29 September 2017

Enrico Fermi – nuclear physicist

Scientist from Rome who created world’s first nuclear reactor

Enrico Fermi discovered how splitting uranium atoms could generate vast amounts of energy
Enrico Fermi discovered how splitting uranium
atoms could generate vast amounts of energy
Enrico Fermi, who has been called the architect of the nuclear age and even the father of the atomic bomb, was born on this day in 1901 in Rome.

Fermi, who won a Nobel Prize in 1938, created the world’s first nuclear reactor, the so-called Chicago Pile-1, after he had settled in the United States, and also worked on the Manhattan Project, which was the code name for the secret US research project aimed at developing nuclear weapons in the Second World War.

The third child of Alberto Fermi, an official in Italy’s Ministry of Railways, and Ida de Gattis, a school teacher, Fermi took an interest in science from an early age, inspired by a book about physics he had discovered in the local market in Campo de’ Fiori in Rome, written in Latin by a Jesuit priest in about 1840.

He read avidly as he was growing up, conducting many experiments. After high school, he was granted a place at the prestigious Scuola Normale Superiore, part of the University of Pisa, where it became clear the depth of knowledge he had already acquired was greater than that of many of his professors. It was not long before they began asking him to organise seminars in quantum physics. He graduated with honours in 1922.

After spending several months in Germany and Holland on scholarships, working alongside renowned professors such as  Max Born and Paul Ehrenfest, he returned to Italy to take up a lectureship at the University of Florence. In 1927 he was appointed Professor of Theoretical Physics at the University of Rome.

Fermi (centre), with his fellow scientists at the University of Pisa, Franco Rasetti and Emilio Segrè
Fermi (centre), with his fellow scientists at the University of
Pisa, Franco Rasetti and Emilio Segrè
In the same year, he married Laura Capon, who came from a respected Jewish family in Rome.  They would soon have two children, Giulio and Nella.

In 1934, Fermi began working with the atom, the area of physics that would define his life. He discovered that nuclear transformation could occur in nearly every element.

One of the elements whose atoms he split was uranium. This led to discovery of slow neutrons, which in turn led to nuclear fission and the production of new elements.

When, in 1938, Fermi was awarded the Nobel Prize in Physics "for his work with artificial radioactivity produced by neutrons, and for nuclear reactions brought about by slow neutrons”, it could not have come at a more timely moment.

Benito Mussolini, whose Fascist party Fermi had joined when he was made a member of the Royal Academy of Italy in 1929, had introduced tough new race laws in his support for the German leader Adolf Hitler. The anti-Jewish element of these laws threatened Fermi’s family and he became desperate to leave Italy.

The eerie mushroom cloud formed by the  first test explosion of an atomic bomb
The eerie mushroom cloud formed by the
first test explosion of an atomic bomb
Strict travel restrictions were being implemented, too, but Mussolini wanted Fermi to receive his Nobel award in person at the ceremony in Sweden and allowed him to travel with his family. Once in Stockholm, they made arrangements to escape to America.

Thus Fermi, his wife and their children disembarked a passenger liner in New York in January 1939.  He quickly settled into an academic career in American universities.

Fermi was appointed professor of physics at New York's Columbia University, where he discovered that if uranium neutrons were emitted into fissioning uranium, they could split other uranium atoms, setting off a chain reaction that would release enormous amounts of energy. His experiments led to the first controlled nuclear chain reaction, which he prosaically christened Chicago Pile-1, on December 2, 1942, under Chicago University's athletic stadium.

During the Second World War, Fermi was invited to join the Manhattan Project, which focused on the development of the atomic bomb. Worried that scientists in Germany were close to developing their own bomb, Fermi and other scientists encouraged the US Government to invest in the project without delay.

He witnessed the first test detonation of a nuclear weapon, codenamed Trinity, in a remote area of desert in New Mexico on July 16, 1945.  He advised the US Government on target selection, recommending the bomb be used without warning against an industrial area.

General Leslie R Groves presents Fermi with his Medal of Merit for wartime service to the US
General Leslie R Groves presents Fermi with his
Medal of Merit for wartime service to the US 
After the war, Enrico Fermi was appointed to the General Advisory Committee for the Atomic Energy Commission. In October 1949, the commission met to discuss the development of the hydrogen bomb, a weapon 500 times more powerful than the atomic bombs dropped on Hiroshima and Nagasaki in Japan, which themselves killed 129,000 people.

Fermi was appalled at the prospect, however, opposing it on both technical and moral grounds.

In 1944, Fermi and his wife had become American citizens, and at the end of the war he accepted a professorship at the University of Chicago's Institute for Nuclear Studies, a position which he held until his death. There he turned his attention to high-energy physics, and led investigations into the pion-nucleon interaction.

He died in 1954 at the age of only 53 from stomach cancer. It is thought likely now that he developed the disease as a result of his exposure to radiation, possibly when he witnessed the Trinity explosion, when he reported feeling the heat from the blast, or from his work creating the Chicago reactor.

He confessed to friends during his life that he was aware that he might be at risk but considered scientific advancement more important than his own long-term health.

As well as his Nobel prize, Fermi won many other awards for his research, while others granted to modern scientists bear his name.  Among other things named after him are the Fermilab particle accelerator and physics lab in Batavia, Illinois and the Fermi Gamma-ray Space Telescope.  Three nuclear reactor installations have been named after him: the Fermi 1 and Fermi 2 nuclear power plants in Newport, Michigan, the Enrico Fermi Nuclear Power Plant at Trino Vercellese in Italy, and the RA-1 Enrico Fermi research reactor in Argentina.

A synthetic element isolated from the debris of the 1952 Ivy Mike nuclear test was named fermium, in honour of Fermi's contributions to the scientific community.

The Basilica of Santa Croce in Florence, known as the Temple of Italian Glories for its many graves of artists, scientists and prominent figures in Italian history, has a plaque commemorating Fermi.

Fermi's birthplace in Via Gaeta in Rome
Fermi's birthplace in Via Gaeta in Rome
Travel tip:

Fermi’s birthplace in Rome was in Via Gaeta, not far from the Termini railway station, and the house is marked with a plaque. The area around Via Gaeta has nothing in particular to recommend it but nearby are the ruins of the Terme di Diocleziano – the Baths of Diocletian – a Roman bathing complex that covered 13 acres and could accommodate up to 3,000 people. The complex today houses one of the four sites of the Museo Nazionale Romana, containing a fascinating collection of objects and artefacts to help visitors build a picture of Roman life in the days of the empire. Also worth visiting at the site is a large and peaceful cloister built from designs by Michelangelo.

The magnificent Basilica of Santa Croce in Florence
The magnificent Basilica of Santa Croce in Florence
Travel tip:

The Basilica of Santa Croce, with its 16 chapels, is the largest Franciscan church in the world, and has been one of Florence’s most impressive buildings since it was completed towards the end of the 14th century. Inside can be found work by many of the great artists of the Renaissance, including Giotto, Cimabue, Donatello, Antonio Canova and Domenico Veneziano. The Basilica is also notable as the burial place of a host of illustrious Italians, such as Michelangelo, Galileo, Machiavelli, the poet Ugo Foscolo, the philosopher Giovanni Gentile and the composer Rossini.

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