Talk: Michael Dascal (Maryland)
For Hume, Bell tolls.
There has recently been a great deal of interest in neo-Bohrian, observer-dependent quantum theories, as seen, for example, in Frauchiger and Renner (2018), Bruckner (2018), and Baumann and Wolf (2018). A standard concern raised against such interpretations, perhaps discussed most recently by Salom (2018), is that any consideration of superobservers leads to inconsistency: If an observer A measures some system s, and a superobserver B (who treats A and s as evolving unitarily) measures A, the Born rule dictates that it is possible for B’s result to be inconsistent with what A observed. I explain here that this concern is unwarranted. Specifically, I argue that the worry stems from standard intuitions about causation and show that if we reject these intuitions in light of contemporary Humeanism then all that is needed to avoid inconsistency comes directly from the linearity of Schrödinger dynamics. Noting that one might see this appeal to Schrödinger dynamics as unwarranted (or the linearity of the dynamics as itself ad hoc), I conclude by offering some viable Humean and ‘quasi-Humean’ positions that might defend such a move.