Molecules and Entropy
Restlessness was the story of his life and work. Ludwig Boltzmann saw the physical world as a perpetually agitated molecular chaos; and, like the molecules, he never found rest himself. He moved from one academic post to another seven times during his career of almost forty years. The chronology goes like this: two years (1867–69) at the University of Vienna as an assistant professor; four years (1869–73) as an assistant professor of mathematical physics at the University of Graz; back to Vienna for three years (1873–76) as a professor of mathematics; to Graz again for fourteen years (1876–90) as a professor of experimental physics; four years (1890–94) as a professor of theoretical physics at the University of Munich; a second return to Vienna for four years (1894–1900), this time as a professor of theoretical physics; two years in Leipzig (1900–1902) as a professor of theoretical physics; and a third and final return to Vienna to succeed himself in the chair still unoccupied since his departure two years earlier.
These were not forced departures. From the early 1870s on, Boltzmann was famous in the scientific world and much in demand. To entice him to return from Munich to Vienna, the Austrian minister of culture had to offer him the highest salary then paid to any Austrian university professor. Competing faculties described him as the “uncontested first representative” of theoretical physics “recognized as such by all nations,” and “the most important physicist in Germany and beyond.” In this job market, Boltzmann was not above some hard bargaining with the appropriate ministries. Late in his life he was negotiating for his next move soon after he had completed the last one. The Vienna authorities finally decided enough was enough: they would take him back (for the third time) only if he would give his word that he would never take another job outside Austria.
But Boltzmann's restlessness was driven by more than salaries and the other things he complained about in his correspondence, such as the quality of the students and German cooking. He moved incessantly because the polar opposites of his personality would give him no peace. He joked that these polarities were