Quantum_ Einstein, Bohr and the Great Debate About the Nature of Reality - Manjit Kumar [9]
German universities were state institutions. Extraordinary (assistant) and ordinary (full) professors were civil servants appointed and employed by the ministry of education. In 1880 Planck became a privatdozent, an unpaid lecturer, at Munich University. Employed neither by the state nor the university, he had simply gained the right to teach in exchange for fees paid by students attending his courses. Five years passed as he waited in vain for an appointment as an extraordinary professor. As a theorist uninterested in conducting experiments, Planck's chances for promotion were slim, as theoretical physics was not yet a firmly established distinct discipline. Even in 1900 there were only sixteen professors of theoretical physics in Germany.
If his career was to progress, Planck knew that he had 'to win, somehow, a reputation in the field of science'.30 His chance came when Göttingen University announced that the subject for its prestigious essay competition was 'The Nature of Energy'. As he worked on his paper, in May 1885, 'a message of deliverance' arrived.31 Planck, aged 27, was offered an extraordinary professorship at the University of Kiel. He suspected it was his father's friendship with Kiel's head of physics that had led to the offer. Planck knew there were others, more established than he, who would have expected advancement. Nevertheless, he accepted and finished his entry for the Göttingen competition shortly after arriving in the city of his birth.
Even though only three papers were submitted in search of the prize, an astonishing two years passed before it was announced that there would be no winner. Planck was awarded second place and denied the prize by the judges because of his support for Helmholtz in a scientific dispute with a member of the Göttingen faculty. The behaviour of the judges drew the attention of Helmholtz to Planck and his work. After a little more than three years at Kiel, in November 1888, Planck received an unexpected honour. He had not been first, or even second choice. But after others had turned it down, Planck, with Helmholtz's backing, was asked to succeed Gustav Kirchhoff at Berlin University as professor of theoretical physics.
In the spring of 1889, the capital was not the city Planck had left eleven years earlier. The stench that always shocked visitors had disappeared as a new sewer system replaced the old open drains, and at night the main streets were lit by modern electric lamps. Helmholtz was no longer head of the university's physics institute but running the PTR, the majestic new research facility three miles away. August Kundt, his successor, had played no part in Planck's appointment, but welcomed him as 'an excellent acquisition' and 'a splendid man'.32
In 1894 Helmholtz, aged 73, and Kundt, only 55, both died within months of each other. Planck, only two years after finally being promoted to the rank of ordinary professor, found himself as the senior physicist at Germany's foremost university at just 36. He had no choice but to bear the weight of added responsibilities, including that of adviser on theoretical physics for Annalen der Physik. It was a position of immense influence that gave him the right of veto on all theoretical papers submitted to the premier German physics journal. Feeling the pressure of his newly elevated position and a deep sense of loss at the deaths of his two colleagues, Planck sought solace in his work.
As a leading member of Berlin's close-knit community of physicists, he was well aware of the ongoing, industry-driven blackbody research programme of the PTR. Although thermodynamics was central to a theoretical analysis of the light and heat radiated by a blackbody, the lack of reliable experimental data had stopped Planck from trying to derive the exact form of Kirchhoff's unknown equation. Then a breakthrough by an old friend at PTR meant that he could no longer avoid the blackbody problem.
In February 1893, 29-year-old Wilhelm Wien discovered a simple mathematical relationship that described the effect of a change in temperature