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Added by: Laura Jimenez
Abstract: Spin is typically thought to be a fundamental property of the electron and other elementary particles. Although it is defined as an internal angular momentum much of our understanding of it is bound up with the mathematics of group theory. This paper traces the development of the concept of spin paying particular attention to the way that quantum mechanics has influenced its interpretation in both theoretical and experimental contexts. The received view is that electron spin was discovered experimentally by Stern and Gerlach in 1921, 5 years prior to its theoretical formulation by Goudsmit and Uhlenbeck. However, neither Goudsmit nor Uhlenbeck, nor any others involved in the debate about spin cited the Stern-Gerlach experiment as corroborating evidence. In fact, Bohr and Pauli were emphatic that the spin of a single electron could not be measured in classical experiments. In recent years experiments designed to refute the Bohr-Pauli thesis and measure electron spin have been carried out. However, a number of ambiguities surround these results - ambiguities that relate not only to the measurements themselves but to the interpretation of the experiments. After discussing these various issues the author raises some philosophical questions about the ontological and epistemic status of spin.Allori, Valia. On the metaphysics of quantum mechanics2013, In Soazig Lebihan (ed.), Precis de la Philosophie de la Physique, Vuibert.-
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Abstract: Many solutions have been proposed for solving the problem of macroscopic superpositions of wave function ontology. A possible solution is to assume that, while the wave function provides the complete description of the system, its temporal evolution is not given by the Schroedinger equation. The usual Schroedinger evolution is interrupted by random and sudden "collapses". The most promising theory of this kind is the GRW theory, named after the scientists that developed it: Gian Carlo Ghirardi, Alberto Rimini and Tullio Weber. It seems tempting to think that in GRW we can take the wave function ontologically seriously and avoid the problem of macroscopic superpositions just allowing for quantum jumps. In this paper it is argued that such "bare" wave function ontology is not possible, neither for GRW nor for any other quantum theory: quantum mechanics cannot be about the wave function simpliciter. All quantum theories should be regarded as theories in which physical objects are constituted by a primitive ontology. The primitive ontology is mathematically represented in the theory by a mathematical entity in three-dimensional space, or space-time.Comment: This is a very interesting article on the ontology of Quantum Mechanics. It is recommended for advanced courses in Philosophy of Science, especially for modules in the Philosophy of physics. Previous knowledge of Bohmian mechanics and the Many Words Interpretation is necessary. Recommended for postgraduate students.
McGowan, M.K. The Metaphysics of Squaring Scientific Realism with Referential Indeterminacy1999, Erkenntnis 50(1): 87-94.-
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Added by: Laura Jimenez
Introduction: Scientific realism and the claim that there is radical referential indeterminacy are important and compelling philosophical theses. Each thesis has advocates and for good reason. On cursory examination, however, it seems that these theses are at odds with one another. It seems that one cannot both claim that science seeks to describe an objective reality and yet deny that reality is objectively structured in such a way as to determine the referents of our terms. Since there are compelling reasons in favour of each thesis and since it appears that some philosophers actually advocate both theses (Quine himself may be one such example), finding a way to square the theses would be multiply advantageous. On this paper, the author argues that despite the prima facie tension between them, these theses are indeed cotenable.Comment: Interesting paper that lies on the intersection between philosophy of science and philosophy of language. It could be used as a secondary reading for postgraduate courses in philosophy of science, in particular for lectures on the topic of scientific realism. The level of difficulty is not high, but it is more recommendable for students who have been introduced before to concepts such as realism, subjective supervientism and referential indeterminacy.
Drewery, Alice. Essentialism and the Necessity of the Laws of Nature2005, Synthese 144(3): 381-396.-
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Abstract: In this paper the author discusses and evaluates different arguments for the view that the laws of nature are metaphysically necessary. She conclude that essentialist arguments from the nature of natural kinds fail to establish that essences are ontologically more basic than laws, and fail to offer an a priori argument for the necessity of all causal laws. Similar considerations carry across to the argument from the dispositionalist view of properties, which may end up placing unreasonable constraints on property identity across possible worlds. None of her arguments preclude the possibility that the laws may turn out to be metaphysically necessary after all, but she argues that this can only be established by a posteriori scientific investigation. She argues for what may seem to be a surprising conclusion: that a fundamental metaphysical question - the modal status of laws of nature - depends on empirical facts rather than purely on a priori reasoning.Comment: An excellent paper that could serve as further or specialized reading for postgraduate courses in philosophy of science, in particular, for modules related to the study of the laws of nature. The paper offers an in-depth discussion of essentialist arguments, but also touches upon many other fundamental concepts such as grounding, natural kinds, dispositions and necessity.
Ismael, Jenann. Quantum Mechanics2014, The Standford Encyclopedia of Philosophy-
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Added by: Laura Jimenez
Introduction: Quantum mechanics is, at least at first glance and at least in part, a mathematical machine for predicting the behaviors of microscopic particles - or, at least, of the measuring instruments we use to explore those behaviors - and in that capacity, it is spectacularly successful: in terms of power and precision, head and shoulders above any theory we have ever had. Mathematically, the theory is well understood; we know what its parts are, how they are put together, and why, in the mechanical sense (i.e., in a sense that can be answered by describing the internal grinding of gear against gear), the whole thing performs the way it does, how the information that gets fed in at one end is converted into what comes out the other. The question of what kind of a world it describes, however, is controversial; there is very little agreement, among physicists and among philosophers, about what the world is like according to quantum mechanics. Minimally interpreted, the theory describes a set of facts about the way the microscopic world impinges on the macroscopic one, how it affects our measuring instruments, described in everyday language or the language of classical mechanics. Disagreement centers on the question of what a microscopic world, which affects our apparatuses in the prescribed manner, is, or even could be, like intrinsically; or how those apparatuses could themselves be built out of microscopic parts of the sort the theory describes.Comment: The paper does not deal with the problem of the interpretation of quantum mechanics, but with the mathematical heart of the theory; the theory in its capacity as a mathematical machine. It is recommendable to read this paper before starting to read anything about the interpretations of the theory. The explanation is very clear and introductory and could serve as an introductory reading for both undergraduate and postgraduate courses in philosophy of science focused on the topic of quantum mechanics. Though clearly written, there is enough mathematics here to potentially put off symbol-phobes.
Brading, Katherine, Elena Castellani. Symmetry and Symmetry Breaking2013, The Standford Encyclopedia of Philosophy-
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Added by: Laura Jimenez
Introduction: Symmetry considerations dominate modern fundamental physics, both in quantum theory and in relativity. Philosophers are now beginning to devote increasing attention to such issues as the significance of gauge symmetry, quantum particle identity in the light of permutation symmetry, how to make sense of parity violation, the role of symmetry breaking, the empirical status of symmetry principles, and so forth. These issues relate directly to traditional problems in the philosophy of science, including the status of the laws of nature, the relationships between mathematics, physical theory, and the world, and the extent to which mathematics suggests new physics. This entry begins with a brief description of the historical roots and emergence of the concept of symmetry that is at work in modern science. It then turns to the application of this concept to physics, distinguishing between two different uses of symmetry: symmetry principles versus symmetry arguments. It mentions the different varieties of physical symmetries, outlining the ways in which they were introduced into physics. Then, stepping back from the details of the various symmetries, it makes some remarks of a general nature concerning the status and significance of symmetries in physics.Comment: This article offers a good introduction to the topic of symmetries. The entry begins with a brief description of the historical roots and emergence of the concept of symmetry that could serve as a reading for undergraduates. It then turns to the application of this concept to physics and merges the discussion with issues in relativity and quantum mechanics. This second part of the article is thus more suitable to postgraduate courses in philosophy of science, specially, philosophy of physics. It could serve as a secondary reading for those researching the laws of nature.
Demarest, Heather. Fundamental Properties and the Laws of Nature2015, Philosophy Compass 10(5) 224-344.-
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Added by: Laura Jimenez
Abstract: Fundamental properties and the laws of nature go hand in hand: mass and gravitation, charge and electromagnetism, spin and quantum mechanics. So, it is unsurprising that one's account of fundamental properties affects one's view of the laws of nature and vice versa. In this essay,the author surveys a variety of recent attempts to provide a joint account of the fundamental properties and the laws of nature. Many of these accounts are new and unexplored. Some of them posit surprising entities, such as counterfacts. Other accounts posit surprising laws of nature, such as instantaneous laws that constrain the initial configuration of particles. These exciting developments challenge our assumptions about our basic ontology and provide fertile ground for further exploration.Comment: The article introduces in a simple way some fundamental concepts such as ‘law of nature’, ‘properties’, the notion of ‘categorical’ and ‘dispositional’ or the distinction between the governing and the systems approaches. It could serve as an introduction for those undergraduates that have never heard of these concepts before, or as a further reading for those in need of clarification. Some examples of modern fundamental physics are used as examples.
Nersessian, Nancy. Creating Scientific Concepts2008, MIT Press.-
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Added by: Laura Jimenez
Publisher's Note: How do novel scientific concepts arise? In Creating Scientific Concepts, Nancy Nersessian seeks to answer this central but virtually unasked question in the problem of conceptual change. She argues that the popular image of novel concepts and profound insight bursting forth in a blinding flash of inspiration is mistaken. Instead, novel concepts are shown to arise out of the interplay of three factors: an attempt to solve specific problems; the use of conceptual, analytical, and material resources provided by the cognitive-social-cultural context of the problem; and dynamic processes of reasoning that extend ordinary cognition. Focusing on the third factor, Nersessian draws on cognitive science research and historical accounts of scientific practices to show how scientific and ordinary cognition lie on a continuum, and how problem-solving practices in one illuminate practices in the other.Comment: Nersessian’s book has a two-fold foundation, first, the empirical analysis of two cases of scientific thinking (one from Maxwell and one from a verbal protocol of a scientist); second, philosophical and cognitive analysis of the overall picture of meaning change in science that is the result of her work. The book presents her argument via an introductory chapter, followed by five chapters that develop the argument. Chapter 4 is particularly interesting for the cognitive-scientist: in this chapter Nersessian develops her account of the basic cognitive processes that underlie model-based reasoning. The new approach to mental modeling and analogy, together with Nersessian’s cognitive-historical approach, make Creating Scientific Concepts equally valuable to cognitive science and philosophy of science. The book is accessible and well-written, and should be a relatively quick read for anyone with a previous background in the mentioned fields. It is mainly recommended for postgraduate courses.
Bokulich, Alisa. Distinguishing Explanatory from Nonexplanatory Fictions2012, Philosophy of Science 79(5): 725-737.-
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Added by: Jamie Collin
Abstract: There is a growing recognition that fictions have a number of legitimate functions in science, even when it comes to scientific explanation. However, the question then arises, what distinguishes an explanatory fiction from a nonexplanatory one? Here I examine two cases - one in which there is a consensus in the scientific community that the fiction is explanatory and another in which the fiction is not explanatory. I shall show how my account of "model explanations" is able to explain this asymmetry, and argue that realism - of a more subtle form - does have a role in distinguishing explanatory from nonexplanatory fictions.Comment: This would be useful in a course on the philosophy of science or the philosophy of fiction. It is particularly useful for teaching, as it is cutting edge in the philosophy of science but not particularly technical.
Massimi, Michela, Duncan Pritchard. What is this thing called science?2014, in M. Massimi (ed.), Philosophy and the Sciences for Everyone. Routledge-
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Added by: Laura Jimenez
Summary: This chapter offers a general introduction to philosophy of science. The first part of the chapter takes the reader through the famous relativist debate about Galileo and Cardinal Bellarmine. Several important questions on the topic are explored, such as what makes scientific knowledge special compared with other kinds of knowledge or the importance of demarcating science from non-science. Finally, the chapters gives an overview on how philosophers such as Popper, Duhem, Quine and Kuhn came to answer these questions.Comment: This chapter could be used as in introductory reading to review the nature of scientific knowledge and the most important debates about the scientific method. It is recommendable for undergraduate courses in philosophy of science. No previous knowledge of the field is needed in order to understand the content. The chapter is an introduction to the rest of the book Philosophy and the Sciences for Everyone. Some discussions explored here, such as the problem of underdetermination or Tomas Kuhn's view of scientific knowledge are central to the following chapters in philosophy of cosmology.
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Morrison, Margaret. Spin: All is not what it seems
2007, Studies in History and Philosophy of Science Part B 38(3): 529-55.
Comment: The goal of the paper is to uncover and isolate how spin presents problems for traditional realism and to illustrate the power that theories like quantum mechanics have for shaping both philosophical questions and answers. It is adequate for higher-level postgraduate courses in Philosophy of Science.