 One way to understand the role that retrocausality plays in circumventing the results of the no-go theorems is to consider each theorem to be underpinned by what is known as the ontological models framework (Harrigan &amp; Spekkens 2010; Leifer 2014; Ringbauer 2017). The ontological models framework formalizes and captures the central notion of realism in quantum theory (and so subsumes local hidden variable approaches to quantum mechanics). The framework consists of an operational description of a general quantum process, which describes observed statistics for outcomes of measurements given both preparations and transformations, along with an ontological model (or “ontic extension”) accounting for the observed statistics. For every preparation procedure, which is usually said to result in a quantum state \(\psi\), the quantum system is in fact prepared in an “ontic” state \(\lambda\), chosen from a set of states \(\Lambda\), which completely specifies the system’s properties. The framework leaves open (and is ultimately used to define) whether the quantum state \(\psi\) is itself an ontic or epistemic state (if \(\psi\) is ontic, \(\lambda\) either includes additional ontic degrees of freedom, or is in one-to-one correspondence with \(\psi\); see  §3.3).  Each preparation is assumed to result in some \(\lambda\) via a classical probability density over \(\Lambda\), and a set of measurement procedures that determine conditional probabilities for outcomes dependent upon \(\lambda\) (which thus screens off the preparation procedure \(\psi\)); explicitly, \(\lambda\) does not causally depend on any future measurement setting \(\alpha\). Finally, the operational statistics must reproduce the quantum statistics.