Where Photons Have Been: nowhere without all of their wavefunctions

There has recently been renewed discussion of an experiment involving nested interferometers (presented by Danan et al, 2013). This experiment has been used by those authors (and others) to argue for the correctnesss of a formulation of quantum theory known as the “Two State Vector Formalism: (TSVF). In this paper, I take a close look at the experiment and note that the arguments used to support TSVF are based on neglecting crucial components of the wavefunction, and that if those components really were not involved in the physics, the experiment would not have provided the data. As this is a draft, comments are welcome.