Predictions and Primitive Ontology in Quantum Foundations: A Study of Examples

TL;DR

This paper examines the importance of primitive ontology in quantum theories by analyzing examples and toy models to understand how it influences the derivation of predictions and the theory's intelligibility.

Contribution

It demonstrates the value of primitive ontology in quantum foundations through detailed analysis of examples and toy models, clarifying its role in prediction derivation.

Findings

Primitive ontology clarifies the derivation of predictions.

Invalid prediction derivations often neglect primitive ontology.

Toy models illustrate the importance of primitive ontology in quantum theories.

Abstract

A major disagreement between different views about the foundations of quantum mechanics concerns whether for a theory to be intelligible as a fundamental physical theory it must involve a "primitive ontology" (PO), i.e., variables describing the distribution of matter in 4-dimensional space-time. In this paper, we illustrate the value of having a PO. We do so by focussing on the role that the PO plays for extracting predictions from a given theory and discuss valid and invalid derivations of predictions. To this end, we investigate a number of examples based on toy models built from the elements of familiar interpretations of quantum theory.