PBR, nonreality and entangled measurement

TL;DR

This paper defends the PBR theorem against claims that entangled measurements are non-existent in the ensemble interpretation of quantum mechanics, arguing that the theorem remains valid.

Contribution

It critically analyzes Cabbolet's argument, reaffirming the validity of the PBR theorem and clarifying misconceptions about entangled measurements.

Findings

The PBR theorem remains valid against the nonexistence claim.

Cabbolet's argument does not provide sufficient reason to abandon entangled measurements.

The incompatibility between entangled measurements and $\\psi$-epistemic models is reaffirmed.

Abstract

In a recent paper, Cabbolet argues that the PBR theorem is nonreal since in the ensemble interpretation of quantum mechanics the entangled measurement used in the derivation of the PBR theorem is nonexisting. However, Cabbolet (1) doesn't provide any argument for the nonexistence of entangled measurements beyond the incompatibility of the existence of entangled measurements and the existence of $\psi$-epistemic models which we already know from the PBR theorem; and (2) he doesn't show why it is more reasonable to abandon entangled measurements instead of $\psi$-epistemic models. Hence, the PBR theorem remains intact.