Quantum decoherence in a pragmatist view: Part I

TL;DR

This paper explores how quantum decoherence supports a pragmatist interpretation of quantum theory, emphasizing its role in understanding physical claims and guiding probability application without relying on measurement.

Contribution

It offers a pragmatist perspective on decoherence, clarifying its role in inference and probability use, contrasting with Bohr's approach, and demonstrating this in simple models and applications.

Findings

Decoherence licenses the use of Born's rule without measurement.

The content of quantum claims is understood through their inferential role.

Applications include laboratory and natural systems.

Abstract

The quantum theory of decoherence plays an important role in a pragmatist interpretation of quantum theory. It governs the descriptive content of claims about values of physical magnitudes and offers advice on when to use quantum probabilities as a guide to their truth. The content of a claim is to be understood in terms of its role in inferences. This promises a better treatment of meaning than that of Bohr. Quantum theory models physical systems with no mention of measurement: it is decoherence, not measurement, that licenses application of Born's probability rule. So quantum theory also offers advice on its own application. I show how this works in a simple model of decoherence, and then in applications to both laboratory experiments and natural systems. Applications to quantum field theory and the measurement problem will be discussed elsewhere.