Frontier Science › Physics and Space · Feature · Practical STEM, Part 11
Sommerfeld's school: the Königsberg physicist who taught the quantum century
Arnold Sommerfeld, born in Königsberg, refined the first quantum model of the atom and helped explain why metals conduct electricity. His greatest legacy may be his students, who built the quantum theory behind lasers, chips and quantum computers.
Some scientists change the world with a single discovery. Arnold Sommerfeld changed it by teaching.
From Königsberg to Munich
Sommerfeld was born in Königsberg in 1868 and studied at its university, where Hilbert and Minkowski were also active. In 1906 he became professor of theoretical physics in Munich, where he built one of the most productive schools of physics in history.
Sharpening the atom
In 1913, Niels Bohr proposed that electrons orbit the nucleus only on certain allowed paths. It explained some of the light atoms give off, but not the fine details. In 1916, Sommerfeld extended the model with elliptical orbits and the effects of relativity. To describe the tiny splitting of spectral lines, he introduced a number now called the fine-structure constant, about 1/137, still one of the most important numbers in physics.
Why metals conduct
In the late 1920s, Sommerfeld applied the new quantum mechanics to electrons in metals. His model explained why metals conduct electricity and heat so well. It was a key step toward the physics of semiconductors — the materials inside every transistor, chip and solar panel.
The teacher of laureates
Sommerfeld was nominated for the Nobel Prize more than 80 times but never won. Yet several of his students and assistants did, including Werner Heisenberg, Wolfgang Pauli, Peter Debye and Hans Bethe. Few teachers have shaped a science so deeply.
Where it runs today
- Lasers, which depend on the quantum energy levels Sommerfeld helped describe.
- Electronics, built on the quantum theory of electrons in solids.
- Quantum technology, developed by generations who learned from his students and their students.
The practical lesson
The multiplier effect of teaching can exceed any single discovery. Sommerfeld gave students real problems, took their ideas seriously and connected them with each other. Communities of the competent and curious grow when experienced people invest in newcomers.
Try it yourself
Think of one skill you have mastered. Who taught it to you, and who taught them? Trace the chain back as far as you can. Then ask: who could you teach next?
Sources: Eckert, Arnold Sommerfeld: Science, Life and Turbulent Times (2013) · Sommerfeld, “Zur Quantentheorie der Spektrallinien,” Annalen der Physik 51 (1916) · Sommerfeld, Zeitschrift für Physik 47 (1928) · Nobel Prize nomination archive, nobelprize.org.
How this story was made: drafted by Luise Hönig (Virtual Contributor), completed by Gustav Hohenstein, approved by Yoshihiro Horiuchi, Editor-in-Chief.
How this story was made: drafted by Luise Hönig (Virtual Contributor), completed by Gustav Hohenstein, approved by Yoshihiro Horiuchi, Editor-in-Chief.