Abstract

Bohmian mechanics faces an underdetermination problem: when it comes to solving the measurement problem, alternatives to the Bohmian guidance equa- tion work just as well as the official guidance equation. Dürr, Goldstein, and Zanghì have argued that of the candidate guidance equations, the official guid- ance equation is the simplest Galilean-invariant candidate. This symmetry argument—if it worked—would solve the underdetermination problem. But the argument does not work. It fails because it rests on assumptions about how Galilean transformations act on the wavefunction that are unwarranted. My discussion has larger morals about the phys- ical significance of certain mathematical results in non-orthodox interpretations of quantum mechanics.