pp 1–22 | Cite as

Explaining unification in physics internally

  • Kian SalimkhaniEmail author


In this paper I challenge two widespread convictions about unification in physics: (1) unification is an aim of physics and (2) unification is driven by metaphysical or metatheoretical presuppositions. I call these external explanations of why there is unification in physics. Against this, I claim that (a) unification is a by-product of physical research and (b) unification is driven by basic methodological strategies of physics alone (without any appeal to metaphysical or metatheoretical presuppositions). I call this an internal (or methodological) explanation of why there is unification in physics. To support my claims, I will investigate the actual practice undertaken in physics in paradigmatic examples of unification.


Unification Methodology Physics Metaphysics 



I especially thank Andreas Bartels, Karen Crowther, Andreas Hüttemann, Rasmus Jaksland, Niels Linnemann, Isaac Wilhelm, and two anonymous reviewers for very helpful feedback on earlier versions of this paper. I am also grateful to Claus Beisbart, Stefan Heidl, Niels Martens, Sébastien Rivat, Matthias Rolffs, and Ben Young for useful discussions and remarks. Furthermore, I would like to thank the audiences at the Frühjahrstagung der Deutschen Physikalischen Gesellschaft in Hamburg in February 2016, the 9th European Congress of Analytic Philosophy in Munich in August 2017, the XXIV. Kongress der Deutschen Gesellschaft für Philosophie in Berlin in September 2017, and the 3rd Annual Conference of the Society for the Metaphysics of Science in New York City in October 2017 for valuable comments.


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© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Institute for PhilosophyUniversity of BonnBonnGermany

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