Experimental Approaches to Distinguishing Quantum Collapse from Unitary Evolution: A Weak Measurement Perspective

TL;DR

This paper proposes an experiment using weak measurements to distinguish between quantum wave function collapse and purely unitary evolution, by analyzing the states of an 'unconscious observer' to infer measurement outcomes.

Contribution

It introduces a novel experimental framework employing weak measurements to differentiate between collapse and unitary interpretations of quantum mechanics.

Findings

Interference patterns indicate whether collapse has occurred.

The experiment can distinguish between collapse-based and unitary interpretations.

The approach provides a new method to test fundamental quantum mechanics interpretations.

Abstract

This paper proposes an experiment designed to distinguish between competing interpretations of quantum mechanics: those that involve wave function collapse and those that assume purely unitary evolution. The experiment tests whether an observer can measure a system without collapsing its wave function. To this end, we introduce the concept of an unconscious observer, defined by two criteria: (1) It measures a quantum system and sets the state of another system based on the result. (2) It allows an external experimentalist to infer the measurement outcome by examining the observer's state. The more distinguishable the observer's resulting states, the more it resembles a conventional measurement apparatus. Using weak measurements, the experimentalist probes these states, thereby testing the second criterion. The interference patterns observed in this setup reveal whether collapse has occurred, allowing experimental discrimination between collapse-based and unitary interpretations.