Entanglement, the quantum formalism and the classical world

TL;DR

This paper explores how entanglement, a key quantum feature, relates to classical correlations as Planck's constant approaches zero, suggesting a deep connection between quantum and classical mechanics.

Contribution

It demonstrates that entanglement in quantum systems can be mirrored by classical correlations in the semiclassical limit, providing new insights into the quantum-classical transition.

Findings

Entanglement generation is reproduced by classical correlations in the semiclassical limit.

Quantum and classical correlations become indistinguishable as Planck's constant vanishes.

Results shed light on the nature of quantum entanglement in relation to classical physics.

Abstract

75 years after the term "entanglement" was coined to a peculiar feature inherent to quantum systems, the connection between quantum and classical mechanics remains an open problem. Drawing on recent results obtained in semiclassical systems, we discuss here the fate of entanglement in a closed system as Planck's constant becomes vanishingly small. In that case the generation of entanglement in a quantum system is perfectly reproduced by properly defined correlations of the corresponding classical system. We speculate on what these results could imply regarding the status of entanglement and of the ensuing quantum correlations.