The life of the scientist

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Enrico Fermi’s life
(1901-1954)
Fermi’s youth
Enrico Fermi was born on September 29, 1901 in Rome, to Alberto
and Ida De Gattis. His father was Chief Inspector of the Italian
railways company, while his mother was a school teacher. From
their marriage, three sons were born: Maria in 1899, Giulio in 1900
and Enrico.
The best (and almost only) friend of the
young Enrico was his brother Giulio, with
whom he attended the first school years. At school, Enrico
was a good student, with only some problems with writing in Italian.
In 1915, a tragic event upset the lighthearted life of Enrico and his
family: his brother Giulio died as a consequence of a surgery. Enrico
tried to overcome such a deep sorrow by studying scientific
arguments extensively .
Fortunately, soon after he established a close friendship with
a friend of his brother Giulio, namely Enrico Perisco,
sharing many interests with him, including physics. In this
period, they measured autonomously the density of a
particular drinking water (Acqua Marcia), the free fall
acceleration and the magnetic field of the Earth.
Fermi was not a “nerd,” or a bookworm, inclined to spend all his time studying. He was
active in sports and very competitive. Fermi was also orderly in his work habits, so he had
time left over after his schoolwork for independent reading, especially in science. Indeed,
Fermi’s interest in mathematics and physics manifested itself very early. From
the end of 1914 till 1918, he was guided in his studies by a friend of his father,
the engineer Adolfo Amidei, who frequently lended him advanced
(universitary level) books of physics and mathematics. He found these books
“very interesting, useful and not at all hard to understand”. In July 1918, skipping his last
school year, he finished his high school studies and received his diploma (licenza liceale).
Then, Enrico decided to study Physics at the
university and, upon suggestion of the engineer
Amidei, he moved to Pisa, to the prestigious
Scuola Normale Superiore (founded by
Napoleon in 1813), after he easily and
brilliantly passed the admission examination
(“a boy with extraordinary talents”).
Fermi conducted his studies at Pisa very independently.
He soon found a friend and soul mate, a student at the
university named Franco Rasetti. Like Fermi, Rasetti
was very interested in science; and was so good at his
college studies that there was time left over for hikes in
the coastal mountains.
The studies at the Scuola Normale proceeded brilliantly; he always
obtained the highest possible grades, except in drawing and in some
chemistry courses. He enjoyed enormous prestige among his fellow
students and his superior ability was recognized by everybody.
Fermi and Rasetti soon had the run of the
undergraduate laboratory, because the elderly
professor in charge (Luigi Puccianti) could no
longer keep up with the rapidly expanding field of modern physics.
In fact, he turned the tables and asked Fermi to teach him about the
theory of relativity, developed by the German theoretical physicist
Albert Einstein.
By the fall of 1920, the end of his sophomore year,
Fermi had completed all of the standard courses and
was able to take advantage of a very special
opportunity. Once again, Fermi and Rasetti had free
access to the graduate research laboratory as they once
had in the teaching lab. Fermi chose to do experiments
with X rays and made that the subject of the dissertation
required for his doctoral degree at the university.
Enrico Fermi received his Ph.D. degree in physics from the University of Pisa in July of
1922 and a diploma certifying to his status as a graduate of the Scuola Normale Superiore at
the same time.
Studying abroad
Just after his graduation, during the winter 1922-3 Fermi won a
scholarship from the Ministero dell’Istruzione Pubblica to study abroad.
He chose to work with the great physicict Max Born at the University of
Göttingen, where he built a center for theoretical physics, researching on
the novel quantum physics, that attracted brilliant postdoctoral students
from abroad. However, Fermi did not profit very much from his stay there.
Instead, the subsequent months were more fruitful,
when in 1924 Fermi moved to Leyden (Holland)
with a Rockfeller
Fellowshipn to work
with the Dutch
physicist Paul Ehrenfest.
This was one of the
greatest teachers of
physics and a man of
warm human interests.
He appreciated Fermi’s special talents, and his praise was an
important boost for a young postdoctoral student still at the
beginning of his career.
Back to Italy
When he returned to Italy in 1924, Fermi began
teaching at the University of Rome and then, in
1925, he moved to the University of Florence,
where he found his friend Franco Rasetti.
Fermi and Rasetti made a great team. They could
share ideas for experiments and discuss the articles in
the latest physics journals from abroad. Fermi took the
lead when it came to discussing theory, while Rasetti was able to refine Fermi’s
experimental technique using his own strong instincts as a creative experimenter.
The Florentine period saw Fermi’s first major
contribution to theoretical physics: the discovery
of the statistical laws (Fermi-Dirac statistics)
which govern particles subject to Pauli’s
exclusion principle (such as, for example,
electrons, protons, neutrons, etc.).
These particles are called today fermions.
P.A.M. Dirac
W. Pauli
The period in Rome and the“Panisperna boys”
After Fermi returned from abroad to Rome, he became
acquainted with Senator Orso Mario Corbino, Professor
of experimental physics and Director of the Institute of
Physics at the University of Rome. Although completely
absorbed in politics and business, Corbino was the most
open-mined among all Italian physicists in a position of
authority.
Fermi and Corbino had met several times before Fermi
went to Germany, and Corbino had been very impressed.
He had grasped that Fermi was the right person to bring the
revolution in physics, already underway elsewhere in
Europe, into the classrooms and research laboratories of his
native country.
The breakthrough came in 1926. Corbino was able to obtain a chair in theoretical
physics, the first in Italy, established in Rome, and the Board of Examiners
unanimously agreed that Fermi was the outstanding candidate. “They felt they could
rest on him the best hopes for the affirmation and future development of theoretical
physics in Italy.”
In the fall of 1926 Fermi then moved to
Rome (Enrico Persico replaced him at
Florence), and at the Physics Institute
of Via Panisperna 89a he started one of the most fruitful periods of
his scientific career.
In Rome Fermi felt a strong urge to find an adequate scientific
environment. He and his mentor Corbino then began a threepronged approach. First, Corbino convinced at least a few graduate
students at the University of Rome (from the Faculty of
Engineering) to learn modern physics. Second, Fermi started a
program of experiments and researches in the new physics. And
third, he wanted to propagandize for the revolution: to give
popular lectures, write articles, and do one further thing that was
new in Italy: write a textbook on modern, atomic physics.
Fermi knew the man he wanted to start building a program of
experiments in atomic physics. It was Franco Rasetti, his friend from
their student days in Pisa. Once again, then, Corbino attended to the
politics and; early in 1927, he arranged for Rasetti to move from
Florence (where he was working) to Rome: he was appointed as
Corbino’s first assistant. It was a good choice: Fermi could deepen
Rasetti’s understanding of the new quantum theories of the atom, while
Rasetti could continue to bring Fermi into flower as an experimentalist.
Recruiting graduate students proved a bit more difficult. During 1927
Corbino launched a famous appeal to the students
of the engineering faculty to entice the most brilliant young
minds into studying physics.
E. Segrè and his friend E. Amaldi rose to the challenge, and
joined Rasetti and students Amaldi and Segrè, the beginnings
of a modern-physics group had been assembled.Still others
soon joined Fermi and Rasetti’s group.
The group went on with its famous experiments, but in 1933
Rasetti left Italy for Canada and United States, Pontecorvo
went to France and Segrè left to teach in Palermo.
The most significant personal events of this period were
Fermi’s marriage to Laura Capon, and his appointment
by Prime Minister B. Mussolini to the Accademia
d’Italia. This honor, though well deserved, was
unexpected because Fermi’s reputation at the time was
limited to physicists and, according to tradition, at his
young age,academic honors were yet not due.The
appointment came mainly due at the instigation of
Senator Corbino.
Nobel Prize in Physics
The scientific work done at the Institute of Physics in Rome in those years was a very
remarkable contribution to the development of physics worldwide. These results earned
Enrico Fermi the Nobel Prize in 1938.
Unfortunately, in the autumn of 1938
the anti-semitic movement in Italy,
which developed after the ItalianGerman alliance, made Fermi decide
to leave Italy to accept a professorship
in U.S.A.. Indeed, his wife was
Jewish, and no guarantee of protection
from the new laws could be believed.
Recognizing the occasion of his family's travel to Stockholm for the
Nobel awards ceremony in 1938 as an
opportunity for escape, Fermi and his
family departed for the United States from the ceremony, after
a short visit to Niels Bohr in Copenhagen, on December 24.
Fermi was then in the middle of his career, and could not
have expected to be involved so soon in historical and
scientific events of the greatest moment, events that were the
direct result of those researches developed in Rome.
The American period
Soon after his arrival in New York, Fermi
began working at Columbia University.
On 25 January 1939, a Columbia
University team conducted the first nuclear
fission experiment in the United States,
which was done in the basement of Pupin
Hall; the members of the team were
Herbert L. Anderson, Eugene T. Booth,
John R. Dunning, Enrico Fermi, G. Norris
Glasoe, and Francis G. Slack.
Fermi then went to the University of
Chicago and began studies that led to the
construction of the first nuclear pile
Chicago Pile.
This experiment was a landmark in the quest for energy, and it was typical of Fermi's
brilliance. Every step had been carefully planned, every calculation meticulously done
by him. This successful initiation of a chain-reacting pile was important not only for its
help in assessing the properties of fission — needed for understanding the internal
workings of an atomic bomb — but also because it would serve as a pilot plant for the
massive reactors which would be created in Hanford, Washington, which would then be
used to produce the plutonium needed for the bombs used at the Trinity site and
Nagasaki. Eventually Fermi and Szilárd's reactor work was folded into the Manhattan
Project.
Fermi moved to Los Alamos in the later stages of the
Manhattan Project to serve as a general consultant. He was
sitting in the control room of the Hanford B Reactor when it
first went critical in 1944. His broad knowledge of many fields
of physics was useful in solving problems that were of an
interdisciplinary nature.
Having satisfied the residence requirements, the Fermis
had become American citizens in 1944. In 1946 he became
Distinguished-Service Professor for Nuclear Studies at the
University of Chicago and also received the Congressional
Medal of Merit. At the Metallurgical Laboratory of the
University of Chicago, Fermi continued his studies of the
basic properties of nuclear particles, with particular
emphasis on mesons, which are the quantized form of the
force that holds the nucleus together. He also was a
consultant in the construction of the synchrocyclotron, a
large particle accelerator at the University of Chicago. In
1950 he was elected a foreign member of the Royal
Society of London.
In his later years, Fermi did important work in particle physics, especially related to
pions and mouns. He was also known to be an inspiring teacher at the University of
Chicago, and was known for his attention to detail, simplicity, and careful
preparation for a lecture.
In 1952, Fermi was elected President of the American Physical Society. On
November 16, 1954, President Eisenhower presented the Atomic Energy
Commission’s special award for his lifetime of accomplishments in physics and in
particular for the development of atomic energy.
Fermi died on November 28, 1954 in Chicago, just after his fifty-third birthday at
age 53 of stomach cancer and was interred at Oak Woods Cemetery in Chicago,
Illinois. Two of his graduate students who assisted him in working on or near the
nuclear pile also died of cancer. Fermi and his team knew that such work carried
considerable risk but they considered the outcome so vital that they forged ahead
with little regard for their own personal safety.
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