Are models our tools not our masters?

It is often claimed that one can avoid the kind of underdetermination that is a typical consequence of symmetries in physics by stipulating that symmetry-related models represent the same state of affairs (Leibniz Equivalence). But recent commentators (Dasgupta in Philos Perspect 25:115-160, 2011; Pooley in: Knox and Wilson (eds) The Routledge companion to the philosophy of physics, Routledge, Milton Park, 2021; Pooley and Read in Br J Philos Sci, 2021, https://doi.org/10.1086/718274; Teitel in J Philos 119:233-278, 2021) have responded that claims about the representational capacities of models are irrelevant to the issue of underdetermination, which concerns possible worlds themselves. In this paper I distinguish two versions of this objection: (1) that a theory's formalism does not (fully) determine the space of physical possibilities, and (2) that the relevant notion of possibility is not physical possibility. I offer a refutation of each.

Automated summary

This paper examines a counter-argument to the issue of underdetermination in physics, which claims that the representational capacities of models are irrelevant and the issue concerns possible worlds themselves. The paper refutes two versions of this objection, one regarding the formalism of a theory and the other concerning the notion of possibility.