Science Library - free educational site

Enrico Fermi

1901 - 1954

Enrico Fermi, 1901-54, Italian physicist and pioneer of nuclear physics

Enrico Fermi was of the most prominent physicists of the first half of the twentieth century, and a pioneer of nuclear physics.

  • Nationality
  • Italian

  • Subject
  • Physics, Nuclear

  • Fields
  • Quantum Theory, Particle Physics, Statistical Mechanics

  • Distinctions
  • Nobel Prize for Physics, 1938, for his work on induced radioactivity by neutron bombardment, and the discovery of transuranic elements (elements with atomic numbers greater than 92).

    Fermi was awarded many prizes and awards for his pioneering work, as well as American honours for his contribution to his contributions to the Manhatten Project: including the Max Planck Medal (1954), Rumford Prize (1953), Foreign Member of the Royal Society (1950), and the Matteucci Medal (1926).

    He is referred to as the 'architect of the nuclear age'.

    Fermi's name is used as an appellation for many institutes and other scientific organisations, including the Enrico Fermi Award (lifetime achievement in the development, use, or production of energy), Enrico Fermi Institute (University of Chicago), Fermilab (Fermi National Accelerator Laboratory, specialising in high-energy particle physics, Batavia, Illinois), Fermi Gamma-ray Space Telescope (launched June 11 2008), and the Enrico Fermi Nuclear Generating Station (Michigan).

    The element "fermium" (Z = 100) is named after him.

  • Posts
  • Director of the team which built the first reactor: Chicago Pile-1 in 1942.

    Key role in subsequent Manhatten Project developments, including the X-10 Graphite Reactor at Oak ridge, Tennessee (1943) and the B Reactor at Hanford.

    Director of "F Division", which worked on the Teller thermonuclear bomb design. He was present at the Trinity Test on 16 July 1945.

    General Advisory Committee member under Robert Oppenheimer, which advised the US Atomic Energy Commission on nuclear policy.

    Fermi studied in Germany and Holland in 1924, before returning to Italy, where he taught and researched at various universities before taking up the newly created professorship at the Sapienza University of Rome, 1926.

  • Publications
  • Sulla dinamica di un sistema rigido di cariche elettriche in moto traslatorio, (On the dynamics of a rigid system of electrical charges in translational motion) 1921, Fermi's first paper for the journal Nuovo Cimento. In this paper, Fermi applies relativity to the calculation of the mass of an electrically charged particle, a theme he followed up in a subsequent paper Concerning a contradiction between electrodynamic and the relativistic theory of electromagnetic mass, which was translated and published in Physikalische Zeitschrift in 1922.

    Sull'elettrostatica di un campo gravitazionale uniforme e sul peso delle masse elettromagnetiche, (On the electrostatics of a uniform gravitational field of electromagnetic charges and on the weight of electromagnetic charges) 1921, Fermi's second paper for the journal Nuovo Cimento. Fermi applies general relativity to the electrostatic energy of a system of charges.

    Sulla quantizzazione del gas perfetto monoatomico, (On the quantisation of the perfect monoatomic gas), 1925, a paper inspired by Wolfgand Pauli's Exclusion Principle. In this paper Fermi applies the principle to an ideal gas.

    Introduzione alla fisica atomica, (Introduction to Atomic Physics), 1928, a university textbook.

    Über die Wechselwirkung von Zwei Elektronen, (On the Interaction between Two Electrons), 1932, written with Hans Bethe.

  • Laws
  • Fermi-Dirac statistics: a statistical formulation describing the distribution of particles in adherence to Pauli's Exclusion Principle, also developed by Paul Dirac, and in the Bose-Einstein statistics.

    Fermi postulated the existence of the fourth fundamental force of nature: weak nuclear force.

    Principle of Equivalence, involving Fermi coordinates: on a world line close to the time line, space behaves as Euclidean Space.

  • Theories
  • Quantum Theory

    Nuclear Physics: explanation of beta decay, postulation of the existence of the neutrino.

    Particle Physics: Fermi's interaction, later named weak force.

    Statistical Mechanics: Pauli applied Pauli's Exclusion Principle to an ideal gas. This led to a new classification of particles: those which obey the exclusion principle are called "fermions", while those that do not are called "bosons".

  • Equations
  • Fermi age equation, a diffusion equation which describes the capturing of neutrons by nuclei, establishing the principle that slow neutrons are more easily captured.

  • Experiments/Discoveries
  • Fermi was an early user of neutron bombardment to induce radioactive emissions in various elements, and discovered that a neutron may decay into a proton, ejecting an electron as beta radiation.

    Fermi built the world's first nuclear reactor: Chicago Pile-1, in 1942, to test the theoretical calculation of the critical mass of uranium.

    Fermi method: used to estimate a nuclear bomb's yield (first applied to the Trinity Test, 16 July 1945.

Enrico Fermi, 1901-54, Italian physicist and pioneer of nuclear physics

Fermi was publishing ground-breaking papers already at the age of 20, and received his degree at, for those times, the very young age of 21. He was unusually equally skilled in theoretical and experimental physics. In 1923, Fermi was the first to publish the realisation that Einstein's $E = mc^2$ promised the enormous potential of nuclear energy.

During 1924, Fermi travelled and worked for 6 months in Germany, at the University of Göttingen. Here, he met Max Born, Werner Heisenberg, and Pascual Jordan. Then at Leiden, Holland, he met Paul Ehrenfest, Henrik Lorentz and Albert Einstein.

After travelling to Sweden in 1938 to receive his Nobel Prize, Fermi decided not to return to Italy, so his jewish wife could escape fascist persecution. They emigrated to the USA, where he became a citizen in 1944. In America, he was central to the development of the atomic bomb (Manhatten Project), as part of which he developed the first nuclear pile reactors.

Chicago Pile-1, the first nuclear reactor
Chicago Pile-1, the first nuclear reactor, 1942

Like many of his fellow scientists, Fermi participated in the development of the nuclear bomb during World War Two, but after the war opposed the proliferation of nuclear weapons.

Fermi died of stomach cancer at the age of 53.

Choose a subject for more biographies