Squeezing Inequalities and Entanglement for Identical Particles

TL;DR

This paper demonstrates that in systems of identical Bosonic qubits, certain non-local effects can violate squeezing inequalities without entanglement, impacting quantum measurement precision.

Contribution

It reveals that entanglement is not required to violate squeezing inequalities in identical particle systems, challenging previous assumptions.

Findings

Violations of squeezing inequalities occur without entanglement in Bosonic qubits.

Spin squeezing may not be necessary for sub-shot noise in atom interferometry.

Non-local effects are identified through correlations of commuting observables.

Abstract

By identifying non-local effects in systems of identical Bosonic qubits through correlations of their commuting observables, we show that entanglement is not necessary to violate certain squeezing inequalities that hold for distinguishable qubits and that spin squeezing may not be necessary to achieve sub-shot noise accuracies in ultra-cold atom interferometry.