Nadia Blackshaw

The Many Minds Interpretations (MMI) of quantum mechanics received much attention in the late 1980s and 1990s. Since then, there has been very little focus on these approaches due to apparent problems that the similar Many Worlds Interpretation (MWI) does not face. In particular, a concern over the role of the mind in the MMI and the possibility of dualism entering the picture. This paper argues that it is incorrect to ignore the MMI purely due to concerns about dualism. There are always arguments for a dualistic worldview and it is important that solutions to the measurement problem do not rule out wider philosophical views. This paper re-examines key versions of the MMI and proposes one as an alternative picture to the MWI, where dualism might also be more palatable. The aim here is not to argue that a MMI is preferable to a MWI (putting aside any rival approaches as well), but rather that it is a valid option and thus should receive some more attention. Further, since the concern is often focused on the problem of dualism, a small defence is presented, showcasing dualistic theories that could be compatible with a quantum interpretation.

Everettian Quantum Mechanics (EQM) has been argued to face an epistemic problem due to its prediction that all physically possible outcomes occur on branches. This problem related to confirmation is seen to undermine the interpretations status as a scientific theory, since it seemingly cannot be disproven. This paper re-examines the epistemic problem and presents two aspects that make up this overall issue. By defining a relational and predictive problem, the aim is to identify how big of a problem this is for EQM. The relational problem, a weaker issue relating to accommodation of evidence, is argued to be solved by EQM. Therefore, Everettians themselves can understand existing quantum evidence as explainable within the EQM framework. However, it is argued that EQM cannot solve the predictive problem, focused on novel predictions over explanatory power. The interpretation lacks a coherent framework from which to understand evidence and its novel factor of the multiverse of branches, is not testable.

This paper shows that machine learning (ML) retrosynthesis models such as 3N-MCTS and AiZynthFinder incorporate non-epistemic values following the traditional inductive risk problem in philosophy of science. We argue that inductive risk in these cases is distributed, since it arises from the choice of model to construction, the data templates and to implementation. We connect this to traditional inductive risk but due to its proliferation throughout the process, call it distributed inductive risk. Second, we identify a novel source of inductive risk generated by algorithmic vagueness. Non-deterministic ML models cannot interpret vague terms and therefore must define notions like ‘chemical similarity’ into precise, operational categories. This involves moving beyond purely technical adaptations and ultimately points to a gap that is filled by appealing to value judgements. Unlike traditional inductive risk, which operates through explicit trade-offs between error types, algorithmic vagueness produces mandatory value commitments at the structural level.

This chapter investigates the formation and propagation of wave function “branches” through the process of entanglement with the environment. While this process is particularly important to some recent articulations of the Everett or “many-worlds” interpretation, it is a consequence of unitary dynamics, and hence significant to many if not all approaches to quantum theory. In this chapter we thus take a largely neutral stance on interpretation to investigate the shared consequences of unitary evolution. A highly idealized model of a locally interacting system and environment is described and investigated in several situations in which branching occurs, including those involving Bell inequality violating correlations; we illustrate how any nonlocality is compatible with the locality of the dynamics. Although branching is particularly important for many-worlds quantum theory, we take a neutral stance here, simply tracing out the consequences of a unitary dynamics. The overall goals are to provide a simple, concrete realization of the quantum physics of branch formation, and especially to emphasize the compatibility of branching with relativity; the chapter is intended to illuminate matters both for foundational work and for the application of quantum theory to non-isolated systems.