← Part V: The Atomic Revolution

Göttingen: The Capital of Physics

How a small German university town became the epicentre of the quantum revolution, producing more Nobel laureates per square metre than anywhere else in history.

1895Klein &Hilbert arrive1904Minkowskispacetime1915HilbertGR action1921Bornappointed1925Heisenbergmatrix QM1926Born ruleprobability1927Uncertaintyprinciple1933Nazi purgeexodusGöttingen physics timeline (1895–1933)

The Early Seeds: Isolated Quantum Contributions (1903–1918)

Göttingen's path to becoming the birthplace of quantum mechanics was not a straight line. The relevant publications before the 1920s revolution emerged as isolated and mostly unrecognised works that do not combine easily into a satisfactory narrative. Yet they laid essential groundwork.

The Scattered Pioneers

Walter Ritz (1903, 1908)

Formulated the combination principle for spectral lines — a key empirical rule that any complete quantum theory would need to explain. His work was ahead of its time and largely unrecognised.

Max Abraham (1904)

Contributed early theoretical work on black-body radiation from Göttingen, engaging with Planck’s quantum hypothesis before most physicists took it seriously.

Paul Ehrenfest

Spent considerable time in Göttingen and was instrumental in recognising the inevitable discontinuity entailed by the quantum hypothesis. However, he was unable to gain a position or influence at the university.

Walther Nernst

Developed his heat theorem (the Third Law of Thermodynamics) while at Göttingen, though he was already preparing to leave for Berlin when the work reached fruition.

Johannes Stark

Made his discovery of the Stark effect (splitting of spectral lines by electric fields) only after leaving Göttingen, having taken with him the general idea from Woldemar Voigt.

Woldemar Voigt

Professor of theoretical physics who influenced both Stark and later researchers, though his own contributions to quantum theory remained indirect.

Max Born's Early Path to the Quantum

Max Born turned to Thomson's atom for his habilitation lecture and attended Albert Einstein's landmark Salzburg talk in 1909, developing an early interest in atomic physics and the quantum question. His pre-war contributions included:

  • ‱ Work with Rudolf Ladenburg on black-body radiation
  • ‱ Papers with Theodore von KĂĄrmĂĄn on specific heat (simultaneously with Peter Debye)
  • ‱ Work with Richard Courant relating quantum theory to the law of Eötvös and surface tension of liquids

The War Years and Bohr's Atom

During World War I, both Born and Peter Debye focused on the question of what results would come from Bohr's atom if taken seriously. Born, together with Alfred Landé and Erwin Madelung, formed a kind of Berlin outpost of Göttingen physicists in military service, using Bohr's quantum theory for the constitution of matter. Debye and Paul Scherrer applied it to the diffraction of X-rays. Debye also brought in the quantum for the Zeeman effect (in parallel with Arnold Sommerfeld).

“At this time the quantum, as the key to the atomic structure of matter, became the Göttingen credo. After the war — when the failures of the Bohr atom became apparent — it was the quantum that opened up the fruitful road to matrix mechanics as paved by Born and James Franck.”

The Hidden Architect: David Hilbert

Remarkably, one person central to the Göttingen story — the mathematician David Hilbert — published nothing directly on quantum or atomic problems, and citations of his influence are few. Yet his creation of the mathematical infrastructure (Hilbert spaces, integral equations, spectral theory) and the intellectual culture he fostered at Göttingen were indispensable conditions for the quantum revolution. The purely conceptual history of quantum mechanics, focused on journal publications, misses the wider local context — the seminars, corridors, and coffee houses — in which knowledge was actually created.

The Mathematical Foundation (1895–1915)

Göttingen's rise began with mathematics, not physics. Carl Friedrich Gauss had established its mathematical reputation in the early 19th century, but the transformation into a physics powerhouse started when Felix Klein recruited David Hilbert in 1895.

Hilbert's Programme

Hilbert turned Göttingen into the world capital of mathematics. His 1900 address at the International Congress of Mathematicians listed 23 unsolved problems that shaped 20th-century research. His work on integral equations (1904–1910) created the mathematical framework — Hilbert spaces — that would become the language of quantum mechanics two decades later.

Minkowski's Spacetime (1907)

Hermann Minkowski, Hilbert's colleague and Einstein's former teacher in ZĂŒrich, reformulated special relativity as geometry of a 4-dimensional spacetime manifold:

$$ds^2 = -c^2 dt^2 + dx^2 + dy^2 + dz^2$$

His famous declaration: “Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality.”This geometric viewpoint was essential for Einstein's development of general relativity.

Hilbert and General Relativity (1915)

In November 1915, Hilbert derived the gravitational field equations from a variational principle — the Einstein–Hilbert action — arriving at the same equations as Einstein within days:

$$S = \frac{1}{16\pi G}\int \sqrt{-g}\, R\, d^4x$$

The priority dispute between Einstein and Hilbert remains one of the most famous in physics history. What is certain: Göttingen's mathematical culture made it the only place outside Berlin where general relativity could be independently derived.

The Quantum Revolution (1921–1927)

Max Born's Institute

In 1921, Max Born was appointed director of the Institute for Theoretical Physics. He assembled the most extraordinary group of young physicists ever gathered in one place: Werner Heisenberg, Wolfgang Pauli, Pascual Jordan, Enrico Fermi, J. Robert Oppenheimer, Maria Goeppert-Mayer, Edward Teller, and Eugene Wigner, among many others.

Matrix Mechanics (June 1925)

Werner Heisenberg, Born's 23-year-old assistant, retreated to the island of Helgoland to escape hay fever. There he had the breakthrough: observable quantities should be represented by matrices (arrays of transition amplitudes), not classical orbits. Back in Göttingen, Born recognised Heisenberg's multiplication rule as matrix multiplication:

$$pq - qp = \frac{\hbar}{i}\mathbf{1}$$

The Born–Heisenberg–Jordan “DreimĂ€nnerarbeit” (three-man paper, November 1925) established the complete mathematical framework of matrix mechanics — the first rigorous formulation of quantum mechanics.

The Born Rule (1926)

When Schrödinger published wave mechanics from ZĂŒrich, Born provided its physical interpretation: the wave function $\psi$ gives the probability amplitude, and $|\psi|^2$ gives the probability density. This was the most radical break with classical determinism:

$$P(x) = |\psi(x)|^2$$

Born received the Nobel Prize for this in 1954 — 28 years after the discovery, one of the longest waits in Nobel history. Einstein never accepted the probabilistic interpretation, leading to the famous Bohr–Einstein debates.

The Uncertainty Principle (1927)

Heisenberg, still at Göttingen, derived the fundamental limit on simultaneous measurements:

$$\Delta x \cdot \Delta p \geq \frac{\hbar}{2}$$

The Göttingen School: People & Legacy

David Hilbert

1895–1930 — Mathematics chair

Hilbert spaces, GR variational principle, 23 problems

Max Born

Nobel 1954

1921–1933 — Director of Theoretical Physics

Matrix mechanics, Born rule, Born approximation

Werner Heisenberg

Nobel 1932

1922–1927 — Born’s assistant

Matrix mechanics, uncertainty principle

Wolfgang Pauli

Nobel 1945

1921–1922 — Born’s assistant

Exclusion principle, spin-statistics

J. Robert Oppenheimer

1926–1927 — PhD student (Born)

Born–Oppenheimer approximation, later Manhattan Project

Maria Goeppert-Mayer

Nobel 1963

1924–1930 — PhD student (Born)

Nuclear shell model, two-photon absorption

Enrico Fermi

Nobel 1938

1923 — Visiting scholar

Fermi statistics, beta decay theory, nuclear reactor

Eugene Wigner

Nobel 1963

1927–1928 — Hilbert’s assistant

Group theory in QM, symmetry principles

John von Neumann

1926–1929 — Privatdozent

Mathematical foundations of QM, operator algebras

Edward Teller

1930–1933 — PhD student

Jahn–Teller effect, hydrogen bomb

Pascual Jordan

1923–1929 — Born’s student

Matrix mechanics co-author, quantum field theory

Emmy Noether

1915–1933 — Mathematician

Noether’s theorem (symmetry ↔ conservation)

Nobel Prize Count

At least 14 Nobel laureates studied, worked, or received their PhD at Göttingen during the quantum revolution years (1920s–1930s). No other institution in history has produced such a concentration of transformative physics in such a short period.

Emmy Noether: The Theorem That Changed Physics

Emmy Noether arrived in Göttingen in 1915 at the invitation of Hilbert and Klein. Despite facing extreme discrimination as a woman in academia (she could not officially hold a position and had to lecture under Hilbert's name), she proved what is arguably the most profound theorem connecting mathematics and physics:

Noether's Theorem (1918)

Every continuous symmetry of the action of a physical system corresponds to a conserved quantity.

$$\frac{\partial \mathcal{L}}{\partial q}\delta q + \frac{\partial \mathcal{L}}{\partial \dot{q}}\delta\dot{q} = \frac{d}{dt}\left(\frac{\partial \mathcal{L}}{\partial \dot{q}}\delta q\right)$$

Time symmetry
↔ Energy conservation
Space symmetry
↔ Momentum conservation
Rotation symmetry
↔ Angular momentum

Noether's theorem is the foundation of modern gauge theory, the Standard Model, and the BMS asymptotic symmetries studied in the Unification course — all flowing from work done in Göttingen.

Research Politics: The Personnel Revolution (1900–1926)

Scientific change is most often also a change of scientists — and at Göttingen, many of these changes were made intentionally. The deliberate recruitment strategy of Felix Klein and David Hilbert, combined with the flexibility of the Prussian ministerial system, transformed Göttingen from a mathematics department into the world's leading centre for mathematical physics. Understanding who was hired, why, and who was passed over reveals the institutional forces behind the quantum revolution.

Klein's Strategic Vision

Felix Klein (1849–1925) was not just a mathematician but an institution-builder. He understood that modern physics required a new kind of scientist — one fluent in both rigorous mathematics and physical intuition. His key moves:

  • ‱ Recruited Hilbert (1895) from Königsberg — securing the greatest mathematician of the era
  • ‱ Recruited Hermann Minkowski (1902) — who would reformulate special relativity as geometry
  • ‱ Created the Mathematical Physics Seminar — institutionalising the collaboration between mathematicians and physicists
  • ‱ Established ties with the Prussian Ministry of Education to fund new positions and institutes
  • ‱ Fought to bring Emmy Noether to Göttingen (1915) despite fierce opposition to women in academia

The Chair Appointments That Built the Revolution

German ministerial and university bureaucracy kept detailed records of the complex processes for filling professorial positions. These records reveal a pattern of deliberate structural change in Göttingen's physics and mathematics departments:

1900

Woldemar Voigt holds theoretical physics

Traditional approach; influenced Stark but did not embrace the quantum

1904–1914

Debye, Runge, Abraham in applied mathematics/physics

Created a culture of computational and experimental rigour

1914

Peter Debye appointed to theoretical physics

Brought modern statistical mechanics and quantum theory of solids

1920

James Franck appointed to experimental physics

Key hire: Franck’s precision experiments (Franck–Hertz) provided the data quantum theory needed

1921

Max Born appointed director of theoretical physics

The decisive appointment: Born created the intellectual environment for the quantum revolution

1922

Born hires Heisenberg as his assistant

A 20-year-old from Sommerfeld’s Munich school — the most consequential hiring decision in physics history

1925–1926

Pauli, Jordan, Oppenheimer arrive

Born’s institute becomes a magnet for the most talented young physicists worldwide

The Born–Franck Partnership

The simultaneous appointment of Max Born (theory) and James Franck (experiment) in 1920–1921 was perhaps the most important institutional decision in the history of quantum physics. Born provided the mathematical framework; Franck provided the experimental data. Their institutes were physically adjacent, and they maintained a daily working relationship that ensured theory and experiment evolved together. This was not accidental — it was deliberately engineered by the faculty and ministry.

The Role of the Seminars

Göttingen's famous seminars were not mere lecture series but working sessions where problems were posed, debated, and often solved in real time. The Hilbert–Klein seminar on mathematical physics, the Born colloquium, and the Franck experimental seminar created an environment where a young researcher like Heisenberg could present a half-formed idea on Monday and have it turned into a rigorous theory by Friday — with contributions from mathematicians, experimentalists, and fellow theorists all in the same room.

The purely conceptual history of quantum mechanics, focused on idealised discussions in journals, misses the wider local context — the seminars, corridors, and coffee houses — in which knowledge was actually created. The Göttingen story shows that the conditions for revolutionary science are as much institutional as intellectual.

The Destruction (1933)

On April 7, 1933, the Nazi “Law for the Restoration of the Professional Civil Service” dismissed all Jewish and politically “unreliable” academics. Göttingen was devastated:

  • ‱ Max Born — dismissed, fled to Edinburgh
  • ‱ Emmy Noether — dismissed, emigrated to Bryn Mawr (died 1935)
  • ‱ James Franck — resigned in protest, emigrated to USA
  • ‱ Richard Courant — dismissed, founded the Courant Institute at NYU
  • ‱ Edward Teller, Eugene Wigner, John von Neumann — already departed or forced out

When the Nazi education minister asked Hilbert at a banquet: “How is mathematics in Göttingen, now that it has been freed of the Jewish influence?” Hilbert replied:

“Mathematics in Göttingen? There is really none anymore.”

The exodus from Göttingen transformed American physics: Born's students and colleagues went on to build the Manhattan Project, establish quantum mechanics curricula across US universities, and create the modern research institutions that dominate physics today. Göttingen never recovered its pre-1933 status.

Legacy: What Göttingen Gave the World

Matrix Mechanics

The first complete formulation of quantum mechanics (Heisenberg, Born, Jordan, 1925)

The Born Rule

Probability interpretation of quantum mechanics (Born, 1926)

Uncertainty Principle

Fundamental limit on measurement precision (Heisenberg, 1927)

Noether’s Theorem

Symmetry ↔ conservation law correspondence (Noether, 1918)

Hilbert Spaces

Mathematical foundation of quantum mechanics (Hilbert, von Neumann)

Einstein–Hilbert Action

Variational principle for general relativity (Hilbert, 1915)

Born–Oppenheimer Approximation

Separation of nuclear and electronic motion in molecules (1927)

Franck–Hertz Experiment

First direct proof of quantised energy levels (Franck & Hertz, 1914)

Paul Dirac — Interview in Göttingen (1982)

A rare interview with Paul Dirac, recorded in Göttingen in 1982 — one of the founders of quantum mechanics reflecting on the revolutionary period at the university where so much of modern physics was born.

Rate this chapter: