Physics in Perspective

, Volume 17, Issue 3, pp 236–250 | Cite as

Quantum Explorers: Bohr, Jordan, and Delbrück Venturing into Biology

  • Leyla Joaquim
  • Olival FreireJr.
  • Charbel N. El-Hani


This paper disentangles selected intertwined aspects of two great scientific developments: quantum mechanics and molecular biology. We look at the contributions of three physicists who in the 1930s were protagonists of the quantum revolution and explorers of the field of biology: Niels Bohr, Pascual Jordan, and Max Delbrück. Their common platform was the defense of the Copenhagen interpretation in physics and the adoption of the principle of complementarity as a way of looking at biology. Bohr addressed the problem of how far the results reached in physics might influence our views about life. Jordan and Delbrück were followers of Bohr’s ideas in the context of quantum mechanics and also of his tendency to expand the implications of the Copenhagen interpretation to biology. We propose that Bohr’s perspective on biology was related to his epistemological views, as Jordan’s was to his political positions. Delbrück’s propensity to migrate was related to his transformation into a key figure in the history of twentieth-century molecular biology.


Quantum mechanics molecular biology complementarity principle Niels Bohr Pascual Jordan Max Delbrück 



We would like to thank the Max Planck Institute for the History of Science (MPIWG) and the American Institute of Physics (AIP) for financial and structural support and also the Brazilian agency CAPES (Coordination for the Improvement of Higher Education Personnel) for funding the entire project. We are also thankful to the editors for the careful review and editing of this paper.


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Copyright information

© Springer Basel 2015

Authors and Affiliations

  • Leyla Joaquim
    • 1
  • Olival FreireJr.
    • 1
  • Charbel N. El-Hani
    • 2
  1. 1.Instituto de FísicaUniversidade Federal da BahiaOndina, SalvadorBrazil
  2. 2.Instituto de BiologiaUniversidade Federal da BahiaOndina, SalvadorBrazil

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