What is the connection between quantum relationality and symmetry-based relationality?

Abstract

Although it has often been noted that both quantum mechanics and relativistic physics involve significant forms of relationality, the nature of the connection remains unclear. In addressing such a question it makes sense to start from the simplest possibility, so in this article I set out to consider the viability of the hypothesis that the two types of relationality are ultimately the same: that is, quantum states always characterize degrees of freedom which can be changed by a symmetry transformation, so they are relativized for exactly the same reason as partial observables in general relativity. I use the idea that we only measure partial observables to argue that this suggestion is compatible with all existing empirical evidence for quantum mechanics, and then I consider the consequences for ongoing debates about the nature of measurement in quantum mechanics.