Is There Any Good History of Quantum Physics, and if so, Should We Care?

was the title of a lecture given in English at Freiburg's Physics Colloquium. The speaker was Prof. Arne Schirrmacher of the Berlin Humboldt University.

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Quantum physics will celebrate its 100th anniversary next year, and Prof. Schirrmacher is correct in questioning its history.

It may be important for historians, but I couldn't care less whether the letter h used for Planck's constant (Wirkungsquantum) initially stood for Hilfsgröße (auxiliary variable).

More interesting is to analyze Heisenberg's revelation - when staying on Helgoland from June 8 to 18, 1925 - on how to solve quantum mechanical problems with the help of energy matrices. Ηere is Heisenberg's personal account translated from his autobiography Der Teil und das Ganze (1969):

"So I concentrated my work more and more on the question of the conservation of energy and one evening, I was able to determine the individual terms in the energy table, or as it is expressed today, in the energy matrix, using calculations that are quite complicated by today's standards. When the first terms confirmed energy conservation, I got so excited that I kept making mistakes in the following calculations. As a result, it was almost three o'clock in the morning before the final result of the calculations was in front of me. Energy conservation had been valid in all its parts, and - since all this had come out by itself, without any acrobatics, so to speak - I could no longer doubt the mathematical consistency and coherence of quantum mechanics appearing in outlines. At first, I was deeply shocked. I had the feeling that I was looking through the surface of atomic phenomena to a deep underlying ground of strange inner beauty. I was almost dizzy at the thought that I was now supposed to follow this wealth of mathematical structures that nature had spread out before me. I was so excited that I couldn't think about sleep. So I left the house in the early dawn and went to the southern tip of the Oberland, where a solitary rock tower jutting out into the sea had always awakened my desire to try climbing. I managed to climb the tower without difficulty and awaited the sunrise at the top."

It is correct to accuse Carlo Rovelli of Geschichtsklitterung (historical distortion) when he writes in his best-selling book Helgoland:

"And here he* had the idea. An idea that could only be had with the unfettered radicalism of the young. The idea that would transform physics in its entirety - together with a whole of science and our very conception of the world. An idea, I believe, that humanity has not yet fully absorbed."
*young Heisenberg

Rovelli was carried away and went overboard. Heisenberg didn't invent or discover quantum mechanics on Helgoland. However, he found a - as he admits, clumsy - method to calculate energy states for quantum systems while away from his Physics Institute in Göttingen, away from his Professor Max Born and his colleague Pascual Jordan.

Prof. Schirrmacher had the argument that while Heisenberg was on Helgoland, his colleagues published About the quantum theory of aperiodic processes: Born, M., Jordan, P. Zur Quantentheorie aperiodischer Vorgänge. Z. Physik 33, 479–505 (1925). The paper was received at the Springer Publishing House on June 11, 1925.

Heiseberg‘s Helgoland paper On the quantum-theoretical reinterpretation of kinematic and mechanical relationships: Heisenberg, W. Über quantentheoretische Umdeutung kinematischer und mechanischer Beziehungen.. Z. Physik 33, 879–893 (1925), was received on July 29, 1925.

This proves that Götingen was the productive center for quantum mechanics then. The coronation of the teamwork was the famous "drei Männer Arbeit": Born, M., Heisenberg, W. & Jordan, P. Zur Quantenmechanik II. Z. Physik 35, 557–615 (1926), received on November 16, 1925. The paper is generally regarded as the "birth certificate" of matrix mechanics. Needless to say, Schrödinger's differential equation of 1926 made the calculations of quantum states "easier."


The Nachsitzung (follow-up session) to the colloquium was a dinner at a Freiburg restaurant. My discussion with Prof. Schirrmacher revolved around German physicist Philipp Lenard. He got the Nobel Prize in 1907 and was director of the Physics Institute in Heidelberg.

Lenard argued that: "Science, like everything that humans produce, is racial, blood-related."

Why was Lenard an anti-Semite when he idolized his Jewish teacher, Heinrich Hertz? Prof. Schirrmacher suspected he was frustrated because no significant work was coming from his new and large Heidelberg Philipp-Lenard Institute. As compensation, he surfed on the "völkisch" wave.

However, Lenard had already argued with Einstein as early as 1920 at the Congress of Natural Scientists and Physicians in Bad Nauheim. Under Max Planck's chairmanship, he criticized the relativity theory as unanschaulich (unclear).

Lenard's new institute was only inaugurated in 1935 with a speech by his colleague, Nobel Prize winner, President of the Physikalisch-Technische Reichsanstalt, and anti-Semite Johannes Stark:

"Einstein's theories of relativity were basically nothing more than an accumulation of artificial formulas based on arbitrary definitions and transformations of space and time coordinates. The sensation and publicity of Einstein's theory of relativity were followed by Heisenberg's theory of matrices and Schrödinger's so-called wave mechanics, the one as opaque and formalistic as the other. Despite accumulating such theoretical literature in piles, it did not provide any significant insight into reality in physics."

In January 1936, an article appeared in the Nazi journal Völkischer Beobachter with the title Deutsche Physik und Jüdische Physik. It was Philipp Lenard who had, in his 4-volume textbook on physics published in 1935, distinguished between German Physics and Jewish Physics. He wrote in the preface:

"With the end of the war in 1918, when the Jews became dominant and set the tone in Germany, Jewish physics in all its peculiarity suddenly emerged like a flood ... To characterize it briefly, the activity of its most outstanding representative, the pure-blooded Jew A. Einstein, is here recalled. His 'theories of relativity 'were intended to reshape and dominate the whole of physics, but they have now completely failed in the face of reality. They probably never wanted it to be true. The Jew conspicuously lacks an understanding of truth, for more than just an apparent correspondence with reality independent of human thought; this contrasts the Aryan researchers' irrepressible and anxious desire for truth." Nazi jargon of the worst kind.

In July 1937, the other Nazi physicist Johannes Stark published an essay in the SS newspaper Das Schwarze Korps "Weiße Juden in der Wissenschaft" and identified Heisenberg as a White Jew.

In response, Heisenberg wrote to Heinrich Himmler, Reichsführer SS, "I must ask you for a fundamental decision: If Mr. Stark's views coincide with those of the government, I will naturally ask for my dismissal. But if this is not the case, as I have been expressly assured by the Reich's Ministry of Education, in that case, as Reichsführer SS, I ask you for adequate protection against such attacks in the newspaper under your command."

The Reichsführer buckled, but in a letter to Reinhard Heydrich, the second man in the SS, Himmler wrote, "We cannot afford to kill this young man."

You may read the whole story in German here.
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