Peer-reviewed Journals

Laplace wondered about the minimal choice of initial variables and parameters corresponding to a well-posed initial value problem. Discussions of Laplace’s problem in the literature have focused on choosing between spatiotemporal variables relative to absolute space (i.e. substantivalism) or merely relative to other material bodies (i.e. relationalism) and between absolute masses (i.e. absolutism) or merely mass ratios (i.e. comparativism). This paper extends these discussions of Laplace’s problem, in the context of Newtonian Gravity, by asking whether mass needs to be included in the initial state at all, or whether a purely spatiotemporal initial state suffices. It is argued that mass indeed needs to be included; removing mass from the initial state drastically reduces the predictive and explanatory power of Newtonian Gravity.

  • Martens, N.C.M. (2017), “Regularity Comparativism about Mass in Newtonian Gravity”, Philosophy of Science 84(5): 1226-1238 [ Postprint | Published Version ]

Comparativism—the view that mass ratios are not grounded in absolute masses—faces a challenge by Baker which suggests that absolute masses are empirically meaningful. Regularity comparativism uses a liberalised version of the Mill-Ramsey-Lewis Best Systems Account to have both the Laws of Newtonian Gravity and the absolute mass scale supervene on a comparativist Humean mosaic as a package deal. I discuss three objections to this view, and conclude that it is untenable. The most severe problem is that once we have reduced away the absolute masses, there is nothing that stops us from also reducing the mass ratios.

Conference proceedings

Work in progress

  • Dark Matter = Modified Gravity? Scrutinising the spacetime-matter distinction via the modified gravity/ dark matter lens, with Dennis Lehmkuhl
  • The (Un)detectability of Absolute Newtonian Masses, draft available upon request
  • Machian Comparativism about Mass, draft available upon request
  • The Aharonov-Bohm Effect as a Case Study for Motivational Realism
  • The Metaphysics of Emergent Spacetime Theories, draft available upon request
  • Symmetry-to-reality inferences & sophistication, with James Read and Tom Møller-Nielsen