Research

Published and Forthcoming

“Friedman and Some of his Critics on the Foundations of General Relativity.” In Einstein Studies, vol. 15, edited by T. Sauer, C. Beisbart, and C. Wüthrich. Birkhäuser: Boston, forthcoming 2019. (preprint)

Abstract: The paper is an examination of Michael Friedman’s analysis of the conceptual structure of Einstein’s theory of gravitation, with a particular focus on a number of critical reactions to it. Friedman argues that conceptual frameworks in physics are stratified, and that a satisfactory analysis of a framework requires us to recognize the differences in epistemological character of its components. He distinguishes first-level principles that define a framework of empirical investigation from second-level principles that are formulable in that framework. On his account, the theory of Riemannian manifolds and the equivalence principle define the framework of empirical investigation in which Einstein’s field equations are an intellectual and empirical possibility. Friedman is a major interpreter of relativity and his view has provoked a number of critical reactions, nearly all of which miss the mark. I aim to free Friedman’s analysis of Einsteinian gravitation from a baggage of misconceptions and to defend the notion that physical theories are stratified. But I, too, am a critic and I criticize Friedman’s view on several counts, notably his account of a constitutive principle and that of the principle of equivalence.

“Newtonian Mechanics and its Philosophical Significance.” In The Routledge Companion to the Philosophy of Physics, edited by E. Knox and A. Wilson. London: Routledge, forthcoming 2019. (preprint)

Abstract: Newtonian mechanics is more than just an empirically successful theory of matter in motion: it is an account of what knowledge of the physical world should look like. But what is this account? What is distinctive about it? To answer these questions, I begin by introducing the laws of motion, the relations among them, and the spatio-temporal framework that is implicit in them. Then I turn to the question of their methodological character. This has been the locus of philosophical discussion from Newton’s time to the present, and I survey the views of some of the major contributors. I show that while Newtonian mechanics motivates a number of philosophical ideas about force, mass, motion, and causality – and through this, ideas about space and time – the laws are themselves the outcome of a philosophical or critical conceptual analysis.

“The Principle of Equivalence as a Criterion of Identity,” Synthese (2018), doi:10.1007/s11229-018-01897-w. (journal) (preprint)

Abstract: In 1907 Einstein had the insight that bodies in free fall do not “feel” their own weight. This has been formalized in what is called “the principle of equivalence.” The principle motivated a critical analysis of the Newtonian and special-relativistic concepts of inertia, and it was indispensable to Einstein’s development of his theory of gravitation. A great deal has been written about the principle. Nearly all of this work has focused on the content of the principle and whether it has any content in Einsteinian gravitation, but more remains to be said about its methodological role in the development of the theory. I argue that the principle’s methodological significance resides in its motivation of a criterion of identity for the motions of freely falling frames and inertial frames. This work extends and substantiates a recent account of the notion of a criterion of identity by William Demopoulos. Demopoulos argues that the notion can be employed more widely than in the foundations of arithmetic and that we see this in the development of physical theories, in particular space-time theories. This new account forms the basis of a general framework for applying a number of mathematical theories and for distinguishing between applied mathematical theories that are and are not empirically constrained.

“There is No Conspiracy of Inertia,” British Journal for the Philosophy of Science 69, no. 4 (2018): 957-82. Published online May 18, 2017. (journal) (preprint)

Abstract: I examine two claims that arise in Harvey Brown’s account of inertial motion in Physical Relativity (2005). Brown claims there is something objectionable about the way in which the motions of free particles in Newtonian theory and special relativity are coordinated. Brown also claims that since a geodesic principle can be derived in Einsteinian gravitation the objectionable feature is explained away. I argue that there is nothing objectionable about inertia and that, while the theorems that motivate Brown’s second claim can be said to figure in a deductive-nomological explanation, their main contribution lies in their explication rather than their explanation of inertial motion.

“Friedman’s Thesis,” Studies in History and Philosophy of Modern Physics 52 (2015): 129-38. (journal) (preprint)

Abstract: This essay examines Michael Friedman’s recent approach to the analysis of physical theories. Friedman argues against Quine that the identification of certain principles as “constitutive” is essential to a satisfactory methodological analysis of physics. I explicate Friedman’s characterization of a constitutive principle, and I evaluate his account of the constitutive principles that Newtonian and Einsteinian gravitation presuppose for their formulation. I argue that something close to Friedman’s thesis is defensible.

“On Identifying Background-Structure in Classical Field Theories,” Philosophy of Science 78, no. 5 (2011): 1070-81. (journal) (revised and extended version (2013))

Abstract: I examine a property of theories called “background-independence” that Einsteinian gravitation is thought to exemplify. This concept has figured in the work of Rovelli (2001, 2004), Smolin (2006), Giulini (2007), and Belot (2011), among others. I propose and evaluate a few candidates for background-independence, and I show that there is something chimaerical about the concept. I argue, however, that there is a proposal that clarifies the feature of Einsteinian gravitation that motivates the concept.

 

Manuscripts in Preparation for Submission

“Corollary VI to the Laws of Motion: What it Does and Does Not Establish”

“Of What Interest is the Notion of a Criterion of Identity to the Foundations of Physics?”

“Some Remarks on ‘Einstein-Feigl Completeness’ and its Significance”

 

Thesis

Some Disputed Aspects of Inertia, with Particular Reference to the Equivalence Principle, PhD thesis (University of Western Ontario, 2013).