The Bundle Theory Approach to Relational Quantum Mechanics

TL;DR

This paper offers a new metaphysical interpretation of Relational Quantum Mechanics using mereological bundle theory, emphasizing properties and observer-dependent variations to support a property-oriented and realist ontology.

Contribution

It introduces a novel metaphysical framework for RQM based on mereological bundle theory, aligning it with property-oriented ontology and moderate structural realism.

Findings

RQM can be interpreted as a fusion of observer-dependent properties

The framework supports a property-oriented ontology for physical objects

RQM can be classified as a full-fledged realist interpretation

Abstract

The present essay provides a new metaphysical interpretation of Relational Quantum Mechanics (RQM) in terms of mereological bundle theory. The essential idea is to claim that a physical system in RQM can be defined as a mereological fusion of properties whose values may vary for different observers. Abandoning the Aristotelian tradition centered on the notion of substance, I claim that RQM embraces an ontology of properties that finds its roots in the heritage of David Hume. To this regard, defining what kind of concrete physical objects populate the world according to RQM, I argue that this theoretical framework can be made compatible with (i) a property-oriented ontology, in which the notion of object can be easily defined, and (ii) moderate structural realism, a philosophical position where relations and relata are both fundamental. Finally, I conclude that under this reading relational quantum mechanics should be included among the full-fledged realist interpretations of quantum theory.