Heritage · Legacy
Max Planck Legacy
German theoretical physicist (1858–1947) who introduced energy quanta in 1900, launching quantum theory, and won the 1918 Nobel Prize in Physics.Written to last.
By Confinity Heritage Editorial · Updated 2026-07-31 · 6-minute readQuiet tools, kept out of the way.
Max Karl Ernst Ludwig Planck was the German theoretical physicist who, almost against his own instincts, opened the quantum age. In December 1900 he proposed that a radiating body releases energy not in a smooth flow but in discrete packets he called quanta, a break with classical physics so sharp that he later described it as an act of desperation. The idea seeded quantum mechanics, one of the two pillars of modern physics, and earned him the Nobel Prize in Physics for 1918 (Nobel Prize).
Planck was born on 23 April 1858 in Kiel, then part of the Duchy of Holstein, into a family of scholars and jurists; his father, Johann Julius Wilhelm Planck, was a professor of law (Wikipedia). When Planck was nine the family moved to Munich, where he attended the Maximilian Gymnasium and showed early gifts in music as well as mathematics. He entered the University of Munich in 1874, at sixteen. One story from those years has his teacher Philipp von Jolly advising him against physics, on the grounds that almost everything in the field had already been discovered (MacTutor).
He was not persuaded. After a year in Berlin studying under Hermann von Helmholtz and Gustav Kirchhoff, and reading Rudolf Clausius on thermodynamics on his own, Planck returned to Munich and took his doctorate in July 1879, at twenty-one, with a dissertation on the second law of thermodynamics (MacTutor). Thermodynamics and the meaning of entropy would occupy him for the next two decades. He taught at Munich and Kiel before being called to the University of Berlin in 1889 to succeed Kirchhoff, becoming a full professor there in 1892 (Britannica).
By the late 1890s Planck was drawn to a stubborn puzzle: the spectrum of light given off by a heated black body. The best classical theories described part of the curve but failed badly at high frequencies, a mismatch later nicknamed the ultraviolet catastrophe. Planck first found a formula that matched the measurements exactly, then spent months trying to justify it (Britannica).
The justification forced a strange assumption. Energy, Planck argued, could be emitted or absorbed only in finite units proportional to frequency, written as E = hν, where h was a new constant of nature now known as Planck's constant. He presented the result to the German Physical Society in Berlin on 14 December 1900, a date often taken as the birth of quantum theory (Wikipedia). Planck himself long treated the quantum as a mathematical device rather than a physical fact. It was Albert Einstein who, in 1905, took the idea literally to explain the photoelectric effect. The Nobel Prize for 1918 recognised Planck "for his discovery of energy quanta" (Nobel Prize).
Planck's constant proved to be one of the fundamental numbers of physics, and the quantum idea he reluctantly introduced was developed by Niels Bohr, Werner Heisenberg and Erwin Schrödinger into the quantum mechanics that now underlies chemistry, electronics, lasers and semiconductors. Planck was also an early champion of Einstein's work, defending the theory of relativity and helping bring Einstein to Berlin (Britannica).
His personal life was marked by repeated loss. His first wife, Marie Merck, died in 1909; his son Karl was killed at Verdun in 1916; and his twin daughters, Grete and Emma, both died in childbirth, in 1917 and 1919 (Wikipedia). Planck remained in Germany through the Nazi years, serving as president of the Kaiser Wilhelm Society from 1930 to 1937 and trying, with little success, to shield German science and Jewish colleagues from the regime. His son Erwin was implicated in the July 1944 plot against Hitler and executed on 23 January 1945 (Wikipedia). Planck died in Göttingen on 4 October 1947. The following year the Kaiser Wilhelm Society was refounded in his name as the Max Planck Society, today one of the leading research organisations in the world (Max Planck Society).
Planck was seventy-five in 1933 and the most senior figure in German science, president of the Kaiser Wilhelm Society. He chose to stay, on the argument that somebody had to preserve the institutions until the regime passed, and he sought an audience with Hitler to argue against the dismissal of Jewish scientists. It went badly and he did not try again. Colleagues who left, and colleagues who stayed, have both criticised the decision ever since, and he criticised it himself.
The cost was personal and it was total. His first wife died in 1909. His eldest son was killed at Verdun in 1916. Both his twin daughters died in childbirth, in 1917 and 1919. His house in Berlin was destroyed by bombing in 1944 along with his papers and his correspondence.
Then in 1945 his surviving son Erwin, a senior civil servant, was arrested for involvement in the July plot against Hitler, and executed in January of that year after Planck had petitioned for his life. Planck said afterwards that Erwin had been his most precious possession and that something in him had died with him.
He lived until October 1947. The Kaiser Wilhelm Society was renamed for him in 1948, and the Max Planck Society now runs eighty-odd institutes.
Planck's life shows how one careful idea can change what physics is able to explain, and how discovery often arrives wrapped in doubt rather than certainty. We keep his record because it holds both the work and the man who carried it, including the losses that ran alongside his fame.
Early life
The quantum revolution of 1900
Legacy
What staying cost him
What the record holds
References and resources
Timeline
- 1858Born in Kiel, in the Duchy of Holstein
- 1879Earns his doctorate at the University of Munich
- 1889Called to the University of Berlin, succeeding Kirchhoff
- 1900Introduces energy quanta on 14 December
- 1918Awarded the Nobel Prize in Physics
- 1930Becomes president of the Kaiser Wilhelm Society
- 1947Dies in Göttingen