The received view on quantum non-individuality: formal and metaphysical analysis

Décio Krause

D�cio Krause, Steven French

Nathan Moore

One recent debate in philosophy of physics has centered whether quantum particles are individuals or not. The received view is that particles are not individuals and the standard methodology is to approach the question via the structure of quantum theory. I challenge both the received view and the standard methodology. I contend not only that the structure of quantum theory is not the right place to look for conditions of individuality that quantum particles may or may not satisfy, but also that there is an important role for traditional metaphysics to play. Consequently, my work brings together the philosophy of physics and traditional metaphysics literatures to shed new light on the debate over the individuality of quantum particles. I defend a set of conditions of individuality and argue that quantum particles satisfy these conditions thereby defending the view that particles are individuals in opposition to the received view. I also challenge a second feature of the standard methodology insofar as I challenge the significance of the Principle of the Identity of Indiscernibles in terms of which much discussion in the philosophy of physics literature is framed. My work is significant in a number of additional ways as well. My work implies that the dominant explanation for quantum statistics in terms of non-individuality is incorrect and it also undermines the ontic-structural realists metaphysical underdetermination challenge to the scientific realist.

Matteo Morganti

Raoni Wohnrath Arroyo, Jonas R. Becker Arenhart

This article critically examines the challenges of developing a metaphysics of non-individuals in the context of quantum mechanics. It investigates the Received View, which posits that quantum entities are non-individuals, and highlights several unresolved issues. Through these challenges, it is shown that a coherent metaphysics of non-individuals remains an ongoing project. Section 2 outlines the historical motivations behind a metaphysics of non-individuals in quantum mechanics, providing insight into how physics seems to necessitate such a framework. Section 3 discusses how these motivations have been articulated in the traditional approach (referred to here as the ‘non-reflexive proposal’), which characterizes non-individuality as a failure of the identity relation to apply. Section 4 situates the problem within a broader context, extracting methodological insights and clarifying the issue. Section 5 elaborates on the challenges that a metaphysics of non-individuals must still overcome, positioning this text as a prolegomenon to future formulations of such a metaphysics grounded in quantum mechanics, and section 6 wraps it all up.

Décio Krause