Martin Jähnert

Visiting Postdoctoral Fellow
Visiting Postdoctoral Fellows are early career scholars who are ordinarily no more than five years past the granting of the doctorate and who are either externally financed or receive a Fellowship rather than a contract from the MPIWG.
Department I
PhD, Doctoral Student, Technische Universität Berlin
6. Mai 2017 to 31. Mai 2019

In his PhD project Martin Jähnert studies the development of the correspondence principle in the old quantum theory as a process of adaptive reformulation. By looking at different uses of the principle the project aims to understand how physicists came to work with the principle and how the principle was shaped through its applications. The project studies this process of adaptive reformulation in the context of the dispersion of the correspondence principle throughout the networks of the old quantum theory and its simultaneous transfer into different fields of research  (e.g. atomic and molecular spectroscopy, dispersion, and collision processes). Thereby Jähnert shows how the principle became one of the most fruitful research tools of the old quantum theory.

In previous work with Christoph Lehner, Martin Jähnert has studied the early debates on the interpretation of quantum mechanics and its interplay with the development of the theory. From this perspective, the interpretational debate was understood as a reflection on the role of pictures and models within the research process. Their work aimed to clarify how physicists dealt with the methodological and epistemological challenges arising from the development of quantum mechanics.

Selected publications: 

Blum, A. S., Jähnert, M., Lehner, C., & Renn, J. (2017). Translation as heuristics: Heisenberg’s turn to matrix mechanics. Studies in History and Philosophy of Modern Physics, 60, 3-22. doi:10.1016/j.shpsb.2017.03.005.


Jähnert, M. (2015). Practising the correspondence principle in the old quantum theory: Franck, Hund and the Ramsauer effect. In F. Aaserud, & H. Kragh (Eds.), One hundred years of the Bohr atom: proceedings from a conference (pp. 200-216). Copenhagen: Det Kongelige Danske Videnskabernes Selskab.


Jähnert, M. (2013). Review of: Carson, Cathryn, Alexei Kojevnikov and Helmuth Trischler: Weimar culture and quantum mechanics: selected papers by Paul Forman and contemporary perspectives on the Forman thesis. London: Imperial College Press [u.a.] 2011. Berichte zur Wissenschaftsgeschichte, 36(4), 384-385.


Jähnert, M. (2013). The correspondence idea in the early Bohr atom 1913-1915. Annalen der Physik, 525(10-11), A155-A158.


Jähnert, M. (2012). 'Revisiting the 1927 Solvay conference and the early interpretation of quantum mechanics'. Essay review of Bacciagaluppi, Guido and Antony Valentini: Quantum theory at the crossroads: reconsidering the 1927 Solvay conference. Cambrigde: Cambrigde Univ. Press 2009. Metascience, 21(1), 125-129.

The Correspondence Principle in Practice: Its Use and Dispersion in the Old Quantum Theory
100 years of the Bohr atom, Copenhagen
Transferring and Practicing the Correspondence Principle in the Old Quantum Theory: Friedrich Hund and the Ramsauer effect
Spring meeting of the Deutsche Physikalische Gesellschaft (DPG) - "Wissenstransfer in der Geschichte der Physik", Jena
From Continuity to Discontinuity: The Correspondence Principle and the Transformation of Mechanics
AIP-Washington: Continuity and Discontinuity in the Physical Sciences Since the Enlightenment: A Conference for Graduate Students and Early-Career Scholars
Pictures and Principles. Heuristics in the Early Interpretational Debate on Quantum Mechanics
Workshop of the Deutsche Physikalische Gesellschaft, “Heuristics in Physics”, Bad Honnef
Kopenhagener Deutung und dialektischer Materialismus
Annual meeting of the Germany Society for the History of Medicine, Sciences, and Technology (DGMNT), Hanover