On April 23, 1858, German theoretical physicist Max Planck was born, who originated quantum theory, which won him the Nobel Prize in Physics in 1918.
Max Karl Ernst Ludwig Planck was born in Kiel, but remained most of his school years in Munich. There he was introduced to the world of physics. After his graduation at the age of 16, he did not easily decide to study physics. His main interest belonged to musics. Max Planck had an absolute pitch, played the piano, cello and was an amazing singer. He even composed a few musical pieces during his time at school. However, he eventually decided not to become a professional musician due to the little career chances he foresaw.
At first, Planck enrolled at the University of Munich and later studied in Berlin. After receiving his doctorate, the young scientist became Privatdozent in Munich and then Associate Professor of Theoretical Physics in Kiel. In 1889, Planck succeeded Gustav Kirchhoff as Professor at the University of Berlin.
Planck’s earliest interests are known to be in the field of thermodynamics. On this topic and the subject of entropy and the theory of dilute solutions, he published his first works. Then radiation processes engaged Planck’s attention, and after some time of research he demonstrated that these are to be seen as electromagnetic in nature. This led Planck to the problem of the distribution of energy in the spectrum of full radiation. He managed to deduce the relationship between the energy and the frequency of radiation and completed a publication in which he announced “that the energy emitted by a resonator could only take on discrete values or quanta.” He introduced a fundamental physical constant now well known as the ‘Planck constant‘.
On December 14, 1900, Max Planck reported his newest research results, that demonstrated the relations of radiation. Today this day is known as the birth hour of quantum physics, but back then nobody knew what they really had in front of them. In 1905, Planck read Albert Einstein’s publication “On the Electrodynamics of Moving Bodies”. Einstein was still pretty unknown in the scientific community, but Planck, who also researched on special relativity at this time, was able to convince his colleagues of Einstein’s theories. It was in the same year, that through Einstein’s work, Max Planck noticed a mistake in his calculations and finally managed to establish further versions of his quantum theory, in oder to combine Planck’s law with classical physics.
After the first World War, Max Planck and Fritz Haber established the Notgemeinschaft der Deutschen Wissenschaft (Emergency Organization of German Science). The organisation aimed at providing financial support for scientific research. At the end of the 1920s Bohr, Heisenberg and Pauli had worked out the Copenhagen interpretation of quantum mechanics, but it was rejected by Planck, and by Schrödinger, Laue, and Einstein as well. Planck expected that wave mechanics would soon render quantum theory unnecessary.
During World War II, Planck continued working in Berlin. However, the increasing Allied bombing missions against Berlin forced Planck and his wife to temporarily leave the city and live in the countryside. Eventually, his home in Berlin was completely destroyed. Following the attempted assassination of Hitler in the 20 July (1945) plot, Planck’s son Erwin was arrested and killed by the Gestapo. After the war, Max Planck and his wife were brought to a relative in Göttingen. There he dies on October 4, 1947.
Renato Renner: Interpretations of quantum theory
References and Further Reading:
-  Max Planck at the Nobel Prize Website
-  Max Planck Website [German]
-  Albert Einstein revolutionized Physics
-  Standing on the Shoulders of Giants – Sir Isaac Newton
-  A Life of Discoveries – the great Michael Faraday
-  Articles related to Albert Einstein
-  Max Planck at Wikidata
-  Max Planck Timeline via Wikidata