Speaker: Tom Pashby (Pittsburgh) Wednesday 11th July 2013 Ludwigstr.31 Room E021 Time: 6 to 8 pm Title: Letting Things Happen: Quantum Mechanics as a Theory of Events Abstract: In this paper I argue for two controversial claims. The first is that Ordinary Quantum Mechanics, which represents observables by self-adjoint operators on a Hilbert space and propositions by projections, is inadequate for the description of many experimental setups involving non-instantaneous measurements. Ordinary QM thus fails to be empirically adequate. The second claim is that quantum mechanics, properly understood, is not a theory of wavefunctions and their dynamical evolution but of conditional probabilities for the occurrence of events at particular times. Moreover, I argue that the second claim follows from addressing the first. That is, I claim that in order to accommodate experiments of the type that Ordinary QM fails to describe one is led towards the view that quantum mechanics concerns the occurrence of physical events rather than the dynamical evolution of a material object. There are two steps in the progression. First, I advocate the use of so-called event time or time of occurrence observables, which do not correspond to self-adjoint operators. Second, to accommodate multi-case conditionalisation I advocate the use of the Extended Schroedinger Equation, which applies to functions of time and space rather than of space alone and so is not a dynamical equation for a spatial wavefunction.