Origins & Early Life

Paul Ehrenfest (Austrian German: [ˈpaʊl ˈeːrənfɛst]; 18 January 1880 – 25 September 1933) was an Austrian theoretical physicist who made major contributions to statistical mechanics and its relation to quantum mechanics, including the theory of phase transition and the Ehrenfest theorem. He befriended Albert Einstein on a visit to Prague in 1912 and became a professor in Leiden, where he frequently hosted Einstein. Suffering from depression, in 1933 Ehrenfest killed his disabled son, Wassik, and then himself. Paul Ehrenfest was born on 18 January 1880 in Vienna to Jewish parents, who were originally from Loštice in Moravia (now part of the Czech Republic).

Pivotal Works & Achievements

His parents, Sigmund Ehrenfest and Johanna Jellinek, managed a grocery store. Ehrenfest excelled in grade school but did not do well at the Akademisches Gymnasium, his best subject being mathematics. After transferring to the Franz Josef Gymnasium, his marks improved. In 1899, he passed the final exams. He majored in chemistry at the Vienna Institute of Technology, but took courses at the University of Vienna, in particular from Ludwig Boltzmann on his kinetic theory of thermodynamics.

Enduring Legacy & Impact

These lectures had a profound...

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