On the derivation of wave function reduction from Schr\"odinger's equation: A model

TL;DR

This paper explores how wave function reduction can be derived from Schrödinger's equation using a statistical physics model, demonstrating consistency with quantum non-separability and classical emergence.

Contribution

It presents a novel derivation of wave function reduction from quantum mechanics through a specific model, bridging quantum principles with classical measurement outcomes.

Findings

Reduction can be derived from quantum mechanics using statistical physics methods.

The model is consistent with quantum non-separability and locality of measurements.

Quantitative estimates support the model's validity.

Abstract

The possibility of consistency between the basic quantum principles and reduction (wave function reduction) is reexamined. The mathematical description of an organized macroscopic device is constructed explicitly as a convenient tool for this investigation. A derivation of reduction from quantum mechanics is proposed on a specific example, using standard methods of statistical physics. Although these methods are valid only "for all practical purposes", arguments are given to ascribe an emerging status to reduction (or the uniqueness of physical reality), similar to the status of classical physics. Examination of measurements of the particles in an EPR pair by two space-like separated apparatuses shows that the model is consistent with the non-separable character of quantum mechanics, although both measurements are local. Quantitative estimates are given.