Epistemology of Physics

Subproject a: The Development and Unity of Physics: Epistemological Motives and Their Historical Change

This book project investigates the question how physics "works" epistemically: what counts as a good explanation in physics, what kind of relations hold between different explanations (between different theories, between different models), and are there historical shifts or changes in these relations?

The first—historical—part of the book introduces important stages in the history of physics by focussing on three major epochs. The chapter on antiquity discusses, among other things, the origin of the term "physics" as well as first attempts towards what might be called an "elementarism" about material reality. The chapter on the early modern period addresses most notably aspects of an increasing mathematisation of physics. And the chapter on the nineteenth and twentieth century highlights the development of classical field theory and of quantum physics and the resulting loss of the intuitiveness of physics.

The second—systematic—part of the book critically reflects the historical changes in the role and relevance of experiments and predictions in physics. There is a detailed discussion of how new physical concepts and theories are formed and of how these formation processes changed in character since antiquity. This leads to a discussion also of the notions of causality and objectivity as well as to questions about reductions between theories and about a possible unity of physics. Moreover, three general explicatory strategies are identified which can be found and which keep more or less stable throughout the whole history of physics. One of these strategies might be called "mereological" and is devoted to finding ultimate material constituents. A different strategy, which might be entitled "explanatory", searches for the "initiators" or causes of physical events (often in terms of forces). And then there is the search for a unified framework of representation. This strategy might be called "holistic" and it is, of course, often related to the mathematisation of physics. Last but not least, connections and transitions between these three strategies become transparent with the help of a further central concept employed in physics, namely that of symmetry.

As compared to other introductory works, the focus of the present book is not on innerphilosophical debates about, for instance, the metaphysical status of spacetime or the opposition between a nominalism and a realism regarding natural laws. Neither does it focus on popular presentations of modern physical theories. Instead, the book's aim is to provide insights into a certain methodological and epistemological unity of physics by showing the continuities and developments in the formation of theories and in the predominant explicatory strategies.

Participant: PD Dr. Dr. Norman Sieroka

Publications:

N. Sieroka (2014): external pagePhilosophie der Physik (series: C.H. Beck Wissen). Beck Verlag, München.
Rezensionen in: Spektrum der Wissenschaft, 2/2015, pp. 88-89 – external pageonline

Sterne und Weltraum, 6/2015, pp. 96-97

Physik Journal 14 (2), 2015, p. 64

VSMP Bulletin 127, 2015, p. 5

Bunsenmagazin 17 (6), 2015, p. 242

Physik in unserer Zeit 46 (6), 2015, p. III

Subproject b: Epistemic Issues in Particle Physics

This project critically evaluates the different and empirically successfull theoretical approaches to contemporary quantum field theory. The current state of physics is discussed against the backdrop of philosophy, especially of a philosophy of symbols as first developed by Hermann von Hemholtz and Heinrich Hertz. It is no coincidence that these symbolic approach appeared together in the second half of the 19th century with the Maxwellian theory of electromagnetism. The new epistemological problems which emerged with classical field theory, and which resisted mechanical interpretation, become even more pressing today under the interpretation of quantum field theory.

The first major philosopher who further developed and defended such a symbolic understanding of field theories and of quantum physics was Ernst Cassirer. His work is of relevance for the present project also because it allows to see connections to current (though less transcendentally laden) debates in analytic philosophy of science, such as the ongoing debates about structural realism.

A further aim of this project is to provide the interested non-specialist with an account of the concepts of quantum field theory and their connection to experimentation. In particular, this includes a critical assessment and discussion of experiments conducted recently at CERN. It also includes a discussion of the inherent limits of these experiments and of the popular hopes and fears as fueled by the media.

Participants:
PD Dr. Dr. Norman Sieroka
external pageProf. em. Dr. Hans Günter Dosch (Theoretische Physik, Universität Heidelberg)
external pageProf. em. Dr. Volkhard F. Müller (Theoretische Physik, Universität Kaiserslautern)

Publications:

H.G. Dosch, V.F. Müller, N. Sieroka (2009): Symbolic Constructions in Quantum Field Theory. In: Constituting Objectivity: Transcendental Approaches of Modern Physics (The Western Ontario Series in Philosophy of Science), ed. by M. Bitbol, P. Kerzsberg and J. Petitot. Springer, Dordrecht, pp. 403-413.
N. Sieroka (2008): Tückenreiche Analogien (Interview). connect (Alumni Magazin der ETH), Nr.15, November 2008.
N. Sieroka (2008): Der Urknall regt die Fantasie an: Die Angst vor dem Experiment des CERN. Tagesanzeiger, 23.09.2008.
N. Sieroka (2008): Das CERN auf den Spuren Gottes? Horizonte, 14.09.2008.
N. Sieroka (2008): Die Grenzen des Wissens: Religion und Philosophie werden die neusten Forschungen überleben. bazkultur (Kulturmagazin der Basler Zeitung), 30.07.2008.
N. Sieroka (2007): Hertzian Pictures of Quantum Field Theory. Philosophia Naturalis 44 (1), pp. 88-113.
H.G. Dosch, V.F. Müller, N. Sieroka (2005): external pageQuantum Field Theory in a Semiotic Perspective. Springer Verlag, Heidelberg.