Quantum theory provides a framework for modern theoretical physics that enjoys enormous predictive and explanatory success. Yet, in view of the so-called “measurement problem”, there is no consensus on how physical reality can possibly be such that this framework has this success. The theory is thus an extremely well-functioning algorithm to predict and explain the results of observations, but no consensus on which kind of objective reality might plausibly underlie these observations.
Amongst the many attempts to provide an “interpretation” of quantum theory to account for this predictive and explanatory success, one class of interpretations hypothesizes backward-in-time causal influences—retrocausality—as the basis for constructing a convincing foundational account of quantum theory. This entry presents an overview of retrocausal approaches to the interpretation of quantum theory, the main motivations for adopting this approach, a selection of concrete suggested retrocausal models, and a review of the objections brought forward against such approaches.