Passive quantum reference frame transformations cannot create entanglement between physical systems

TL;DR

This paper demonstrates that passive quantum reference frame transformations cannot generate entanglement between physical systems, providing a necessary condition for entanglement creation and clarifying the role of reference frames in quantum entanglement.

Contribution

It introduces the concept of passive quantum reference frames and proves that transformations between them cannot produce entanglement, advancing understanding of quantum reference frames.

Findings

Passive quantum reference frame transformations cannot create entanglement.

A necessary condition for entanglement generation after reference frame transformation.

Results apply to perspectival quantum frameworks without physical-reference distinction.

Abstract

We find a necessary condition for subsystems to become entangled after a quantum reference frame transformation. By distinguishing between quantum systems suitable to act as reference frames and physical systems described relative to these frames, we define passive quantum reference frames and show that transformations between these cannot produce entanglement between physical systems. Our results also apply to the study of entanglement between subsystems in the perspectival framework even when there is no distinction between physical and reference systems.