respects, he had an unusually quick grasp

of arithmetic. He never overcame a certain indirectness and sloppiness of

speech and never learned to spell correctly in any language. He was admitted

to the classical gymnasium in 1905 but was transferred after a year to

the more scientifically oriented Realschule, which was much more appropriate

to his developing talents. Six years later he graduated with honours

and entered the electrochemical faculty of the St Petersburg polytechnic –

without Latin and Greek he could not enter the more prestigious university.

Kapitza’s studies were interrupted by the First World War. After serving

for two years as an ambulance driver on the Polish front, he returned

to the polytechnic and graduated in 1918. After the chaos of war and the

upheaval of the revolution, the economy of the country was in a disastrous

state. Nevertheless, a new physico-technical institute was established under

the leadership of Abraham Joff ´ e, the grand old man of Russian physics, who

recruited Kapitza to join his group of enthusiastic young scientists. There

were great shortages of food and fuel and practically no scientific equipment,

so experimental research could be carried out only on a ‘do it yourself’

basis. In spite of these difficulties, however, a surprising amount was

achieved.

Following a romantic trip to Harbin in China, soon after he had been

demobilized, Kapitza married Nadezhda Kyrillovna, daughter of General

Chernosvitov, and their son, Ieronim, was born in 1917. A second child

was expected towards the end of 1919, but disaster struck the family.

Epidemics were rife in the dreadful conditions following revolution and

civil war. Ieronim died from scarlet fever. Nadezhda was devastated by the

loss of her first child; soon afterwards she gave birth to a daughter, only

for both mother and child to succumb to the pandemic Spanish flu. Then

Kapitza’s father also died of this, and Kapitza himself caught it but survived.

Naturally he was overwhelmed by these tragic events and unable to

continue working.

Then something happened that not only distracted him from his grief

but changed the course of his life. This was the setting up, on Joff ´ e’s initiative,

of a commission of the Soviet Academy of Sciences for renewing

scientific relations with other countries. Besides Joff ´e himself, an important

member of the commission was the naval engineer and applied mathematician

Admiral A.N. Krylov, later to become Kapitza’s second father-in-law.

Both Joff ´e and Krylov formed a high opinion of Kapitza’s scientific gifts and

322 From de Broglie to Fermi

wanted to help in his difficult personal situation; appointing him to join the

commission seemed a good way to do this.

Travel abroad at that time was not easy for Soviet citizens because

few other countries maintained diplomatic relations with theirs. The commission

set out early in 1921 and, as soon as they had travelled as far as

Berlin, began procuring scientific equipment. Kapitza wanted to go further

west, but neither France nor the Netherlands was prepared to risk admitting

someone who might prove to be a Communist agitator. However, Britain

was more accommodating and Joff ´e succeeded in obtaining the necessary

visas.

So Kapitza and Joff ´e arrived in England and early in June started a

round of scientific visits, which culminated in a most significant visit to

Cambridge in July. They were received very cordially by Rutherford but,

when Kapitza asked whether he might work in the Cavendish for a few

months, Rutherford was rather discouraging, saying that the laboratory was

already very crowded and it would be difficult to find room for another

person. Rutherford was rather taken aback when Kapitza replied by asking

what accuracy he aimed at in his experiments. The answer to this seemingly

irrelevant question was two or three per cent and Kapitza then pointed out

that, since there were about thirty researchers in the Cavendish already, one

more would hardly be noticed since it came within the experimental error.

This ingenious approach persuaded Rutherford to admit Kapitza after all. As

a postscript, it may be mentioned that a year later Kapitza asked Rutherford

why he had agreed to take him on and Rutherford laughed and said

‘I can’t think why but I’m very glad that I did.’ Later he came to regard

Kapitza almost as a surrogate son.

Kapitza joined the Cavendish in July 1921 and, although the original

plan was for him to stay only over the winter, he remained for thirteen years.

His introduction to Cambridge life and his impressions of Rutherford and

the Cavendish are vividly described in the letters he wrote at frequent intervals

to his mother Olga. The usual initiation of new research students was

a month or two of practical work in the Cavendish attic under Chadwick’s

supervision; in fact, Kapitza’s skill and assiduity were such that Chadwick

was satisfied after only two weeks. By early August Kapitza, at Rutherford’s

suggestion, was studying how the energy of the alpha particle falls off at the

end of its range. This project was brought to a successful conclusion with

amazing rapidity.Within nine months of the conception of the idea, he was

already drafting a paper for publication and by June it was sent off. He wrote

to his mother that ‘Today the Crocodile summoned me twice about my

Piotr Leonidovich Kapitza (1894–1984) 323

manuscript . . . it will be published in the Proceedings of the Royal Society

which is the greatest honour a piece of research can achieve here. Only now

have I really entered the Crocodile’s school, which is certainly the most

advanced school in the world and Rutherford is the greatest physicist and

organizer. It is only now that I have felt my strength. Success gives me wings

and I am carried away by my work.’

Crocodile was a nickname Kapitza invented for Rutherford. As he

explained: ‘in Russia the crocodile is a symbol for the father of the family

and is also regarded with awe and admiration because it has a stiff neck

and cannot turn. It just goes forward with gaping jaws – like science, like

Rutherford.’ He wrote again to his mother: ‘the Crocodile is taken with

my idea and thinks it will succeed. He has a devilish feeling for experiment

and if he thinks something will come out of it that is a very good

omen. His attitude towards me gets better and better’ and then, ‘the preliminary

experiments were completely successful. I am told that the Crocodile

speaks of nothing else now and I shall remember my last conversation with

Rutherford as long as I live. After a whole lot of compliments he said:

“I should be very happy if I could have the possibility of creating a special

laboratory for you in which you could work with your own students.”’

Meanwhile Kapitza’s official position in Cambridge was rapidly being

consolidated. In June 1923 he received the degree of doctor of philosophy

and soon afterwards he was awarded a Clerk Maxwell scholarship. Eighteen

months later he was appointed assistant director of magnetic research, a

university post. He was elected a research fellow of Trinity College, which

enabled him to live in college up to the time of his second marriage. In the

spring of 1927 Kapitza went to Paris and wrote to Rutherford: ‘I am going

to be married. What do you think about it? I feel you are rather angry. This

is why I propose to have no honeymoon and bring my wife in a few days

time after my wedding to Cambridge.’ His bride was Anna Alekseyevna

Krylova, daughter of the Admiral Krylov mentioned earlier. Although her

father stayed in Russia after the revolution, her mother emigrated to Paris

and it was there that Anna completed her training as an archaeologist. The

marriage was a very happy one. Anna was not only a charming hostess

to their many friends and an accomplished artist, but also a great support

to her husband in the difficult times which lay ahead. Two children were

born in their Cambridge period: in 1928 Sergei, who became a distinguished

physicist and successful popularizer of science for Soviet television, and

three years later Andrei, who became a well-known Antarctic explorer and

geographer.

324 From de Broglie to Fermi

In 1929 Kapitza was elected to the Royal Society, at a time when

it was relatively closed to foreigners, and almost simultaneously to corresponding

membership of the Soviet Academy. The following year he was

appointed to a Royal Society Messel professorship, and the special laboratory

Rutherford had said he would like to create for him took shape as

the Royal Society’s Mond laboratory. At the opening of the building by

Stanley Baldwin, as Chancellor of the University, a bas relief of Rutherford

just inside the main entrance and another of a crocodile just outside, both

sculpted by Eric Gill, were revealed. Speeches were made by Baldwin,

Rutherford, Kapitza and Lord Balfour, the former prime minister. Baldwin’s

speech duplicated Rutherford’s almost word for word, owing to his having

picked up an advance copy of Rutherford’s under the impression that it was

his own.

Kapitza had many interests and skills outside his scientific work. One

of his early enthusiasms was the internal combustion engine. Soon after his

arrival he bought a motor cycle and managed to crash it, without serious

injury. Before long he moved up to a car and acquired a reputation for reckless

driving. One of his hobbies was repairing watches and clocks, another

was conjuring. He was fond of boasting and exaggeration and had boundless

self-confidence, which was usually justified. Cheerful and outgoing, a great

charmer and excellent company, he loved an argument, found something

interesting or amusing to say on almost any subject. He frequently dined in

the college hall during his time as a fellow, but at Cambridge he missed the

lively discussions of the Joff ´e seminars and started something similar of his

own, a scientific circle that soon became known as the Kapitza Club. This

continued for twelve years after he had left Cambridge, but he organized a

similar one in Moscow. It is time to explain how he came to be back there.

Kapitza was rather proud of his unusual situation of directing a prestigious

laboratory in Cambridge while remaining a Soviet citizen and being

able to go in and out of the Soviet Union at will. From 1926 on he visited

Moscow nearly every summer, taking care that his permission to return to

Cambridge was underwritten by people high up in the Soviet political and

scientific establishment. During these visits he gave lectures, spent time

with his mother and usually managed to have a good holiday in the Caucasus

or Crimea as well. Although his friends wondered whether his exclusive

status could continue indefinitely, Kapitza laughed off any warnings and in

1934 made his usual summer visit, accompanied by his wife Anna. When

they were preparing to return to England Kapitza was informed that his permission

to leave the Soviet Union had been revoked. He thought that the

Piotr Leonidovich Kapitza (1894–1984) 325

problem might have arisen because the authorities had developed exaggerated

ideas of the technological relevance of his work, a situation for which

he was partly to blame.

However, another explanation seems more likely. The distinguished

physicist George Gamov decided not to return to the Soviet Union after the

Solvay conference of 1933 and when he settled in the USA he was stripped of

his Soviet citizenship. His case may well have influenced the treatment of

Kapitza, who was utterly devastated by his inability to return to Cambridge.

At first the problem was kept secret, so that the Soviet authorities could

retreat without loss of face, while all kinds of efforts were made behind

the scenes. Although Kapitza had contacts at high level, these efforts led

nowhere because, he suspected, it was Stalin himself who had decided that

he must remain in the Soviet Union. Anna was allowed to return to the

children in Cambridge and begin the difficult task of winding up their affairs

there, but it was not until the end of 1935 that the family could be reunited

in Moscow.

Meanwhile Kapitza, after a period of feeling very frustrated and miserable,

began to cooperate in the planning of a new institute, like the Mond,

of which he would be director. Life for the family became easier; they were

assigned a comfortable and central flat, a good car and other privileges. The

Institute for Physical Problems was in part modelled on the Mond laboratory,

but it was on a larger scale; the director’s office was immense, there

was a spacious lecture theatre and there was ample office accommodation,

essential for the paperwork generated by the formidable Soviet bureaucracy.

The building was attractively situated on the Lenin hills, with gardens and

parks around it. There was a magnificent house nearby for the Kapitzas

to live in. The institute was provided with staff of high quality. He had

to convince the authorities that his work lay primarily in pure rather than

applied physics and that he could do nothing useful unless he had equipment

and other facilities comparable with those he had enjoyed in Cambridge.

Negotiations were begun to bring him what he required.

So Kapitza settled down to research again and within a year made his

greatest discovery, the superfluidity of liquid helium. However, he lacked

the freedom he had enjoyed in Cambridge. From the mid 1930s Soviet scientists

found themselves increasingly cut off from their colleagues in other

countries. They were barred from going abroad for any length of time and

forbidden to publish outside the Soviet Union, even private correspondence

was not free of risk. However, Kapitza was able to take liberties that other

Soviet scientists were not. Notably, he was able to use his influence to

326 From de Broglie to Fermi

protect at least a few of his colleagues during the purge of the late thirties,

as in the case of Lev Davidovitch Landau, the head of the department of theoretical

physics at his institute. Landau was arrested in 1938, like so many

others during the Great Terror. He was held in the Lubyanka prison for a

year, after being accused of being a German spy, and would not have survived

much longer. Kapitza bravely went to the Kremlin and announced that he

would resign unless Landau was released, and eventually his intervention

was successful.

In 1939 Kapitza was elected a full academician, but there were signs

of trouble in store. Officials kept arriving to inspect the activities of the

institute, and eventually he was informed that ‘P.L. Kapitza, having shown

a cavalier attitude to both Soviet and foreign achievement in the technology

of oxygen production, and having failed to meet the scheduled dates for

introducing new installations into the metallurgical industry . . . is relieved

of his duties as Director of the Institute of Physical Problems.’ The underlying

reason for this action was probably Kapitza’s refusal to work in the organization

set up under Beria, the head of the NKVD, to develop the Soviet

atom bomb. Kapitza is said to have written to Stalin that Beria was ‘like the

conductor of an orchestra with the baton in his hand but without a score’.

Beria wanted to arrest Kapitza for such insubordination, but Stalin, in his

unpredictable way, perhaps because he admired Kapitza’s courage, vetoed

this proposal and said that dismissal would be sufficient.

Although he was no longer head of the Institute of Physical Problems,

Kapitza retained his position and salary as a full academician and went to

live at his country house at Nikolina Gora, where he managed to carry on

scientific work while virtually under house arrest. Most of his effort went

into building up a laboratory in various outhouses where, aided by his sons,

particularly Sergei, he could continue experimental work, albeit only on

relatively unexciting projects. While atomic physics elsewhere was moving

rapidly ahead using particle accelerators and other new equipment, he was

unable to contribute to this. Even after he had been reinstated in 1954 and

could return to Moscow, he was still without the facilities he needed for the

kind of experimental work at which he excelled. Nevertheless, he began to

think about the possibility of developing a defence against atomic bombs

using extremely powerful microwave emissions. Later he transferred his

attention to the problem of generating energy through nuclear fusion.

For thirty years Kapitza was denied the opportunity to accept invitations

to travel beyond the countries of the eastern bloc, until in 1965

he was allowed to travel to Copenhagen to receive the Niels Bohr gold

Jean-Fr´ed´ eric Joliot (1900–1958) 327

medal of the Danish Engineering Society. The next year he was awarded

the Rutherford medal of the Institute of Physics and returned to England

after a lapse of thirty-two years. He received a particularly warm welcome

in Cambridge; many friends of his youth were still there. He returned to

England twice more, in 1973 to receive the Simon Memorial prize of the

Institute of Physics and three years later to give the Bernal Lecture at the

Royal Society. He was also able to visit other countries to receive honorary

degrees and other distinctions. The culminating event was the Nobel prize

in 1978 for his work in low-temperature physics, especially the discovery

of superfluidity.

The Kapitzas continued to lead an active social life, enjoying the company

not only of their extended family but also of a wide circle of friends.

On his eightieth birthday the Soviet intelligentsia flocked to Nikolina Gora

for a huge celebration. Five years afterwards he suffered a severe stroke and

died on April 8, 1984 after a few days in hospital. The announcement of

his death in Pravda was signed by all the members of the politbureau as

well as all the leading Soviet scientists. A memorial meeting took place at

the institute, a moving occasion with many personal recollections by close

colleagues and friends.

As the years passed, Kapitza had become more and more accustomed,

or at least reconciled, to life in his homeland. No matter how muted his

criticism, however, he insisted on freedom to criticize. Being neither an

oppositionist nor a political opportunist, he based his collaboration with

the most unsavoury political authorities on the principle of compromise.

He did not find it easy to establish and maintain this kind of compromise.

By withholding fervour from his arguments, Kapitza would have acted

against his conscience and dignity. By saying too much, he would have

had to confront the powers he was trying to placate. He did not enjoy the

game, but, with only a few exceptions, he succeeded in avoiding its dangers.

He knew enough to restrict his comments to very specific topics of science

and science policy. The authorities awarded him Stalin prizes in 1941

and 1943, the Order of Lenin in 1943, 1944 and 1945, and, amongst other

marks of distinction, the Soviet Union’s highest civil title: Hero of Socialist

Labour.

Jean-Fr´ed´eric Joliot (1900–1958)

In dealing with husband-and-wife partnerships it seems necessary, for a satisfactory

profile, to choose one or other as the principal subject. In the case

of the Curies, Marie rather than Pierre was chosen; in the next generation

328 From de Broglie to Fermi

this is balanced by choosing Fr´ed´ eric rather than Ir `ene Joliot-Curie. Jean-

Fr´ed´ eric Joliot was born on March 19, 1900, in a small house in the smart

sixteenth arrondissement of Paris. Earlier in his life his father Henri, the son

of a steelworker from Lorraine, had been a soldier. He was called up during

the war of 1870, at the age of twenty-seven, and took an active part in the

Paris Commune, after which he was forced to leave France until an amnesty

was declared. Fr´ed´ eric’s mother Emilie, whose maiden name was Roederer,

came of an Alsatian family. Her father had been sauce-cook to Napoleon III

and as such the only servant permitted to be present at the Emperor’s meals

and, quite frequently, converse with him. She retained the austere manner

of her Protestant background but was fundamentally liberal. Her great good

nature and deep sense of justice had a profound influence on her son.

Fr´ed´ eric, the youngest of six children, was born when his mother

was already forty-nine. Two of his brothers died young and a third was to

be killed in the course of one of the first engagements of the First World

War. At the age of ten Fr´ed´ eric was sent to boarding school at the Lyc´ee

Lakanal in Sceaux. He was more interested in sport, particularly football,

than in academic school-work. He was not a well-behaved child: ‘I caused

my poor mother a great deal of worry, particularly when I went shopping

Jean-Fr´ed´ eric Joliot (1900–1958) 329

with her and stole the sweets and fruit which were on display.’ His father

owned a successful wholesale business in dry goods, which was entrusted

to a manager. Fr´ed´ eric often accompanied his father in shooting, fishing

and other such pursuits, becoming an excellent shot and fisherman in the

process. There was also music at home; his father performed on the French

hunting horn.

The death of Henri Joliot and changes in the family fortunes caused

the Joliot family to leave the affluent sixteenth arrondissement and set up

house in the fourteenth, the Montparnasse quarter near the ‘Lion of Belfort’,

that symbol of the Paris Commune. The Lyc´ee Lakanal was replaced by a

municipal school at which Fr´ed´ eric prepared himself for the higher-level

Ecole de Physique et de Chimie. He failed the entrance examination in

1918, at the end of the First World War; when he tried again the next year

he was successful, but a major illness delayed his admission until October

1920. At the end of the first year students had to choose between physics and

chemistry. The director of studies, as we know, was the charismatic physicist

Langevin, whose lectures on electricity were a revelation to his pupils.

Fr´ed´ eric chose physics and became a life-long disciple of Paul Langevin.

All those who were taught by Langevin were in some degree affected

by the experience, since he was no ordinary teacher. They tended to copy his

characteristic tricks and attitudes, such as moving the hand slowly backwards

and forwards over the chair, or leaving the blackboard and insistently

going to make a white mark with the chalk on the radiator. He taught them

that science was something living, that a teacher must convey the value and

importance of what has already been achieved, while making the audience

realize that everyone can make an original contribution to the edifice that

is being constructed. ‘When he talks about science’, said Marguerite Borel,

‘about literature, about philosophical theories – he understands everything

and is interested in everything – his very beautiful chestnut eyes and his

whole face light up.’

After graduating in 1924, Fr´ed´ eric underwent six months of full-time

training as an officer cadet in the artillery reserve, at the end of which

he became an assistant in Marie Curie’s laboratory. It was there that he

began his professional career in physics and met Marie’s daughter Ir `ene.

Ir `ene was green-eyed with short cropped hair and rather awkward in her

movements. She had inherited her father’s noble brow and her mother’s

bright and limpid eyes. She also inherited the shyness of both parents as

well as their abilities, and had great difficulties in greeting and dealing with

strangers. Even more than her mother, remarked Einstein, the main way

330 From de Broglie to Fermi

she expressed her feelings was by grumbling, just like a grenadier. Ir `ene

became more sure of herself as she grew up, but people found her excessively

self-centred. Her imperturbable calm and her direct manner in replying to

questions made her seem cold and somewhat haughty.

Marie Curie was a firm believer in the prime importance of education.

In France, at that time, the quality of school education was not outstanding.

It was mainly for Ir `ene’s sake that Marie organized a co-operative

with a group of like-minded academics from the Sorbonne, where each gave

some time teaching the ten boys and girls who belonged to it. This lasted

only two years, partly because the teachers were too overworked to give it

the necessary share of their attention and partly because too much of the

children’s time was spent travelling from place to place. Ir `ene obtained her

basic scientific education from the cooperative. After it closed she was sent

to the Coll`ege S´evign´ e, a private school, for two years’ study towards the

baccalaur´eat. When the war broke out, she was ready to enter the Sorbonne.

The girls were at l’Arcouest, where they were joined by their mother. ‘You

and I’, she told Ir `ene, ‘will try to make ourselves useful.’ To start with, both

girls helped to gather in the harvest. Later Ir `ene supported her mother’s

radiological work and, once the war was over, she became her laboratory

assistant. Eve, still just a teenager, was able to gain more of her mother’s

personal attention. She was more approachable than her sister, but she wrote

that ‘in spite of the help my mother tried to give me, my young years were

not happy ones’. Both their mother and grandfather Curie were closer to

Ir `ene than to Eve. In 1921 the daughters accompanied their mother on a

strenuous visit to the USA. In 1925 Ir `ene took her doctorate with a thesis

on the alpha rays of polonium, and that was the year in which she met

Fr´ed´ eric Joliot.

Ir `ene’s position in the laboratory was a special one, as daughter of

la patronne; moreover, she had great knowledge of radioactivity. She was

three years older than Fr´ed´ eric and seemed at first to be his opposite in

everything. She was as calm and serene as he was impulsive. Being by nature

very reserved, she found it difficult to make friends, while he was able to

make social contact with everyone. She took little interest in her appearance

and dress, while he was good-looking, elegant and always a great success

with the opposite sex. In argument Ir `ene was incapable of the least deceit or

artifice or of making the smallest concession.With an implacable obstinacy

she would present her thesis, confronting any opposition head on. Fr´ed´ eric,

on the other hand, without conceding a point, had a wonderful ability to put

his opponents in a frame of mind where they could accept his arguments.

Jean-Fr´ed´ eric Joliot (1900–1958) 331

As well as science, Ir `ene enjoyed French, English and German poetry.

From childhood she had also been keen on sport; she excelled chiefly at

swimming and skiing. She had a love of the natural world, especially the

mountains, where she several times had to stay because of pulmonary infections.

Her exterior, which tended to be cold, concealed a passionate nature. It

was in the course of long walks through the forest of Fontainebleau, talking

of physics, art and religion, that she and Fr´ed´ eric realized that they were

meant for each other.

They were married on October 9, 1926. Out of respect for Ir `ene’s

famous parents, they adopted the name Joliot-Curie. Although there was

nothing unusual in doing this, Marie was not pleased, and both professionally

and academically the young couple called themselves the Joliots

most of the time. Like her mother, Ir `ene never learned to cook, but Fr´ed´ eric

could be quite a competent chef on occasion. Their daughter H´ el `ene, born

in 1926, and son Pierre, born in 1932, also became physicists of distinction.

Owing to pleurisy, Ir `ene was slow to recover her strength after the birth of

H´ el `ene. Except for taking vacations in the mountains, she tried not to let

poor health affect her life. She carried on with her scientific work as before,

working straight through her second pregnancy, but after the birth of Pierre

she always felt tired and was never able to regain her previous weight. It

is generally believed that at this stage she was solely suffering from the

tuberculosis which was latent in her mother.

Just like Marie and Pierre, Ir `ene and Fr´ed´ eric worked together on

research. Quite soon they obtained some exciting experimental results but,

because they were not so interested in the theoretical side of physics, they

failed to interpret them correctly. As early as 1920 Rutherford had speculated

on the existence of the neutron. What the Joliots had found essentially

verified his conjecture, but they did not realize this and it was left to Rutherford’s

colleague Chadwick to establish the connection. This was not to be

the only time when the Joliot-Curies just missed making a fundamental discovery.

In 1932, they went off for a fortnight to the scientific station at the

Jungfraujoch, high in the Bernese alps. Here they combined research into

cosmic rays with a certain amount of skiing. Shortly afterwards American

researchers announced the discovery of the positron, and, when the Joliots

came to analyse more closely the results they had just obtained, they saw

that they too had found evidence of its existence without realizing it.

They had been invited to give a report on their latest experimental

work at the forthcoming Solvay conference in Brussels, where Langevin

was to be chairman. Fr´ed´ eric made the report, but in the subsequent

332 From de Broglie to Fermi

discussion the interpretation he gave of their results was strongly attacked,

particularly by Lise Meitner. It was generally believed that they must be

mistaken. After returning to Paris the Joliots set about vindicating themselves.

On a historic January day in 1934 they found conclusive evidence.

Artificial radioactivity had been created, and a new era had begun. Almost

at once the news spread around the world. For the Joliots the immediate

consequence was the award of the Nobel prize in chemistry for their synthesis

of new radioactive elements (the physics prize went to Chadwick).

They used some of the prize money to move out of central Paris to Sceaux;

and they also acquired a chalet in the Alps, where they used to go skiing.

Sadly, Marie Curie was no longer alive to hear of their success.

Both the Joliots were active in left-wing politics. Ir `ene had been influenced

by the radical politics and anticlericalism of her grandfather Curie

and, like her mother, she took a keen interest in the social and intellectual

advancement of women. In Fr´ed´ eric’s case it was his liberal-minded

mother who was more influential, while as a student he had been strongly

influenced by the left-wing views of Langevin. The Joliots firmly supported

the republican cause in the Spanish Civil War. While strongly disagreeing

with its policy of non-intervention, they joined the French Socialist Party.

In 1936 Ir `ene served briefly as Under-Secretary of State for national education

in L´eon Blum’s Popular Front government. Friends were surprised that

she was prepared to do so, but the fact that this was the first time women

had ever been included in a French government gave it a special significance.

In France, women still did not have the right to vote in elections.

She explained: ‘Fred and I thought I must accept it as a sacrifice for the

feminist cause in France, although it annoyed us very much.’ Attendance at

any sort of committee meeting was anathema to her, but the position gave

her the opportunity to link science and national development. It was agreed

that she would hold the office only for a short while, after which her friend

Jean Perrin would take over and she could return to her scientific work, but

before this could happen L´eon Blum’s government was forced out of office

in the aftermath of severe economic distress and social unrest.

In 1935 Fr´ed´ eric was made professor of nuclear chemistry at the

Coll`ege de France; two years later Ir `ene was appointed professor at the

Sorbonne. Fr´ed´ eric designed the first cyclotron built in western Europe and,

by the start of 1939, was using it to demonstrate fission by physical means,

proving that many neutrons are produced by fission, that such reactions

can be developed in explosive chains and that nuclear reactions can be controlled

to release great quantities of energy. However, during the same year,

Jean-Fr´ed´ eric Joliot (1900–1958) 333

fearful of Hitler’s power and the misuse of the chain reaction, the Joliots

suddenly ceased publishing their research.

After the Second World War had broken out, Fr´ed´ eric placed the principle

of the nuclear reactor on record and deposited it in a sealed envelope at

the Paris Academy, where it remained until it was opened in 1949. During

the war he, as a captain in the artillery, was responsible for coordinating the

war-effort of various French scientific laboratories. When he heard that

the Germans were trying to acquire the Norwegian stock of heavy water,

the world’s largest, he realized that it must be for use in atomic research. In

a remarkable coup he negotiated the loan of the heavy water for the duration

of the war and organized its transport to France, under the eyes of the

Germans. The consignment arrived at the Coll`ege de France, but events

were moving rapidly. The German army had broken through and was about

to enter Paris. The material was promptly sent on to England for safety, thus

seriously impeding the German project to build a nuclear reactor. He also

thwarted German efforts to seize the cyclotron and the stock of radium.

In June 1940, certain French scientists were told to hurry to Bordeaux and

await further orders. When they had arrived in Bordeaux they were taken

to a British ship, which was ready to evacuate 150 scientists and engineers.

However, some of them did not get the message in time; others came without

their families and, realizing only on arrival that the order meant evacuation,

did not wish to leave alone, so that only fifty sailed in the end; most

of those who remained were in non-occupied France. All efforts to convince

Joliot that he had better take the opportunity to leave for England were in

vain, but two leading members of his research group did so and resumed

their work in the Cavendish, where they played a vital role.

Unlike Ir `ene, Fr´ed´ eric joined the French Communist party, to which

many of the scientific left belonged. ‘I was impressed’, he said, ‘by the generosity,

courage and hope for the future that these people in my country

had. They seemed willing to do the most to give France social reform.’

Until then it had been difficult to be a Communist in France because of the

pact between Hitler and Stalin, but now the Germans repudiated this and

invaded Russia. As a leader of the National Front, centred at the university,

Fr´ed´ eric stood in the forefront of the Resistance movement. Pretending to

be still busy with theoretical investigations of the atom, he was actually

directing the manufacture of explosives and radio equipment for the Resistance,

and he also hid the staff of a clandestine newspaper in the laboratory.

When the Germans became suspicious, he sent Ir `ene and the two children

to Switzerland, while he remained in Paris under an assumed name.

334 From de Broglie to Fermi

As we shall see, scientists in other countries had by then taken the lead

in nuclear research. Ten years previously, however, it was France that led the

world in research on the possible liberation and utilization of atomic energy.

Only two days after the liberation of Paris Fr´ed´ eric was appointed director of

the National Centre for Scientific Research. He was promoted to the rank of

Commander of the Legion of Honour, decorated with the Croix de Guerre

and elected to the Paris Academy. Then President de Gaulle named the

Joliots as members of the French Atomic Energy Commission. Fr´ed´ eric, the

High Commissioner, stated that ‘French science does not want to have anything

to do with atomic research except for peace. All our efforts are being

utilized in the development of this tremendous energy for the advancement

of humanity.’ Ir `ene, speaking of her mother, said that, like Pierre Curie, she

had strongly believed that science should resolve human problems in the

sense of making happier lives possible. ‘Its use for destruction seemed to her

a desecration’, she continued, ‘In her eyes no political consideration would

have justified the use of the atomic bomb.’

In the same year of 1946 Ir `ene was appointed director of the Radium

Institute, founded by her mother and endowed by Carnegie. She was now

forty-nine years old and failing in health, but nothing could keep her away

from her work. Chadwick has given a picture of her at this time:

her parents were both persons of strong and independent mind, and

Mme. Joliot-Curie inherited much of her character as well as her

scientific genius. She knew her mind and spoke it, sometimes perhaps

with devastating frankness, but her remarks were informed with such

regard for scientific truth and with such conspicuous sincerity that

they commanded the greatest respect in all circumstances. In all her

work, whether in the laboratory, in discussion or in committee, she

set herself the highest standard and she was most conscientious in the

fulfilment of any duties she undertook.

In 1949 Ir `ene proudly watched Fr´ed´ eric direct the construction and

successful demonstration of France’s first atomic pile. By now, however,

the war-time alliance with the Soviet Union was over, and their outspoken

left-wing views were creating problems. The Joliots supported uncritically

the policies of Stalin, while being highly critical of the USA. On a visit to

America during the Cold War, Ir `ene was briefly detained on Ellis Island;

when she applied for membership of the American Chemical Society, her

application was rejected. In 1950, French science was shocked when Fr´ed´ eric

was removed from his post on the Atomic Energy Commission. Ir `ene served

Enrico Fermi (1901–1954) 335

her full term of five years but was not included in the reorganization in

1951. Time and again she denounced scientific secrecy and appealed for

the free circulation of scientific ideas and discoveries. In the 1950s she had

to undergo surgery repeatedly; her health was deteriorating rapidly. ‘I’m

getting lazy’, she told her friends, but she was wasting away from too much

radiation, contracted during her war work. On March 17, 1956 she died of

leukaemia in the hospital named after her parents. So controversial were

the Joliots that Ir `ene, the second most famous French woman scientist, was

given a state funeral only after heated debate.

Fr´ed´ eric’s devotion to science was accompanied by an outspoken dislike

of many traditional institutions (clerical and political) and a deep concern

for world peace. He was first president of the World Federation of

Scientific Workers and of the World Council for Peace. He also played

an active part in the formation of the Educational, Scientific and Cultural

Organization and the Atomic Energy Commission of the United Nations.

Fr´ed´ eric succeeded Ir `ene at the Sorbonne, while keeping his chair at the

Coll`ege de France, but on August 14, 1958 he too succumbed to radiation

sickness. He was also given a state funeral and was buried at Sceaux, next

to the grave of Ir `ene. Various memorials were dedicated to his memory in

France; the Soviet Union named one of its warships after him, also a mountain

that had just been climbed for the first time and a crater on the far side

of the moon, which had been observed by one of its satellites.

Enrico Fermi (1901–1954)

The Fermis came from a rich agricultural region near Piacenza, in the Po

valley of northern Italy. Stefano Fermi, Enrico’s grandfather, was the first

member of the family not to work the soil with his own hands. He had

obtained a modest position in the service of the duke of Parma, one of

a number of minor princes who ruled in the Po valley after Napoleon’s

downfall. The reactionary princelings were under strong Austrian influence,

but they seem to have been close to their subjects. At his death in 1905 at

the age of eighty-seven, Stefano owned a small house and some land in

Caorso, near Piacenza. His wife Giulia (n ´ee Beronzi) was an example of

the type of Italian countrywoman often described by nineteenth-century

Italian novelists. With a large family, she worked long hours in the home

and possessed all the domestic virtues. She could read but not write. She

was devoted to the church and brought up her children in the Catholic faith;

only Alberto, Enrico’s father, left it.

336 From de Broglie to Fermi

Alberto Fermi, the second son of Stefano, was born at Borgonure,

near Piacenza, in 1857. Probably he attended one of the technical high

schools which were instituted shortly after the unification of Italy. These

were intended to prepare young people of limited means for useful careers.

Certain private railway companies later taken over by the state employed

him in various supervisory and administrative capacities until, by the time

he retired in 1921, he was a divisional chief inspector of the Italian State

Railways. His wife Ida (n ´ee de Gattis) was born in the Adriatic city of Bari

in 1871. She was the daughter of an army officer and had studied electrical

engineering at university, after which she taught in elementary schools until

she married. She was fourteen years younger than her husband, unusually

intelligent and able. They were living in Rome when their three children

were born in successive years: Maria in 1899, then Giulio and finally Enrico,

on September 29, 1901.

As babies, all three were sent out to nurse in the country. Because

of his delicate health, Enrico did not return home until he was two and a

half years old. His mother taught him to read and write; soon he began to

show an unusual mathematical ability and a prodigious memory. At the

Enrico Fermi (1901–1954) 337

local high schools, first the ginnasio for five years, then the liceo for two

more, he was much the best pupil of his year, with an excellent scholastic

record. Because of the habits of order and discipline he had learned from his

mother, he enjoyed considerable free time, most of which he seems to have

devoted to scientific studies. In 1915 his parents were devastated when their

eldest son Giulio died in hospital before a minor operation.

While Enrico received encouragement in his studies from members

of the family, the influence of a colleague of his father’s, Adolfo Amidei,

was more important. Amidei lent him books on mathematics and, after

becoming convinced that he was a prodigy, advised him to apply to enter

the highly selective Scuola Normale Superiore in Pisa, the best place in the

country for physics. Fermi spent four years in Pisa studying the classics of

physics, works that he could quote almost verbatim years later. Because

he knew some French and German, he could also read the latest papers on

the subject. His exceptional abilities were soon recognized; he understood

the old quantum theory better than anyone else in Italy at the time. He also

proved competent in experimental work, although the physics laboratory of

the university was in a deplorable state of neglect. In 1922 Fermi obtained his

doctorate, and the following year wrote his first important research paper,

showing that, in the vicinity of a world line, space-time is Euclidean. This

impressed Tullio Levi-Civit` a, the main Italian relativist.

The post-doctoral career of a young scientist in Italy at this time often

began by his becoming an assistant to a professor and then obtaining the

libera docenza, the right to give lectures, equivalent to the venia legendi.

After a few years in this lowly state, the next stage was to apply for a professorship

in a national competition called a concorso; usually three of the

candidates were chosen and assigned to vacancies at different universities.

The candidates submitted publications, but influence was important too.

Subsequent promotion was usually by seniority, from one university to a

better. The ultimate accolade was election to the venerable Accademia dei

Lincei.

After Mussolini’s march on Rome in 1922, Fermi considered the possibility

of emigrating, but first he needed to establish a reputation outside

Italy. He won a fellowship for post-doctoral study in natural sciences offered

by the Italian Ministry of Education and used it to spend a year inGo¨ ttingen,

at the Institute where Born was professor of theoretical physics. Despite

receiving a warm welcome from the Borns, he did not enjoy the experience,

feeling isolated and foreign. The faculty, he found, assumed an attitude of

omniscience while, despite his quite adequate knowledge of German, he was

338 From de Broglie to Fermi

not welcomed into the group around Heisenberg and Pauli. Although they

became more friendly later, it meant that his year at the Georgia Augusta

was not as valuable as it might have been. When he returned from Germany

Fermi obtained a temporary position as assistant to Senator Orso Mario

Corbino, the senior physicist at the University of Rome. He was then

awarded a three-month fellowship from the International Education Board

to visit Leiden and work with Ehrenfest in 1924.

From his student years onwards Fermi used to return to the family

home whenever he could. His mother never really got over the loss of her

eldest son; she died in 1924, and his father died three years later. That left

only Enrico’s sister Maria; they lived together until 1928, when Enrico married.

His bride was Laura Capon, the daughter of a highly cultured and

respected family of non-observant Jews; her father was an admiral in the

Italian navy.

Fermi was obliged to publish in Italian, but he also published the

same work in German translation, to make it more accessible. Later, after

the Nazis had come to power, he published in English instead. The senior

Italian physicists had agreed on a scheme to provide junior positions for

their able youngsters, which resulted in Fermi going to Florence. When a

chair fell vacant at the University of Cagliari in Sardinia, Fermi applied for

it but was unsuccessful. However, the following year he entered a concorso,

which resulted in him being appointed professor of theoretical physics at

the University of Rome, a far more important post.

Now twenty-six, Fermi was determined to do all he could to modernize

the study of physics in Italy. He gave semi-popular lectures at the

annual meetings of the Italian Society for the Advancement of Science. At

the university the seminar he ran attracted many young physicists. One of

them was Ettore Majorana, a theoretician of outstanding ability, who later

mysteriously disappeared; he was excessively modest about his research

but the little he published has proved to be of great importance. Fermi also

wrote an Introduzione alla fisica atomica, which was published in 1928, and

with Corbino he set about strengthening the experimental side of physics

in Rome. Unfortunately Fermi antagonized the professor in charge of that

side, who had the power to block any reform. In 1929 Fermi was the only

physicist appointed to the new Accademia d’Italia, created by Mussolini to

replace the Lincei which he believed was too much a focus of opposition to

fascism. The appointment gave Fermi the title of Excellency and put him in

a better position to obtain support for his research, but the process of making

university appointments remained under the control of the old guard.

Enrico Fermi (1901–1954) 339

Fermi crossed the Atlantic for the first time during the summer of

1930, to collaborate with Ehrenfest in teaching during a summer school at

the University of Michigan. Someone who met him then described him as

‘a very young and pleasant little Italian, with unending good humour, and

a brilliant and clear method of presenting what he has to present in terrible

English’. This was such a success that he returned twice more and increasingly

came to appreciate the American way of life. On one such visit he

bought a car, named it ‘the flying tortoise’ and, when it broke down, Fermi,

who was a capable mechanic, repaired it in a garage so efficiently that the

manager offered him a job on the spot. In the summer of 1934 he went on

a lecture tour of South America sponsored by the Italian government, stopping

in London on the way back to report on the latest research of his team

in Rome at an international physics conference. They had been bombarding

all kinds of elements with neutrons and had found some puzzling results

in the case of uranium. The suggestion was made at the time that the uranium

nucleus was being split, but other interpretations seemed much more

likely. Some believe that this experimental work was the cause of the cancer

which led to Fermi’s death twenty years later.

By 1937 Fermi’s influence in Italy was on the wane. He was unsurprised

to find that he had not been chosen to succeed Corbino in Rome and

began to think more and more seriously about the possibility of emigrating

to the USA. The subjugation of Austria by Germany two years later was a

sign that Italy was powerless to stand in Hitler’s way. In 1938 Mussolini,

having signed the Italian–German alliance, promulgated the Manifesto della

razza, on the German model, which classified the Jews as aliens. The

racial laws did not affect Fermi or his two children directly, but his wife’s

family was Jewish and it was not clear what the consequences would be

for her.

Fermi had previously received offers of positions from several American

universities and he now decided that the time had come to follow these

up. Before long he had accepted an appointment to a chair at Columbia University

in New York City. Only a few people knew that he was leaving Italy

permanently; in order to avoid trouble with the fascist authorities it was necessary

for him to pretend that it was just another visit to America. Towards

the end of the year, he was awarded the Nobel prize in physics ‘for his

demonstrations of the existence of new radioactive elements produced by

neutron radiation, and for his related discovery of nuclear reactions brought

about by slow neutrons’. Shortly afterwards the family left for Stockholm

to attend the Nobel ceremonies and then went to Copenhagen to spend a

340 From de Broglie to Fermi

few days with Bohr, before sailing for New York. Once Fermi had made a

decision he never looked back.

Like his father, Fermi’s nature was that of a loyal and efficient public

servant. In his last years in Italy he had served in a few high-level advisory

posts in the Ministry of Education and as consultant for a few industrial

firms, but he avoided controversy. His interests outside science were rather

limited. Physically he was strong and had plenty of stamina. He was, after

all, of peasant stock. He would challenge younger physicists to play tennis

in the heat of a New York summer day and, after an exhausting hour or

so under the broiling sun, would remark on their lack of vigour. When he

lectured, he did so with a strong Italian accent.

In 1939 Fermi was at the midpoint of his career and about to become

involved in events he could hardly have foreseen. The news of the discovery

of nuclear fission, brought to America by Bohr, reached him soon after

he had landed in New York. Then Germany invaded Poland and the Second

WorldWar began, although the USA was not a participant until later. At first

the development of radar had top priority among leading scientific administrators

in the USA; research into atomic energy received no more than the

ordinary level of support. Fermi was concerned about this and, together with

the ´emigr´e Hungarian physicists Leo Szilard and Eugene Wigner, drafted an

important letter for Einstein to send to President Roosevelt pointing out

the dangerous military potentialities offered by nuclear fission and warning

him that Germany might be developing these weapons. This letter helped

to initiate the American efforts that eventually produced the nuclear reactor

and the fission bomb. Until there was a change of research priorities, a

large proportion of the physicists involved in America’s earliest efforts to

release nuclear energy came from Europe, and Fermi was one of them.

The first step was to try to produce a chain reaction. Work on this

project was concentrated in Chicago but ironically Fermi, being an enemy

alien, was confined to New York, and his mail was subject to censorship.

However, in 1942 Roosevelt announced that Italians would no longer be

considered enemy aliens, and Fermi was able to join the other scientists

working in Chicago, although his mail was still being censored. One of the

other physicists involved described how Fermi played a leading part in the

work:

Fermi possessed a sure way of starting off in the right direction, of

setting aside the irrelevances, of seizing all the essentials and

proceeding to the core of the matter. The whole process of wresting

Enrico Fermi (1901–1954) 341

from nature her secrets was for Fermi an exciting sport which he

entered into with supreme confidence and great zest. No task was too

menial if it sped him towards his goal. He thoroughly enjoyed the

whole of the enterprise. The piling of the graphite bricks, the running

with the short-lived rhodium foils, and the merry clicking of the

Geiger counter which effected the measurement, all was done with

great energy and with obvious pleasure, but by the end of the day, in

accordance with his plan, the results were neatly compiled, their

significance assessed, and the progress measured, so that early in the

morning of the following day the next step could begin.

It was a feature of the Fermi approach never to waste time – to keep

things as simple as possible, never to construct more elaborately or to measure

with more care than was required by the task at hand. In such matters

his judgement was unerring. In this way, step by step, the work sped forwards

until, in less than four short years, Fermi had reached his goal. A

huge pile of graphite and uranium had arisen in the football stadium of the

University of Chicago. When Fermi stood before that silent monster, he

was its acknowledged master. Whatever he commanded it obeyed. When

he called for it to come alive and pour forth its neutrons, it responded with

remarkable alacrity; and when at his command it quietened down again, it

had become clear to all who watched that Fermi had indeed unlocked the

door to the neutron. Early in the afternoon of December 2, 1942, the chain

reaction was demonstrated successfully.

Soon further research on the project was transferred to the Los Alamos

National Laboratory, where Fermi became a sort of oracle to any physicist in

trouble, as was the ´emigr´e Hungarian mathematician von Neumann. Three

years later the war in Europe was over, and the race to develop the atomic

bomb before the Germans could do so had been won decisively. Although

some of the other physicists on the project remained at Los Alamos, Fermi

decided to return to normal academic work. He accepted the offer of a professorship

at the University of Chicago, which was developing a promising

science programme. The teaching aspect of the position appealed to

him very much, as did the experimental facilities at the Argonne National

Laboratory, including the powerful cyclotron. He served as president of the

American Physical Society and helped to defend Oppenheimer at the notorious

security-clearance hearing, of which more later.

Fermi liked to spend the summer away from the university, but at first

only within the USA. It was not until 1949 that he returned to Europe and,

342 From de Broglie to Fermi

after attending some important conferences, went back to his homeland for

the first time since 1938. The new generation of physicists who had emerged

in Italy after his departure saw and heard the almost-legendary Fermi.

In the summer of 1954 he made what proved to be his last visit to

Europe. His health was failing; an insidious illness had attacked him and

resisted diagnosis. With great strength of will he tried to carry on as before,

but, when the disease was finally diagnosed, it proved to be incurable, caused

by a malignant stomach tumour. He died on November 28, 1954 in Chicago,

just after his fifty-third birthday, survived by his wife Laura and their two

children. There is a memorial in the Florentine church of Santa Croce, alongside

those in honour of other great Italian scientists.


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