John Ellis McTaggart defended an idealistic view of time in the tradition of Hegel and Bradley. His famous paper makes two independent claims (McTaggart1908): First, time is a complex conception with two different logical roots. Second, time is unreal. To reject the second claim seems to commit to the first one, i.e., to a pluralistic account of time. We compare McTaggarts views to the most important concepts of time investigated in physics, neurobiology, and philosophical phenomenology. They indicate that a unique, (...) reductionist account of time is far from being plausible, even though too many conceptions of time may seem unsatisfactory from an ontological point of view. (shrink)
Astroparticle physics is a recent sub-discipline of physics that emerged from early cosmic ray studies, astrophysics, and particle physics. Its theoretical foundations range from quantum field theory to general relativity, but the underlying “standard models” of cosmology and particle physics are far from being unified. The paper explores the pragmatic strategies employed in astroparticle physics in order to unify a disunified research field, the concept of observation involved in these strategies, and their relations to scientific realism.
The article investigates the way in which Peter Mittelstaedt has been contributing to the philosophy of physics for half a century. It is shown that he pursues a path between rationalism and empiricism in the sense of Erhard Scheibe’s philosophy of the physicists. Starting from Kant’s a priori he gives a rational reconstruction of the conceptual revolutions of 20th century physics. The central topic of his philosophy of physics is the quest for semantic self-consistency, which for quantum mechanics is a (...) hard nut to crack. (shrink)
Depending on different positions in the debate on scientific realism, there are various accounts of the phenomena of physics. For scientific realists like Bogen and Woodward, phenomena are matters of fact in nature, i.e., the effects explained and predicted by physical theories. For empiricists like van Fraassen, the phenomena of physics are the appearances observed or perceived by sensory experience. Constructivists, however, regard the phenomena of physics as artificial structures generated by experimental and mathematical methods. My paper investigates the historical (...) background of these different meanings of phenomenon in the traditions of physics and philosophy. In particular, I discuss Newton’s account of the phenomena and Bohr’s view of quantum phenomena, their relation to the philosophical discussion, and to data and evidence in current particle physics and quantum optics. (shrink)
Studying astroparticle physics sheds new light on scientific explanation and on the ways in which cosmology is empirically underdetermined or not. Astroparticle physics extends the empirical domain of cosmology from purely astronomical data to “multi-messenger astrophysics”, i.e., measurements of all kinds of cosmic rays including very high energetic gamma rays, neutrinos, and charged particles. My paper investigates the ways in which these measurements contribute to cosmology and compares them with philosophical views about scientific explanation, the relation between theory and data, (...) and scientific realism. The “standard models” of cosmology and particle physics lack of unified foundations. Both are “piecemeal physics” in Cartwright's sense, but contrary to her metaphysics of a “dappled world” the work in both fields of research aims at unification. Cosmology proceeds “top-down”, from models to data and from large scale to small-scale structures of the universe. Astroparticle physics proceeds “bottom-up”, from data taking to models and from subatomic particles to large-scale structures of the universe. In order to reconstruct the causal stories of cosmic rays and the nature of their sources, several pragmatic unifying strategies are employed. Standard views about scientific explanation and scientific realism do not cope with these “bottom-up” strategies and the way in which they contribute to cosmology. In addition it has to be noted that the shift to “multi-messenger astrophysics” transforms the relation between cosmological theory and astrophysical data in a mutually holistic way. (shrink)
Does incommensurability threaten the realist’s claim that physical magnitudes express properties of natural kinds? Some clarification comes from measurement theory and scientific practice. The standard (empiricist) theory of measurement is metaphysically neutral. But its representational operational and axiomatic aspects give rise to several kinds of a one-sided metaphysics. In scientific practice. the scales of physical quantities (e.g. the mass or length scale) are indeed constructed from measuring methods which have incompatible axiomatic foundations. They cover concepts which belong to incomensurable theories. (...) I argue, however, that the construction of such scales conmmits us to a modest version of scientific realism. (shrink)
When philosophers of science relate Kant‘s theory of nature to modern physics, they neglect the critical parts of the Critique of Pure Reason. My paper focuses on the way in which Kant wanted to demonstrate the limitations of physical knowledge by means of the cosmological antinomy. According to Kant, cosmology gives rise to four variations of one-and-the-same antinomy of pure reason. He wanted to show that any attempt to complete our spatio-temporal or dynamical knowledge of the world is based on (...) a self-contradictory world view. Obviously he criticized the cosmological debates of his day whose topics are obsolete in our days. However, his doctrine of the antinomy of pure reason has a rationale which concerns the foundations of physics in Kant’s day as well as in ours. After giving a sketch of the subjects and of the structure of Kant’s antinomy, I present four variations on the theme "experience and completeness in physical theory" from a modern point of view. The fourth variation will indeed yield a conflict between the claims of completeness and the finite conditions of possible experience within physics which captures the rationale of Kant’s antinomy. Finally, I try to point out briefly how this rationale relates to Kant’s distinction of phenomena and noumena, and how this distinction can be re-interpreted in the context of modern physics. Indeed Niels Bohr made a similar distinction when he developed the Copenhagen interpretation of quantum mechanics. (shrink)
Adam Smith's metaphor of the "invisible hand" and its analogue in classical physics are investigated in detail. Smith's analogue was the mechanics of the solar system. What makes the analogy fail are not the idealisations in the caricature-like model of the rational economic man . The main problem rather is that the metaphor does not employ the correct analogue, which belongs to thermodynamics and statistics. In the simplest macro-economic model, the business cycle has the same formal structure as the heat (...) flow between two heat reservoirs and a business cycle of growing efficiency works like a refrigerator: it pumps money from the poor to the rich. More complicated models do not give a friendlier image. Due to technological push, an economic system behaves like a thermodynamic system far from the equilibrium, showing chaotic behaviour and developing into unpredictable states. (shrink)
Does incommensurability threaten the realist’s claim that physical magnitudes express properties of natural kinds? Some clarification comes from measurement theory and scientific practice. The standard theory of measurement is metaphysically neutral. But its representational operational and axiomatic aspects give rise to several kinds of a one-sided metaphysics. In scientific practice. the scales of physical quantities are indeed constructed from measuring methods which have incompatible axiomatic foundations. They cover concepts which belong to incomensurable theories. I argue, however, that the construction of (...) such scales conmmits us to a modest version of scientific realism. (shrink)
Was ist Natur oder was könnte sie sein? Diese und weitere Fragen sind grundlegend für Naturdenken und -handeln. Das Lehr- und Studienbuch bietet eine historisch-systematische und zugleich praxisbezogene Einführung in die Naturphilosophie mit ihren wichtigsten Begriffen. Es nimmt den pluralen Charakter der Wahrnehmung von Natur in den philosophischen Blick und ist auch zum Selbststudium bestens geeignet.