Enrico Fermi

How to use this course

Enrico Fermi is remembered in physics through a long list of words: fermion, Fermi energy, Fermi surface, Fermi’s golden rule, the Fermi constant, the Fermi age, the fermi as a unit of length, and Fermi problems. Each records a piece of physics he created or made usable. He was also the leader of the team that built the first nuclear reactor, and one of the founders of particle physics after the war.

Each technical lesson opens with a paragraph for the general reader, then gives precise statements, derivations and exercises with folded solutions. The lessons follow the chronology of his work: quantum statistics (1926), weak interactions (1933–34), neutron physics (1934–38), the chain reaction (1939–42), and pion physics and computation (1949–1955). Lesson 08 is about a habit of mind and runs across his whole career.

Timeline

Rome, 1901–1918

Enrico Fermi was born in Rome on 29 September 1901. His father, Alberto Fermi, was a division head in the Ministry of Railways; his mother, Ida de Gattis, taught elementary school. He was the youngest of three children. He and his brother Giulio, a year older, were inseparable and built electric motors together.

Giulio died in January 1915 during an operation on a throat abscess. Enrico was 14. He coped by throwing himself into study. In a Roman street market he bought a 900-page Latin treatise, Elementorum physicae mathematicae, by the Jesuit Andrea Caraffa, and worked through its mathematics, mechanics, astronomy, optics and acoustics. A school friend, Enrico Persico, shared his projects; together they studied the motion of gyroscopes. Persico later became a professor of theoretical physics himself.

A colleague of his father, the engineer Adolfo Amidei, noticed the boy’s talent, judged him a prodigy at least in geometry, and lent him a sequence of books on projective geometry, calculus, analytical mechanics and mathematical physics. Amidei also advised him to aim for the Scuola Normale Superiore in Pisa rather than the University of Rome. Fermi finished secondary school in July 1918, having skipped a year.

On 14 November 1918 he sat the Normale’s entrance examination. The set theme was the characteristics of sound. Fermi wrote down the partial differential equation of a vibrating rod and solved it by Fourier analysis. The examiner said the essay would have done credit to a doctoral candidate. He took first place.

Pisa, Göttingen, Leiden, Florence, 1918–1926

At Pisa, Fermi found that he knew more modern physics than his teachers. His nominal supervisor, Luigi Puccianti, asked him to explain relativity and quantum theory to the department. With a fellow student, Franco Rasetti, he played pranks and studied X-rays; the two became lifelong friends and collaborators. He published his first papers in Il Nuovo Cimento in 1921. A paper of 1922 introduced coordinates in which spacetime looks flat along an entire geodesic, not only at a point. These Fermi coordinates are still used in general relativity.

He graduated on 7 July 1922, magna cum laude. His work for the degree combined an experimental study of image formation with X-rays and a theoretical essay on a theorem of probability theory. He was 20.

Göttingen and Leiden

A government scholarship took him to Göttingen in the first half of 1923, where he worked in Max Born’s group alongside Werner Heisenberg and Pascual Jordan. He felt somewhat isolated there. In the autumn of 1924 a Rockefeller fellowship took him to Leiden, where Paul Ehrenfest received him warmly, and his encouragement restored Fermi’s confidence.

Florence

From January 1925 to late 1926 Fermi taught mathematical physics and mechanics at the University of Florence, where he and Rasetti also did experiments on the effect of radio-frequency fields on atomic spectra. He narrowly lost a competition for a chair at Cagliari. In Florence he read Wolfgang Pauli’s exclusion principle and saw at once that it answered a question he had been working on for two years: how to quantize an ideal gas. Lesson 04 tells that story.

The Rome school, 1926–1938

Orso Mario Corbino, director of the Physics Institute in Via Panisperna, senator and former minister, wanted to bring Italian physics into the quantum age. He persuaded the university to create one of the first three chairs of theoretical physics in Italy, and chaired the committee that chose Fermi for it in 1926, ahead of Persico and Aldo Pontremoli. Fermi was 25.

Corbino and Fermi recruited students. Rasetti came from Florence. Emilio Segrè and Edoardo Amaldi switched from engineering. Ettore Majorana, the most brilliant of them, joined in 1928, and Bruno Pontecorvo in the early 1930s. The chemist Oscar D’Agostino completed the group known as the Via Panisperna boys. Their nicknames were ecclesiastical: Fermi was the Pope, because he was infallible.

In 1927 Fermi produced a statistical model of the atom, treating the electrons as a degenerate Fermi gas in the self-consistent potential of the nucleus; Llewellyn Thomas had found the same model independently. His 1928 textbook Introduzione alla fisica atomica was the first in Italian on the new physics. On 19 July 1928 he married Laura Capon, a science student from a Jewish Roman family; their children Nella and Giulio were born in 1931 and 1936. On 18 March 1929 Benito Mussolini appointed him to the new Royal Academy of Italy, and he joined the Fascist Party the same year.

Fermi’s work in Rome runs from pure theory to pure experiment. The quantum electrodynamics lectures he gave at Ann Arbor in 1930 taught a generation. Then, in 1933, came the theory of beta decay (Lesson 05), and in 1934 he turned the whole group toward the neutron (Lesson 06). By 1938 the racial laws of Fascist Italy threatened his wife and several of his collaborators. Lesson 11 continues the story.

Fermi–Dirac statistics

For the general reader. Electrons are antisocial: no two can occupy the same quantum state. Fermi worked out what this rule implies for a gas of many particles. Even at absolute zero, the electrons in a metal must fill a ladder of states up to a high energy, now called the Fermi energy. That single fact explains why metals conduct, why white dwarf stars do not collapse, and why atoms have the sizes they do.

History

Fermi had been worried since 1924 that classical ideal-gas theory gives the wrong entropy at low temperature, and that a correct theory needed to quantize the motion of the gas particles. When Pauli’s exclusion principle appeared in 1925, Fermi applied it to an ideal gas in a note presented to the Accademia dei Lincei early in 1926, Sulla quantizzazione del gas perfetto monoatomico, followed by a longer German version in Zeitschrift für Physik. Later in 1926 Paul Dirac reached the same statistics from the antisymmetry of the many-particle wavefunction, and credited Fermi. Dirac later coined the word fermion. Pascual Jordan had found the statistics in 1925 but did not publish in time. Within two years Ralph Fowler applied it to white dwarfs (1926) and Arnold Sommerfeld to electrons in metals (1927).

Derivation

Consider non-interacting identical particles with single-particle levels \(\varepsilon_i\). In the grand canonical ensemble at temperature \(T\) and chemical potential \(\mu\), the levels are independent, and the exclusion principle allows each occupation number \(n_i\) to be 0 or 1 only. The grand partition function of one level is \(\mathcal Z_i=1+e^{-\beta(\varepsilon_i-\mu)}\) with \(\beta=1/k_BT\), so

The degenerate gas

For free particles of mass \(m\) and spin \(\tfrac12\) in volume \(V\), there are \(2\cdot V\,d^3p/(2\pi\hbar)^3\) states in \(d^3p\). At \(T=0\) the occupied states fill a sphere of radius \(p_F\) in momentum space, so \(N=2V\cdot\frac{4\pi p_F^3}{3(2\pi\hbar)^3}\), giving

The pressure \(P=\tfrac23 E/V\) does not vanish at zero temperature: this is degeneracy pressure. For copper, \(n\approx8.5\times10^{28}\,\mathrm m^{-3}\) gives \(E_F\approx7\) eV, so the Fermi temperature \(E_F/k_B\) is about \(8\times10^4\) K and room temperature is very cold for the electrons.

The Sommerfeld expansion

For \(k_BT\ll E_F\), only states within about \(k_BT\) of \(E_F\) can change their occupation. With density of states \(g(\varepsilon)\), integrals expand as

This gives an electronic heat capacity \(C_V=\frac{\pi^2}{2}Nk_B\frac{k_BT}{E_F}\), linear in \(T\) and far smaller than the classical \(\tfrac32Nk_B\). That resolved a puzzle of the Drude model of metals.

The theory of beta decay

For the general reader. Some nuclei change one neutron into a proton and shoot out an electron. The electrons come out with a spread of energies, which seemed to break energy conservation. Pauli proposed that an unseen neutral particle carries off the missing energy. Fermi named it the neutrino and wrote the first theory of how the decay happens. The theory introduced a new force of nature, now called the weak interaction.

The problem

By 1930 it was known that beta electrons have a continuous energy spectrum up to an end point. In a letter of December 1930 Pauli suggested a light neutral spin-½ particle emitted with the electron. After James Chadwick discovered the neutron in 1932, Fermi saw how to build a theory. Electrons and neutrinos do not exist inside nuclei; they are created at the moment of decay, just as photons are created when an atom radiates. He used the methods of quantum electrodynamics, with the electron–neutrino pair playing the role of the photon.

A short version appeared in La Ricerca Scientifica in December 1933, after Nature declined the letter as too remote from physical reality. The full theory appeared in Il Nuovo Cimento and in Zeitschrift für Physik 88 in 1934.

The normalization factor \(1/\sqrt2\) is today’s convention; Fermi’s original \(g\) differs by such factors. What matters is that \(G\) has dimensions of energy times volume, and that it is small: the weak interaction is short-ranged and feeble at low energy.

The spectrum

The decay rate follows from time-dependent perturbation theory. Fermi’s calculation uses the formula that his 1950 Chicago lecture notes call Golden Rule No. 2:

For an allowed transition the matrix element is nearly independent of the lepton momenta, so the spectrum is set by phase space. With electron momentum \(p\) and total energy \(E\), massless neutrino of momentum \(q=(E_0-E)/c\), and end-point total energy \(E_0\) (the nuclear recoil carries momentum but negligible energy):

Here \(F(Z,E)\) is the Fermi function, which corrects for the Coulomb attraction or repulsion of the daughter nucleus on the electron (or positron). Fermi computed it in the 1934 paper and compared the shapes with data, concluding that the neutrino mass is zero or very small compared with the electron mass.

Neutron-induced radioactivity and slow neutrons

For the general reader. In 1934 Fermi’s group fired neutrons at every element they could obtain and made dozens of new radioactive isotopes. Then they found something unexpected: neutrons slowed down by passing through paraffin or water are far more effective than fast ones. That discovery made nuclear reactors possible.

Neutron activation

In January 1934 Irène Joliot-Curie and Frédéric Joliot produced artificial radioactivity with alpha particles. Alpha particles are repelled by heavy nuclei. Fermi reasoned that neutrons, which feel no Coulomb barrier, should work on every element, even though the available neutron sources were weak. He used sealed tubes of radon gas mixed with beryllium powder: the alpha particles from radon knock neutrons out of beryllium. On 25 March 1934 he reported induced radioactivity in La Ricerca Scientifica, and the group then worked through the periodic table in order. By the summer they had activated more than 20 elements.

Bombarding uranium produced activities that they tentatively attributed to transuranic elements. Ida Noddack suggested that the nucleus might instead have broken into large fragments, but the idea was not taken up. In December 1938 Otto Hahn and Fritz Strassmann found barium among the products, and Lise Meitner and Otto Frisch identified the process as fission.

22 October 1934

Amaldi and Pontecorvo noticed that the activity induced in silver depended on where the sample stood: on a wooden bench it was stronger than on marble. On the morning of 22 October 1934 Fermi planned to place a lead filter between source and target, then on impulse used paraffin wax instead. The activity rose by a factor of about 100. By the afternoon Fermi had the explanation: neutrons lose energy in collisions with the hydrogen nuclei in paraffin, and slow neutrons are captured far more readily. The group checked the effect with the water of the fountain in the institute garden, and published with Rasetti and Segrè in Ricerca Scientifica. The Nobel Prize of 1938 cited both the new radioactive elements produced by neutron irradiation and the nuclear reactions brought about by slow neutrons.

Slowing down by elastic collisions

A neutron of energy \(E\) scattering elastically and isotropically (in the centre-of-mass frame) off a nucleus of mass number \(A\) emerges with energy uniformly distributed in \([\alpha E,E]\), where

Fermi went further and treated the slowing down of neutrons in a large moderator as diffusion in the variable \(\tau\), the Fermi age, which plays the role of time: the slowing-down density obeys \(\partial q/\partial\tau=\nabla^2q\).

Why slow neutrons are captured

For capture far from any resonance, the reaction rate is set by the time the neutron spends near the nucleus, so the cross section scales as \(\sigma\propto1/v\). The capture rate per target nucleus is \(n\,v\,\sigma(v)\), which is then independent of speed. Near low-energy resonances, which Fermi’s group also found in 1935–36, capture can be much stronger still.

CP-1 and criticality

For the general reader. When a uranium nucleus splits, it releases two or three neutrons. If on average exactly one of them causes another fission, the reaction sustains itself. On 2 December 1942, under the stands of a football field in Chicago, Fermi’s team showed that a pile of graphite and uranium could reach that balance and be controlled.

The multiplication factor

Let \(k\) be the mean number of fissions in one generation caused by the neutrons from one fission in the previous generation. For an infinite medium of natural uranium and moderator, the standard decomposition of the 1940s is

where \(\eta\) is the number of fast neutrons produced per thermal neutron absorbed in uranium, \(\varepsilon\) the fast-fission bonus from uranium-238, \(p\) the probability of escaping resonance capture while slowing down, and \(f\) the fraction of thermal neutrons absorbed in uranium rather than in the moderator. For natural uranium \(\eta\approx1.33\), so the product of the other three must exceed about 0.75. Fermi and Leo Szilard realized that lumping the uranium in a lattice raises \(p\): a neutron slowing down in graphite between lumps rarely meets uranium-238 at its resonance energies.

Critical size

A finite pile leaks neutrons. In one-group diffusion theory with migration area \(M^2\), the neutron flux in a bare homogeneous pile satisfies \(\nabla^2\phi+B^2\phi=0\), vanishing at the (extrapolated) boundary.

At Columbia and then Chicago in 1941–42 Fermi built a series of subcritical exponential piles and measured \(k_\infty\) for different lattices. The first Columbia pile gave about 0.87; purer graphite and uranium oxide, and then uranium metal, pushed the value above 1. The Chicago pile was designed as a sphere. Fermi’s team measured the neutron intensity layer by layer and extrapolated the layer at which the pile would go critical, which allowed them to stop short of the full sphere. Work stopped at layer 57, giving a flattened ellipsoid about 7.6 m across and 6 m high, built from about 45,000 graphite blocks with uranium oxide and uranium metal in a lattice.

Kinetics and delayed neutrons

If \(\ell\) is the mean neutron lifetime from birth to absorption, the population \(n\) obeys

About 0.65 percent of the neutrons from uranium-235 fission (\(\beta\approx0.0065\)) are emitted by fission products after delays of seconds to about a minute, mean about 13 s. As long as \(k-1<\beta\), the chain depends on them, and the effective lifetime is \(\ell_{\mathrm{eff}}\approx\ell+\beta\bar\tau\), about a tenth of a second, instead of about a millisecond for prompt neutrons in graphite. That makes the period minutes long, and control rods have time to act.

On 2 December 1942, with 49 people present, George Weil withdrew the last cadmium control rod step by step on Fermi’s instructions. At 3:25 p.m. the counters showed an exponential rise that did not level off. Fermi let it run for several minutes at about half a watt, then ordered the rods back in. Arthur Compton telephoned James Conant in code: the Italian navigator had landed in the New World.

Fermi estimation

For the general reader. Fermi could get a useful answer to almost any quantitative question in a few minutes, with no data beyond what he carried in his head. The trick is to break the question into factors you can guess within a factor of two or three, and multiply. Physicists now call these Fermi problems.

The method

The classic example asks how many piano tuners work in Chicago. Population, people per household, the fraction of households with a piano, tunings per piano per year, and tunings one tuner can do in a year are each guessable. Multiplying them gives an answer, and comparing it with reality shows which factor was wrong. Fermi taught this style to his students in Chicago, and it became part of physics culture.

Trinity

On 16 July 1945, at the Trinity test, Fermi stood about 16 km from the bomb. When the blast wave arrived some 40 seconds after the flash, he dropped small pieces of paper from about shoulder height and saw them carried about 2.5 m. From this displacement he estimated a yield of about 10 kilotons of TNT. Modern assessments put the yield at about 20 to 25 kilotons, so he was within a factor of about two. His note gives the result but not the full calculation.

A related estimate comes from dimensional analysis. If a point explosion releases energy \(E\) in air of density \(\rho\), the fireball radius \(R\) at time \(t\) can depend only on \(E,\rho,t\). The only combination with dimensions of length is

G. I. Taylor used this law, with photographs of the Trinity fireball released in 1947, to estimate the yield.

Pions and the first resonance

For the general reader. After the war Fermi moved from nuclear physics to the new physics of particles. With the Chicago synchrocyclotron he scattered pions off protons and found that the scattering rises steeply with energy, following a rule fixed by a hidden symmetry called isospin. This was the first glimpse of an excited state of the proton, the Delta, and the start of hadron spectroscopy.

Background

Hideki Yukawa had predicted in 1935 a meson carrying the nuclear force, and the charged pion was found in cosmic rays in 1947. In 1949 Fermi and Chen Ning Yang asked whether the pion might be a bound state of a nucleon and an antinucleon, an idea later revived in the quark model. In 1950 Fermi proposed a statistical theory of multiple pion production in high-energy collisions. In 1952 his group, with Herbert Anderson, E. A. Long, D. E. Nagle and others, published in Physical Review the total cross sections of positive and negative pions in hydrogen, and the ordinary and charge-exchange scattering of negative pions.

Isospin

The nucleon is an isospin doublet (\(p=|\tfrac12,\tfrac12\rangle\), \(n=|\tfrac12,-\tfrac12\rangle\)) and the pion a triplet. If the strong interaction conserves isospin, the scattering amplitude depends only on the total isospin \(I\in\{\tfrac12,\tfrac32\}\). Clebsch–Gordan coefficients give

The Chicago data, up to pion kinetic energies of about 135 MeV, showed the \(\pi^+p\) cross section rising steeply and roughly three times the \(\pi^-p\) cross section, with charge exchange about twice elastic \(\pi^-p\) scattering. Keith Brueckner interpreted the rise as a resonance in the state with \(I=\tfrac32\), \(J=\tfrac32\). Later measurements found the peak at a pion kinetic energy near 190 MeV. It is now the \(\Delta(1232)\).

The Fermi–Pasta–Ulam–Tsingou problem

For the general reader. Fermi wanted to watch a physical system reach thermal equilibrium on one of the first electronic computers. He chose a chain of masses joined by slightly nonlinear springs, put all the energy in the slowest vibration, and expected it to spread evenly over all vibrations. It did not. After a while the energy came back almost entirely to where it started. This surprise launched the computer experiment as a method, and later led to the discovery of solitons.

The experiment

In the summer of 1953 at Los Alamos, Fermi, John Pasta and Stanislaw Ulam ran the calculation on the MANIAC computer. Mary Tsingou wrote the program and carried out the runs; her role was acknowledged in the report but long overlooked, and Thierry Dauxois proposed in 2008 that her name be added. The results appeared in May 1955, after Fermi’s death, as Los Alamos report LA-1940, Studies of Nonlinear Problems.

The quadratic term couples the modes. Statistical mechanics predicts that the energy should spread until, on average, each mode holds the same share. In the runs with \(N=32\) and energy started in mode 1, energy flowed into modes 2, 3, 4 and then flowed back. A rerun of the standard case (\(N=32\), \(\alpha=\tfrac14\), initial amplitude 1) brings about 97 percent of the energy back to mode 1 after roughly 150 periods of that mode. Later work showed that equipartition does occur, but on time scales far longer than those of the original runs.

Solitons

In 1965 Norman Zabusky and Martin Kruskal took the continuum limit of the chain. Keeping the leading dispersive and nonlinear terms, a long wave moving in one direction obeys the Korteweg–de Vries equation \(u_t+uu_x+\delta^2u_{xxx}=0\). In numerical solutions they saw localized pulses that passed through each other unchanged, and named them solitons. Their exact solvability, through the inverse scattering transform (1967), opened the theory of integrable systems. Kolmogorov–Arnold–Moser theory, developed in the same years, explains why weakly perturbed integrable systems can keep quasi-periodic motion for a long time.

Exile, war and the Manhattan Project, 1938–1945

In 1938 Fascist Italy adopted racial laws modelled on those of Nazi Germany. Laura Fermi was Jewish, and so were several of Fermi’s collaborators. In November 1938 he learned that he had been awarded the Nobel Prize in Physics. On 6 December the family left Rome for Stockholm, where he received the prize on 10 December and lectured on artificial radioactivity produced by neutron bombardment. They sailed on to New York, arriving on 2 January 1939, and Fermi took up a professorship at Columbia University.

Within weeks Niels Bohr brought news of fission to America. On 25 January 1939 a Columbia group including Fermi observed fission in the basement of Pupin Hall. Fermi, Szilard and others measured that fission releases more than one neutron, and the possibility of a chain reaction became real. After the Einstein–Szilard letter to President Roosevelt, the government began to fund the work. In 1942 the project moved to Arthur Compton’s Metallurgical Laboratory in Chicago, where Fermi led the construction of CP-1 (Lesson 07). The Fermis became American citizens on 11 July 1944.

Fermi then helped start the X-10 reactor at Oak Ridge and, in September 1944, the B reactor at Hanford, which built up plutonium for the bombs. When the Hanford reactor unexpectedly shut itself down, Fermi and John Wheeler traced the cause to xenon-135, a fission product that absorbs neutrons strongly. In the autumn of 1944 he moved to Los Alamos at J. Robert Oppenheimer’s request, as an associate director in charge of F Division, a group for problems that fitted nowhere else, including early work on the thermonuclear bomb. He was a member of the scientific panel that advised on the use of the bomb in 1945, and he watched the Trinity test on 16 July (Lesson 08).

Chicago, death and legacy, 1945–1954

On 1 July 1945 Fermi became Charles H. Swift Distinguished Professor of Physics at the University of Chicago, and he helped found its Institute for Nuclear Studies. His seminars and courses produced an extraordinary group of students and postdocs. His doctoral students in Rome and Chicago included Edoardo Amaldi, Emilio Segrè, Ettore Majorana, Owen Chamberlain, Geoffrey Chew, Jerome Friedman, Richard Garwin, Marvin Goldberger, Tsung-Dao Lee, Arthur Rosenfeld, Sam Treiman, Harold Agnew and Mildred Dresselhaus; Chen Ning Yang and Jack Steinberger also worked closely with him. Segrè, Chamberlain, Lee, Yang, Friedman and Steinberger later won Nobel Prizes.

His research turned to particles (Lesson 09), to computation (Lesson 10), and to astrophysics. In 1949 he proposed that cosmic rays gain energy by bouncing off moving magnetized clouds in the galaxy. This mechanism, Fermi acceleration, in its later shock-wave form, remains the standard explanation of cosmic-ray spectra. During a lunch at Los Alamos in 1950 he asked where everybody was, if intelligent life is common in the galaxy: the question now called the Fermi paradox.

From 1947 to 1950 Fermi served on the General Advisory Committee of the Atomic Energy Commission, chaired by Oppenheimer. In 1949, after the first Soviet bomb, he and Isidor Rabi wrote an annex to the committee’s report opposing a crash programme for the hydrogen bomb on ethical grounds, although he later consulted on the work. In 1954 he testified at the security hearing of Oppenheimer in support of his former colleague.

In the summer of 1954 he lectured in Varenna and near Chamonix. An exploratory operation in October 1954 found inoperable stomach cancer. He died at his home in Chicago on 28 November 1954, aged 53, and is buried in Oak Woods Cemetery.

Legacy

• Physics: Fermi–Dirac statistics, the theory of the weak interaction, slow-neutron physics, the nuclear reactor, the first hadron resonance, cosmic-ray acceleration, and the computer experiment.
• Honours in life: Matteucci Medal (1926), Nobel Prize in Physics (1938), Hughes Medal (1942), Medal for Merit (1946), Franklin Medal (1947), Foreign Member of the Royal Society (1950), Rumford Prize (1953), Max Planck Medal (1954).
• Names: element 100, fermium, identified in the debris of the 1952 Ivy Mike test; the Enrico Fermi Award of the Atomic Energy Commission and its successors; Fermilab, so named in 1974; the Fermi Gamma-ray Space Telescope (2008).
• Teaching: his lecture notes on nuclear physics, quantum mechanics and thermodynamics are still read, and his estimation style shapes how physicists are trained.

Connections

People linked to Enrico Fermi across this collection. A name without a link has no page here yet. See Enrico Fermi in the network of all 337 lives →

Teachers and advisors

• Luigi Puccianti 1922

Students

• Arthur Rosenfeld
• Chen Ning Yang
• Edoardo Amaldi
• Emilio Segrè
• Ettore Majorana
• Geoffrey Chew
• Harold Agnew
• Jack Steinberger
• Jerome Isaac Friedman
• Marvin Goldberger
• Mildred Dresselhaus
• Owen Chamberlain
• Richard Garwin
• Sam Treiman
• Tsung-Dao Lee

Influenced by

• Frédéric Joliot-Curie
• Irène Joliot-Curie
• James Chadwick
• Paul Ehrenfest 1924
• Wolfgang Pauli

Influenced

• George Gamow
• Hans Bethe 1931-1932
• Irène Joliot-Curie
• Lise Meitner 1934
• Otto Hahn 1934

Colleagues and collaborators

• Arthur Compton 1942-1945
• Hans Bethe
• J. Robert Oppenheimer 1944-1954
• Lise Meitner
• Max Born 1923
• Niels Bohr
• Otto Hahn
• Paul Dirac
• Stanislaw Ulam 1953
• Tullio Levi-Civita
• Bruno Pontecorvo 1934-1936
• Franco Rasetti 1919-1938
• Herbert L. Anderson 1939-1954
• Isidor Isaac Rabi
• John Archibald Wheeler
• John Pasta 1953
• Leo Szilard 1939-1942
• Llewellyn Thomas
• Mary Tsingou 1953
• Orso Mario Corbino 1926-1937
• Walter Zinn 1939-1945

Rivals

• Frédéric Joliot-Curie

Friends

• Enrico Persico

Also mentioned in this life

• Ludwig Boltzmann
• Subrahmanyan Chandrasekhar
• Charles-Augustin de Coulomb
• Albert Einstein
• Joseph Fourier
• Benjamin Franklin
• G. I. Taylor
• Paul Gordan
• Werner Heisenberg
• Andrey Kolmogorov
• James Clerk Maxwell
• Max Planck
• Count Rumford
• Arnold Sommerfeld

Fields

• nuclear physics 13 lives
• statistical mechanics 8 lives
• quantum theory 6 lives

On CoursesHub

• Nuclear Physics
• Particle Physics
• Statistical Mechanics

Sources and further reading

Biography

1. Enrico Fermi, Wikipedia (with extensive references).
2. J. J. O’Connor and E. F. Robertson, Enrico Fermi, MacTutor History of Mathematics.
3. The Nobel Prize, Enrico Fermi: facts, Nobel Prize in Physics 1938.
4. Via Panisperna boys, Wikipedia.
5. L. Fermi, Atoms in the Family: My Life with Enrico Fermi, University of Chicago Press, 1954.
6. E. Segrè, Enrico Fermi, Physicist, University of Chicago Press, 1970.
7. D. N. Schwartz, The Last Man Who Knew Everything: The Life and Times of Enrico Fermi, Basic Books, 2017.
8. G. Segrè and B. Hoerlin, The Pope of Physics, Henry Holt, 2016.

Physics

1. E. Fermi, Sulla quantizzazione del gas perfetto monoatomico, Rend. Lincei 3 (1926) 145–149; English translation by A. Zannoni.
2. E. Fermi, Versuch einer Theorie der β-Strahlen, Z. Phys. 88 (1934) 161; English translation by F. L. Wilson, Am. J. Phys. 36 (1968) 1150.
3. E. Fermi, E. Amaldi, B. Pontecorvo, F. Rasetti, E. Segrè, Azione di sostanze idrogenate sulla radioattività provocata da neutroni, Ric. Scient. 5 (1934) 282.
4. G. Bernardini et al., Chance and necessity in Fermi’s discovery of the properties of the slow neutrons, arXiv:physics/0201028.
5. E. Fermi, Artificial radioactivity produced by neutron bombardment, Nobel Lecture, 12 December 1938.
6. Chicago Pile-1, Wikipedia; F. Guerra, N. Robotti, Enrico Fermi and the physics and engineering of a nuclear pile, arXiv:0803.1145.
7. E. Fermi, My observations during the explosion at Trinity on July 16, 1945.
8. E. Fermi, On the origin of the cosmic radiation, Phys. Rev. 75 (1949) 1169.
9. E. Fermi, C. N. Yang, Are mesons elementary particles?, Phys. Rev. 76 (1949) 1739.
10. H. L. Anderson, E. Fermi, E. A. Long, D. E. Nagle, Total cross sections of positive pions in hydrogen, Phys. Rev. 85 (1952) 936; and companion papers on pp. 934–935.
11. E. Fermi, J. Pasta, S. Ulam, Studies of nonlinear problems, Los Alamos report LA-1940 (1955); overview.
12. T. Dauxois, Fermi, Pasta, Ulam and a mysterious lady, arXiv:0801.1590, Physics Today 61 (2008).
13. N. J. Zabusky, M. D. Kruskal, Interaction of solitons in a collisionless plasma and the recurrence of initial states, Phys. Rev. Lett. 15 (1965) 240.
14. E. Fermi, Nuclear Physics, lecture notes compiled by J. Orear, A. H. Rosenfeld, R. A. Schluter, University of Chicago Press, 1950.