Amplification of Gravitationally Induced Entanglement

TL;DR

This paper proposes a novel criterion using weak values and EPR steering to amplify and detect gravitationally induced entanglement, potentially revealing gravity's nonclassical nature despite weak signals.

Contribution

It introduces a method to amplify gravitationally induced entanglement signals using weak-value scenarios and EPR steering, overcoming previous detection limitations.

Findings

Amplification of gravitational entanglement signals is theoretically possible.

Classical mediators cannot simulate amplified weak-value phenomena in EPR steering.

The approach enhances the prospects for experimental detection of gravity's quantum features.

Abstract

Observation of gravitationally induced entanglement between two massive particles can be viewed as implying the existence of the nonclassical nature of gravity. However, weak interaction in the gravitational field is extremely small so that gravitationally induced entanglement is exceptionally challenging to test in practice. For addressing this key challenge, here we propose a criterion based on the logical contradictions of weak entanglement, which may boost the sensitivity of the signal due to the gravitationally induced entanglement. Specifically, we make use of the weak-value scenario and Einstein-Podolsky-Rosen steering. We prove that it is impossible for a classical mediator to act on two local quantum objects to simulate amplified-weak-value phenomenon in two-setting Einstein-Podolsky-Rosen steering. Our approach can amplify the signal of gravitationally induced entanglement that were previously impossible to observe by any desired factor that depends on the magnitude of the weak value. Our results not only open up the possibility of exploring nonclassical nature of gravity in the near future, but they also pave the way for weak entanglement criterion of a more general nature.