B. Ontologically Oriented Survey of Quantum Mechanics

William M. Simpson

ABSTRACT This article surveys recent work on primitive ontology (PO) approaches to quantum mechanics, focusing on proposals that seek to integrate this approach with the metaphysics of causal powers. PO approaches aim to provide a clear metaphysical picture in which the world consists of local entities such as particles, matter density fields or flashes, and these entities compose macroscopic objects, such as scientists and their measuring devices. To account for the behaviour of these local entities, some PO theories invoke the metaphysics of powers. After motivating PO approaches and contrasting them with wave function realism, I consider the development of power‐based POs, contrasting them with both Humean POs and POs which invoke primitive laws. I explain how different power‐based frameworks address key quantum phenomena, and I survey some difficulties, including the Problem of Holism, of small worlds and of top‐down causation. Such challenges are best confronted, I suggest, by drawing on Aristotelian hylomorphism: If powers are grounded in forms that unify physical systems, then power‐based POs can accommodate holistic and context‐sensitive behaviour.

Michael Epperson

Edward M. MacKinnon

This article probes the question of what interpretations of quantum mechanics actually accomplish. In other domains, which are briefly considered, interpretations serve to make alien systematizations intelligible to us. This often involves clarifying the status of their implicit ontology. A survey of interpretations of non-relativistic quantum mechanics supports the evaluation that these interpretations make a contribution to philosophy, but not to physics. Interpretations of quantum field theory are polarized by the divergence between the Lagrangian field theory that led to the Standard Model of Particle physics and the Algebraic quantum field theory, that discounts an ontology of particles. Ruetsche's interpretation, it is argued, offers a potential for loosening the sharp polarization that presently obtains. A brief evaluation focuses on the functional ontology of quantum field theory considered as an effective theory.

Shan Gao

Jorge Manero

Abstract It has been argued that in the context of Bohm’s approach to quantum mechanics, the postulation of a three-dimensional ontology (as opposed to a high-dimensional one) is presumed to be the only interpretation that may reliably support object-oriented realism by virtue of the fact that this ontology is approximately preserved through scientific change, at least in the classical–quantum transition. Based on an interpretative analysis of the Bohmian formulation, I shall critically evaluate the tenability of this argument. In so doing, I shall argue that this formulation admits the postulation of an alternative ontology that is properly defined in a high-dimensional space, and is approximately preserved among this transition. As a result, both the three-dimensional and the high-dimensional worldviews shall form the basis of an equally reliable endorsement of object-oriented realism in the context of the Bohmian framework. I shall conclude that this argument becomes a problem of metaphysical underdetermination between a three and a high-dimensional Bohmian interpretation.