How Do Things Persist? Location Relations in Physics and the Metaphysics of Persistence

This paper investigates the use of theories of mechanics (classical and quantum) to provide answers to questions in the metaphysics of spatial location and persistence. Investigating spatial location, I find that in classical physics bodies pertend the region of space at which they are exactly located, while a quantum system spans a region at which it is exactly located. Following this analysis, I present a ‘no-go’ result which shows that quantum mechanics (conventionally interpreted) restricts the available options for locational persistence theories in an interesting way: it demonstrates that the spatiotemporal path of a persisting thing is discrete (or discontinuous) in time. This leads to unpalatable consequences for both perdurantists and endurantists. In particular, I argue that Butterfield’s ‘anti-pointilliste’ perdurantism is ruled out, and show that endurantists relying on immanent causation run into trouble. I conclude by suggesting the revival of Whitehead’s alternative mode of persistence called ‘reiteration.