Arnold Sommerfeld

! scientist · # tag · @ author

1868–1951 · Quantum mechanics, Atomic physics, Solid state physics

German theoretical physicist, teacher and mentor of a whole generation of creators of quantum mechanics. Introduced fine structure and the principal quantum number into the Bohr atom model, developed the theory of metals and relativistic quantum effects. The fine-structure constant—a dimensionless constant that determines the strength of electromagnetic interaction—is named after him.

Biography

Studied at the University of Königsberg, worked at the universities of Göttingen, Munich, and others. His students included Heisenberg, Pauli, Debye, Bethe. Never received the Nobel Prize, although he was nominated more than 80 times. Author of the epochal course 'Lectures on Theoretical Physics'.

Key discoveries

Bohr–Sommerfeld atom model: extended Bohr's theory by introducing elliptical orbits and relativistic corrections, which explained the fine structure of spectra (1916).
Fine-structure constant: first interpreted α ≈ 1/137 as a fundamental constant characterizing electromagnetic interaction.
Theory of metals: created the quantum theory of free electrons in metals, explaining their conductivity.

💡 Sommerfeld is often called the 'eternal runner-up'—he mentored a record number of Nobel laureates but did not receive the prize himself. He was also a talented pianist and music lover.

Quote: "What is quantum theory? It is philosophy expressed in the language of mathematics."

Links in the knowledge graph 1

Related laws

Balmer formula

Related scientists

Henri Poincaré Robert Hooke Johann Jakob Balmer James Clerk Maxwell Erwin Schrödinger Cecilia Payne-Gaposchkin Louis de Broglie Hendrik Lorentz

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Arnold Sommerfeld

Biography

Key discoveries

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