Bohm’s Approach and Individuality

Abstract

Ladyman and Ross (LR) argue that quantum objects are not individuals (or are at most weakly discernible individuals) and use this idea to ground their metaphysical view, ontic structural realism, according to which relational structures are primary to things. LR acknowledge that there is a version of quantum theory, namely the Bohm theory (BT), according to which particles do have definite trajectories at all times. However, LR interpret the research by Brown et al. as implying that "raw stuff" or haecceities are needed for the individuality of particles of BT, and LR dismiss this as idle metaphysics. In this paper we note that Brown et al.'s research does not imply that haecceities are needed. Thus BT remains as a genuine option for those who seek to understand quantum particles as individuals. However, we go on to discuss some problems with BT which led Bohm and Hiley to modify it. This modified version underlines that, due to features such as contextdependence and non-locality, Bohmian particles have a very limited autonomy in situations where quantum effects are non-negligible. So while BT restores the possibility of quantum individuals, it also underlines the primacy of the whole over the autonomy of the parts. The later sections of the paper also examine the Bohm theory in the general mathematical context of symplectic geometry. This provides yet another way of understanding the subtle, holistic and dynamic nature of Bohmian individuals. We finally briefly consider Bohm's other main line of research, the 'mplicate order", which is in some ways similar to LR's structural realism.

Events and the Ontology of Quantum Mechanics

“…This reading goes against a "generosity" principle advocated by Brown et al (1996), Pylkkänen et al (2014), who plausibly attribute particles some degree of intrinsicality. If the wave function really "embodied" all apparently intrinsic properties of particles, and referred to a global power of the configuration of particles, how could such a global power be considered concrete and not just an abstract property of the configuration?…”

Bohm's quantum potential as an internal energy

“…This brings out one of the differences in the behaviour of a photon and a lepton (particle), a difference that forces us to treat the electromagnetic field in a different way [4]. Furthermore it illustrates that the concept of a particle in Bohm's theory is very different from that of a classical particle [20].…”

Individuality and the Account of Nonlocality: The Case for the Particle Ontology in Quantum Physics

“…Brown et al (1995Brown et al ( , 1996 and references therein; cf. most recently Pylkkänen et al (2015) and ).…”