Hugo Tetrode


Hugo Martin Tetrode was a Dutch theoretical physicist who contributed to statistical physics, early quantum theory and quantum mechanics.
In 1912, Tetrode developed the Sackur–Tetrode equation, a quantum mechanical expression of the entropy of an ideal gas. Otto Sackur derived this equation independently around the same time. The Sackur–Tetrode constant, S0/R, is a fundamental physical constant representing the translational contribution to the entropy of an ideal gas at a temperature of 1 K and pressure of 100 kPa, where R is the gas constant.
From Amsterdam, Tetrode corresponded with Albert Einstein, Hendrik Lorentz and Paul Ehrenfest on quantum mechanics and wrote several influential papers on quantum mechanics which were published in the German physics journal Zeitschrift für Physik. In particular, the Machian notion that elementary particles only act on other elementary particles and not themselves was a key idea in the formulation of the Wheeler–Feynman time-symmetric theory.

Life

Hugo Tetrode was a member of the rich, prominent Tetrode family. He was the oldest of the three children of Pieter Johan Conrad Tetrode, who served as director of De Nederlandsche Bank from 1919 to 1934. Tetrode was born at Verlengde Vondelstraat 14 in what was then Nieuwer-Amstel but is now Vondelstraat 138 in Amsterdam. As a child, he lived on Amsterdam's canals, at Keizersgracht 573 and Herengracht 526.
Tetrode left for Germany in 1911 to study mathematics, physics and chemistry at the University of Leipzig, but returned to Amsterdam a year later. In 1912, at the age of 17, he published his first research paper in the German physics journal Annalen der Physik. He published a total of six scientific papers, all on topics of statistical physics and quantum mechanics.
He led a withdrawn life; it is said that Einstein and Ehrenfest once visited him in Amsterdam, but were sent away by a maid at the front door with the words Meneer ontvangt geen gasten.
Tetrode died at the age of 35, unmarried, after contracting a tuberculosis infection.

Publications