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111From Geometry to Conceptual RelativityErkenntnis 82 (5): 1043-1063. 2017.The purported fact that geometric theories formulated in terms of points and geometric theories formulated in terms of lines are “equally correct” is often invoked in arguments for conceptual relativity, in particular by Putnam and Goodman. We discuss a few notions of equivalence between first-order theories, and we then demonstrate a precise sense in which this purported fact is true. We argue, however, that this fact does not undermine metaphysical realism.
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376How is spontaneous symmetry breaking possible? Understanding Wigner's theorem in light of unitary inequivalenceStudies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 44 (4): 464-469. 2013.We pose and resolve a puzzle about spontaneous symmetry breaking in the quantum theory of infinite systems. For a symmetry to be spontaneously broken, it must not be implementable by a unitary operator in a ground state's GNS representation. But Wigner's theorem guarantees that any symmetry's action on states is given by a unitary operator. How can this unitary operator fail to implement the symmetry in the GNS representation? We show how it is possible for a unitary operator of this sort to con…Read more
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705To be a realist about quantum theoryIn Olimpia Lombardi (ed.), Quantum Worlds: Perspectives on the Ontology of Quantum Mechanics, . 2019.I look at the distinction between between realist and antirealist views of the quantum state. I argue that this binary classification should be reconceived as a continuum of different views about which properties of the quantum state are representationally significant. What's more, the extreme cases -- all or none --- are simply absurd, and should be rejected by all parties. In other words, no sane person should advocate extreme realism or antirealism about the quantum state. And if we focus on …Read more
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360A Theological Critique of the Fine-Tuning ArgumentIn Matthew A. Benton, John Hawthorne & Dani Rabinowitz (eds.), Knowledge, Belief, and God: New Insights in Religious Epistemology, Oxford University Press. pp. 122-135. 2018.According to the premises of the fine-tuning argument, most nomologically possible universes lack intelligent life; and the fact that ours has intelligent life is best explained by supposing it was created. However, if our universe was created, then the creator chose the laws of nature, and hence chose in favor of lifeless universes. In other words, the fine-tuning argument shows that God prefers universes without intelligent life; and the fact that our universe has intelligent life provides n…Read more
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217Algebraic quantum field theoryIn J. Butterfield & J. Earman (eds.), Handbook of the philosophy of physics, Kluwer Academic Publishers. 2006.Algebraic quantum field theory provides a general, mathematically precise description of the structure of quantum field theories, and then draws out consequences of this structure by means of various mathematical tools -- the theory of operator algebras, category theory, etc.. Given the rigor and generality of AQFT, it is a particularly apt tool for studying the foundations of QFT. This paper is a survey of AQFT, with an orientation towards foundational topics. In addition to covering the basics…Read more
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334AntimatterBritish Journal for the Philosophy of Science 61 (1): 93-121. 2010.The nature of antimatter is examined in the context of algebraic quantum field theory. It is shown that the notion of antimatter is more general than that of antiparticles. Properly speaking, then, antimatter is not matter made up of antiparticles—rather, antiparticles are particles made up of antimatter. We go on to discuss whether the notion of antimatter is itself completely general in quantum field theory. Does the matter–antimatter distinction apply to all field theoretic systems? The answe…Read more
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216Reconsidering Bohr's reply to EPRIn T. Placek & J. Butterfield (eds.), Non-locality and Modality, Kluwer Academic Publishers. pp. 3--18. 2001.Although Bohr's reply to the EPR argument is supposed to be a watershed moment in the development of his philosophy of quantum theory, it is difficult to find a clear statement of the reply's philosophical point. Moreover, some have claimed that the point is simply that Bohr is a radical positivist. In this paper, we show that such claims are unfounded. In particular, we give a mathematically rigorous reconstruction of Bohr's reply to the _original_ EPR argument that clarifies its logical struct…Read more
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143Maximal beable subalgebras of quantum-mechanical observablesInternational Journal of Theoretical Physics 38 2441-2484. 1999.The centerpiece of Jeffrey Bub's book Interpreting the Quantum World is a theorem (Bub and Clifton 1996) which correlates each member of a large class of no-collapse interpretations with some 'privileged observable'. In particular, the Bub-Clifton theorem determines the unique maximal sublattice L(R,e) of propositions such that (a) elements of L(R,e) can be simultaneously determinate in state e, (b) L(R,e) contains the spectral projections of the privileged observable R, and (c) L(R,e) is picked…Read more
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250Entanglement and Open Systems in Algebraic Quantum Field TheoryStudies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 32 (1): 1-31. 2001.Entanglement has long been the subject of discussion by philosophers of quantum theory, and has recently come to play an essential role for physicists in their development of quantum information theory. In this paper we show how the formalism of algebraic quantum field theory (AQFT) provides a rigorous framework within which to analyse entanglement in the context of a fully relativistic formulation of quantum theory. What emerges from the analysis are new practical and theoretical limitations on…Read more
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399The Semantic View, If Plausible, Is SyntacticPhilosophy of Science 80 (3): 475-478. 2013.Halvorson argues that the semantic view of theories leads to absurdities. Glymour shows how to inoculate the semantic view against Halvorson's criticisms, namely by making it into a syntactic view of theories. I argue that this modified semantic-syntactic view cannot do the philosophical work that the original "language-free" semantic view was supposed to do
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182The Measure of All Things: Quantum Mechanics and the SoulIn Mark C. Baker & Stewart Goetz (eds.), The Soul Hypothesis: Investigations Into the Existence of the Soul, Continuum Press. pp. 138. 2011.
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57On quanta, mind, and matter: Hans Primas in ContextStudies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 33 (4): 744-747. 2002.
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274Complementarity of representations in quantum mechanicsStudies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 35 (1): 45-56. 2004.We show that Bohr's principle of complementarity between position and momentum descriptions can be formulated rigorously as a claim about the existence of representations of the canonical commutation relations. In particular, in any representation where the position operator has eigenstates, there is no momentum operator, and vice versa. Equivalently, if there are nonzero projections corresponding to sharp position values, all spectral projections of the momentum operator map onto the zero eleme…Read more
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303The Conventionality of ParastatisticsBritish Journal for the Philosophy of Science 66 (4): 929-976. 2015.Nature seems to be such that we can describe it accurately with quantum theories of bosons and fermions alone, without resort to parastatistics. This has been seen as a deep mystery: paraparticles make perfect physical sense, so why don’t we see them in nature? We consider one potential answer: every paraparticle theory is physically equivalent to some theory of bosons or fermions, making the absence of paraparticles in our theories a matter of convention rather than a mysterious empirical disco…Read more
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226Reeh-schlieder defeats Newton-Wigner: On alternative localization schemes in relativistic quantum field theoryPhilosophy of Science 68 (1): 111-133. 2001.Many of the "counterintuitive" features of relativistic quantum field theory have their formal root in the Reeh-Schlieder theorem, which in particular entails that local operations applied to the vacuum state can produce any state of the entire field. It is of great interest then that I.E. Segal and, more recently, G. Fleming (in a paper entitled "Reeh-Schlieder meets Newton-Wigner") have proposed an alternative "Newton-Wigner" localization scheme that avoids the Reeh-Schlieder theorem. In this …Read more
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297No place for particles in relativistic quantum theories?Philosophy of Science 69 (1): 1-28. 2002.David Malament (1996) has recently argued that there can be no relativistic quantum theory of (localizable) particles. We consider and rebut several objections that have been made against the soundness of Malament’s argument. We then consider some further objections that might be made against the generality of Malament’s conclusion, and we supply three no‐go theorems to counter these objections. Finally, we dispel potential worries about the counterintuitive nature of these results by showing th…Read more
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238A note on information theoretic characterizations of physical theoriesStudies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 35 (2): 277-293. 2003.Clifton, Bub, and Halvorson (CBH) have recently argued that quantum theory is characterized by its satisfaction of three fundamental information-theoretic constraints. However, it is not difficult to construct apparent counterexamples to the CBH characterization theorem. In this paper, we discuss the limits of the characterization theorem, and we provide some technical tools for checking whether a theory (specified in terms of the convex structure of its state space) falls within these limits.
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686What Scientific Theories Could Not BePhilosophy of Science 79 (2): 183-206. 2012.According to the semantic view of scientific theories, theories are classes of models. I show that this view -- if taken seriously as a formal explication -- leads to absurdities. In particular, this view equates theories that are truly distinct, and it distinguishes theories that are truly equivalent. Furthermore, the semantic view lacks the resources to explicate interesting theoretical relations, such as embeddability of one theory into another. The untenability of the semantic view -- as cur…Read more
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192Why methodological naturalism?In Kelly James Clark (ed.), Blackwell Companion to Naturalism, Blackwell. 2016.I discuss motivations for methodological naturalism in science. I argue that methodological naturalism neither needs nor supports metaphysical naturalism.
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440On the nature of continuous physical quantities in classical and quantum mechanicsJournal of Philosophical Logic 30 (1): 27-50. 2001.Within the traditional Hilbert space formalism of quantum mechanics, it is not possible to describe a particle as possessing, simultaneously, a sharp position value and a sharp momentum value. Is it possible, though, to describe a particle as possessing just a sharp position value (or just a sharp momentum value)? Some, such as Teller, have thought that the answer to this question is No - that the status of individual continuous quantities is very different in quantum mechanics than in classical…Read more
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224Categories of scientific theoriesIn Elaine Landry (ed.), Categories for the Working Philosopher, Oxford University Press. 2018.We discuss ways in which category theory might be useful in philosophy of science, in particular for articulating the structure of scientific theories. We argue, moreover, that a categorical approach transcends the syntax-semantics dichotomy in 20th century analytic philosophy of science.
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284Characterizing quantum theory in terms of information-theoretic constraintsFoundations of Physics 33 (11): 1561-1591. 2002.We show that three fundamental information-theoretic constraints -- the impossibility of superluminal information transfer between two physical systems by performing measurements on one of them, the impossibility of broadcasting the information contained in an unknown physical state, and the impossibility of unconditionally secure bit commitment -- suffice to entail that the observables and state space of a physical theory are quantum-mechanical. We demonstrate the converse derivation in part, a…Read more
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248Scientific TheoriesIn Paul Humphreys (ed.), The Oxford Handbook of Philosophy of Science, Oxford University Press. pp. 585-608. 2014.Since the beginning of the 20th century, philosophers of science have asked, "what kind of thing is a scientific theory?" The logical positivists answered: a scientific theory is a mathematical theory, plus an empirical interpretation of that theory. Moreover, they assumed that a mathematical theory is specified by a set of axioms in a formal language. Later 20th century philosophers questioned this account, arguing instead that a scientific theory need not include a mathematical component; or t…Read more
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178On information-theoretic characterizations of physical theoriesStudies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 35 (2): 277-293. 2004.
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178A philosopher's understanding of quantum mechanics: Possibilities and impossibilities of a modal interpretation Pieter VermaasBritish Journal for the Philosophy of Science 52 (2): 387-391. 2001.
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248Jill North argues that Hamiltonian mechanics provides the most spare -- and hence most accurate -- account of the structure of a classical world. We point out some difficulties for her argument, and raise some general points about attempts to minimize structural commitments
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22Review of Pieter E. Vermaas: A philosopher's understanding of quantum mechanics: possibilities and impossibilities of a modal interpretation (review)British Journal for the Philosophy of Science 52 (2): 387-391. 2001.
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920Plantinga on Providence and PhysicsEuropean Journal for Philosophy of Religion 5 (3): 19--30. 2013.Discussion of Alvin Plantinga's book, "Where the Conflict Really Lies"
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208Locality, localization, and the particle concept: Topics in the foundations of quantum field theoryDissertation, University of Pittsburgh. 2001.This dissertation reconsiders some traditional issues in the foundations of quantum mechanics in the context of relativistic quantum field theory (RQFT); and it considers some novel foundational issues that arise first in the context of RQFT. The first part of the dissertation considers quantum nonlocality in RQFT. Here I show that the generic state of RQFT displays Bell correlations relative to measurements performed in any pair of spacelike separated regions, no matter how distant. I also show…Read more
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300Are Rindler Quanta Real? Inequivalent Particle Concepts in Quantum Field TheoryBritish Journal for the Philosophy of Science 52 (3): 417-470. 2001.Philosophical reflection on quantum field theory has tended to focus on how it revises our conception of what a particle is. However, there has been relatively little discussion of the threat to the "reality" of particles posed by the possibility of inequivalent quantizations of a classical field theory, i.e., inequivalent representations of the algebra of observables of the field in terms of operators on a Hilbert space. The threat is that each representation embodies its own distinctive concep…Read more
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Princeton UniversityDepartment of Philosophy
Department of MathematicsStuart Professor of Philosophy -
Princeton, New Jersey, United States of America
Areas of Specialization
Philosophy of Physical Science |
Logic and Philosophy of Logic |
General Philosophy of Science |
PhilPapers Editorships
Philosophy of Physical Science |