According to Healey’s pragmatist quantum realism, the only physical properties of quantum systems are those to which the Born rule assigns probabilities. In this paper, I argue that this approach to quantum theory fails to explain the results of protective measurements.

Quantum theory is a fundamental part of contemporary science. But some recent arguments have been taken to show that if this theory is universally applicable then the outcome of a quantum measurement is not an objective fact. They motivate the more general reappraisal of the notions of fact and objectivity that I offer here. I argue that if quantum theory is universally applicable the facts about the physical world include a fact about each quantum measurement outcome. The physical facts may (...) lack an ideal kind of objectivity, but their more modest objectivity is all that science needs. (shrink)

Experiments involving delayed-choice entanglement swapping seem to suggest that particles can become entangled after they’ve already been detected. This astonishing result is taken by some to undermine realism about entanglement. In this paper, I argue that one can offer a fully realist explanation of delayed-choice entanglement swapping by countenancing timelike entanglement relations. I argue that such an explanation—radical though it may be—isn’t incoherent and doesn’t invite paradox. I compare this approach to the antirealist alternative and a more deflationary realist strategy (...) defended by Egg, each of which face certain challenges. The upshot is that we should take seriously the possibility of timelike entanglement and seek to develop a framework for quantum theory which allows for it. (shrink)

In this paper I present a new perspective for interpreting the wavefunction as a non-material, non-epistemic, non-representational entity. I endorse a functional view according to which the wavefunction is defined by its roles in the theory. I argue that this approach shares some similarities with the nomological account of the wave function as well as with the pragmatist and epistemic approaches to quantum theory, while avoiding the major objections of these alternatives.

A Controlled Not variant of the standard quantum teleportation protocol affords a step-by-step analysis of what is, or can be said to be, achieved in the process in either location. Dominant interpretations of what quantum teleportation consists in and implies are reviewed in this light. Being mindful of the statistical significance of the terms and operations involved, as well as awareness of classical analogies, can help sort out what is specifically quantum-mechanical, and what is not, in so-called teleportation. What the (...) latter achieves appears to be the transmission, without the involvement of mysterious channels, of what a quantum state encapsulates: the multitiered probabilistic characterization of a given preparation, which might be all we can possibly know about a physical system in a given experimental situation. (shrink)