Restrained and modest - and nevertheless a revolutionary:Max Planck shook the world view of classical physics and laid a decisive foundation for modern science and technology.
On April 23, 1858 Max Planck is born in Kiel, the son of the law professor Wilhelm Planck. In 1867 the father received a chair in civil procedural law at the University of Munich and moved to the Bavarian capital with his wife and seven children. In Munich, the student Max Planck attended the Munich Maximiliansgymnasium, where he passed his Abitur at the age of 17. He is always an ambitious, conscientious and very good student. Encouraged by his mathematics teacher, it was here that he became enthusiastic about physics for the first time. But the high school student has other talents:Equipped with perfect pitch, he is interested in music, sings in choirs and plays the organ.
The undated photograph shows the young Max Planck.Therefore, choosing a subject for the young, multi-talented Planck is not easy. He vacillates between music, classics and physics. Finally, in the winter semester of 1874/75, he enrolled in the philosophical faculty of the University of Munich, where he attended physics and mathematics lectures. He joins the Academic Choral Society, sings, composes and acts in theatre.
Max Planck habilitated at the age of only 22
In the winter of 1877/78, Planck spent two semesters in Berlin at the Friedrich Wilhelm University, where he attended lectures by the physicists Hermann von Helmholtz and Gustav Kirchhoff. Back in Munich, he passed the teacher training exam for mathematics and physics. In 1879, at the age of only 21, he received his doctorate "On the second law of thermodynamics". Already at the age of 22 he habilitated and teaches as a private lecturer at the University of Munich. However, Planck's work has met with little interest in the professional world.
Breakthrough insights
Planck becomes in 1885 appointed associate professor for mathematical physics in Kiel. Four years later he moved to the University of Berlin as Gustav Kirchhoff's successor. At the beginning of his time in Berlin, Planck even dealt with problems of music theory at the Institute for Theoretical Physics. One of the guests in his lectures is Lise Meitner, who later collaborates with the chemist Otto Hahn on research into radioactivity.
"In Planck's lectures I initially struggled with a certain feeling of disappointment... Planck's lecture [seemed] for all its extraordinary clarity somewhat impersonal, almost sober. But I learned very quickly how little my first impression corresponded with Planck's true personality had to do. [...] He had a rare purity of mind and inner straightforwardness, which corresponded to his outward simplicity and plainness."Lise Meitner in:"Max Planck als Mensch", Naturwissenschaften 45, 17/1958, page 406
1894 The physicist Max Planck began researching heat radiation and discovered the natural constant h in 1899 - soon to be called Planck's constant. In 1900 Max Planck developed a law that describes the emission of electromagnetic energy by a black body, the "Planckian radiation law".
New energy quantity - hour of birth of quantum theory
For the first time, Niels Bohr's atomic model also takes into account findings from quantum mechanics.When justifying his formula, he has to introduce a new energy quantity ε. Because he recognizes that the radiation is not emitted continuously, but in energy packets, so-called quanta. ε is the amount of the quantum jump - and an expression of the break with the philosophical principle of the continuity of processes in nature, which applied in classical physics and philosophy up to that point and according to which there should be no sudden changes.
On December 14, 1900, he presented his findings at the meeting of the German Physical Society. This day is considered the hour of birth of quantum theory.
First skepticism - then the Nobel Prize
The theory is not only hotly debated in the professional world. But it was only with further interpretations by Albert Einstein and Bohr's atomic model that Planck's quantum theory gained more and more followers in the years that followed.
"A new scientific truth does not usually assert itself in such a way that its opponents are convinced and declare themselves educated, but rather by the fact that the opponents gradually die out and that the growing generation is familiar with the truth from the outset."Max Planck , Scientific Autobiography, Leipzig 1948, page 22
On November 13, 1919, Planck finally received the 1918 Nobel Prize in Physics for founding the quantum theory - "in recognition of the service he has rendered to the development of physics through his quantum theory," according to the jury.
From 1930 to 1937 he was President of the Kaiser Wilhelm Society, which set up and maintained non-university scientific research institutes.
Despite official bans, Planck organized 1935 a memorial service for his Jewish colleague Fritz Haber, who died in exile.
Serious strokes of fate
After the death of his first wife, Max Planck married Margarethe von Hoesslin in 1911.Planck's private life was initially very happy:in 1887 he married Marie Merck. The couple has four children. The family leads a lively musical and social life in the residential suburb of Grunewald in Berlin.
But in 1909 his wife died and in the following years all four children from his first marriage died. His eldest son was killed near Verdun, and in 1917 and 1919 the twin daughters died giving birth to their first children. His son Erwin, who belonged to the 20th of July Circle, was arrested and executed in January 1945. Despite the personal suffering, Planck unswervingly continued his scientific work. In 1911 he married a second time, Margarethe von Hoesslin. A son is born of this marriage.
1946:The Max Planck Society is founded
In 1946, Max Planck was the only German scientist to be a guest of the Royal Society at the Newton celebrations in London. He enjoys a high international reputation and in 1945 again becomes acting President of the Kaiser Wilhelm Society, which is now based in Göttingen. On September 11, 1946, the "Max Planck Society for the Advancement of Science in the British Zone" was founded as a successor. President is Otto Hahn, Planck becomes honorary president.
Today more than 80 Max Planck Institutes - and a number of Nobel Prize winners
Over the decades, the Max Planck Society has established itself as the leading German institution in basic research and maintains more than 80 institutes in addition to Germany, for example in the USA, the Netherlands and Italy. In addition to Stefan Hell, the Max Planck Society has produced a further 18 Nobel Prize winners.
In honor of Max Planck
Special stamp from 2008.In 1947 Planck received honorary citizenship of the city in which he was born and also spent some years of his childhood. He later taught as a professor of physics at the University of Kiel. Today a memorial stone commemorates the world-famous scientist. A grammar school and a street are named after him and there is a Max Planck room in Kiel City Hall.
Almost 90 years old, Max Planck died with great honor on October 4, 1947 in Göttingen.
"It is ideas that present the researcher with the problems that drive him to work incessantly and that open his eyes to correctly interpreting the results found. Without ideas, research becomes aimless and the energy expended on it is wasted in vain ."Max Planck, "Origin and Impact of Scientific Ideas"; Lecture given in 1933 in the Association of German Engineers. Berlin