November 28, 1954 – Death of Enrico Fermi, the Nobel Prize winner who achieved the first nuclear chain reaction

Prolific scientist who has gone down in history for being the first to carry out self-sustaining nuclear fission and for having devised the first mathematical method capable of describing the behavior of certain types of subatomic particles.

In 1938, he was awarded the Nobel Prize in Physics for demonstrating the existence of new radioactive elements produced by neutron irradiation and for the discovery of nuclear reactions by slow neutron bombardment.

Consecrated as one of the great promises of Italian science, he received a grant from the government so that he could study at the University of Göttingen (Germany), considered at that time the focus of world Physics research. There he expanded his knowledge with Max Born, one of the greatest scientists of quantum mechanics..

In 1924, he received a scholarship from the Rockefeller Foundation to study at the University of Leiden (The Netherlands) where he continued his research in the field of Nuclear Physics, laying the foundations for his great discoveries. That same year, he returned to Italy and began his career as a professor at the University of Florence, where he began to acquire prestige and celebrity, especially after enunciating, in 1926, the so-called "Fermi-Dirac Statistics", basically a set of quantum laws and measurements that showed that subatomic particles are governed according to Ernest Paulí's exclusion principle.

Over time, the importance of these works on quantum statistics led to these particles being called fermions, in contrast to the bosons of the so-called "Bose-Einstein Statistics".

In 1927, he received the chair of Theoretical Physics at the University of Rome, although he did not stop traveling to all the places where the main advances in Physics of his time were being forged. For this reason, in 1930, he began to teach summer courses at the University of Michigan (United States). This leads him to teach courses and conferences at the universities of Columbia, Stanford and Chicago.

In 1933, he published his theory of beta radioactive decay, according to which a neutron emits an electron (ß particle) and an antineutrino to become a proton. Shortly after, after the discovery of the neutron by James Chadwick, the Joliot-Curie couple found artificial radioactivity and were able to form new isotopes by bombarding various substances with alpha particles. Fermi reflected on both findings and deduced that the neutron, lacking an electric charge, could be a more suitable projectile than alpha particles to carry out this type of bombardment; He then went on to the experimental phase and, using slow neutrons that he had managed to stop with paraffin, he bombarded sixty chemical elements, with which he was able to generate forty new isotopes.

During that decade, he not only disseminated his knowledge in the United States, but also in Europe and South America, which allowed him to surround himself with a team of great collaborators with whom he was able to analyze in depth the delay experienced by the neutron (another particle that had just discovered) in the hydrogenated materials. In addition, he carried out an extensive study of a large number of artificially radioactive substances, all produced by the capture of slow neutrons by atomic nuclei, obtaining a series of important data on radioactivity such as the discovery of nuclear reactions by bombardment with slow neutrons. , which led him to receive, at the age of 40, the Nobel Prize in Physics in 1938.

In 1939, due to the political situation in Italy, he decided to emigrate to the United States, where he was a Physics professor at the prestigious Columbia University (New York). It is there that he received the news of the discovery of uranium fission by Otto Hahn and Friedrich Strassman, and began to study it in depth, because he saw the possibility of achieving the emission of secondary neutrons and thus giving rise to a chain reaction. .

Surrounded by his new team made up of more than 40 scientists, he managed to manufacture the first nuclear reactor, called Chicago Pile-1, with which on December 2, 1942, in a laboratory at the University of Chicago, he managed to produce the first nuclear reaction. in a chain subject to the control of the one who triggered it.

If you want to know more about this scientist, click on the following link: Enrico Fermi