An Homage to Otto Stern

This chapter outlines an International Symposium held at Frankfurt on 1–5 September 2019. It marked the centennial of quantitative experiments with molecular beams, pioneered by Otto Stern. The European Physical Society declared Stern’s original laboratory a Historic Site, the fifth in Germany. As a graduate student in 1955, I learned about Otto Stern (1888–1969) and the impact of his molecular beams on quantum physics. I was intrigued and undertook crossed-beam experiments at Berkeley. In 1960 Otto came to a seminar that I gave. Later I met him, and heard some of his stories. The rest of the chapter describes his Nobel Prize and other Fests. In 1958 his long-term colleague, Immanuel Estermann, organized a celebration and Festschrift for Otto’s 70th birthday. In 1988, as a guest editor, I organized a Festschift for the centennial of Otto’s birth. That year, the German Physical Society established the Stern-Gerlach Prize as its highest award for experimental physics. Bretislav Friedrich and I wrote three papers about Stern. Since 2000, Horst Schmidt-Böcking at Frankfurt and colleagues have produced historical articles, along with a book about Otto, edited and bound all of his research papers into books, and diligently pursued letters to and from Otto, collecting them into large volumes.

“I didn’t really think about it ” (M. Planck and the Quantum Revolution)

Introduction. In the philosophy of science great attention is traditionally paid to theoretical knowledge. However, scientific theories are considered, as a rule, as something already formed, whereas the analysis of the birth and formation of the theory plays a much smaller role. Among the various issues that arise at the intersection of philosophy and history of science the great attention of researchers is attracted by the question about the nature of scientific revolutions. In this work, the question is studied by examing the Planck’s discovery– whether a conservative in science to make a scientific revolution?Methodology and sources. Methodologically, the work is based on historical and scientific analysis of primary sources and research literature. Results and discussion. The paper according the results of the study of primary sources shows that the only desire Planck in his study of blackbody radiation and the only justification for his “Akt der Verzweilung” (Act of delays) was to obtain a “correct” mathematical formula “at any price”. As for the scientific revolution on 14 December 1900 – date of Planck’s speech at a meeting of the German physical society report on “the Theory of the distribution of the radiation energy of the normal spectrum” – that is the result of later historical reconstruction. Moreover, this “revolution” in 1900, and in subsequent years remained unnoticed by anyone, including Planck himself. Thus, the result of the study is a new look at the specifics of the contribution of the scientist standing on conservative scientific positions in the scientific revolution.Conclusion. Under certain circumstances, the main of which are the character of the task and readiness of the researcher, at least in part to “sacrifice principles” (or to simulate a departure from tradition) for the sake of formal success, the conservator may contribute to the further development of events that will eventually lead to the scientific revolution.