Quantum correlations beyond entanglement in a classical-channel model of gravity
arXiv:2205.15333 · doi:10.1038/s41598-022-22212-1
Abstract
A direct quantization of the Newtonian interaction between two masses is known to establish entanglement, which if detected would witness the quantum nature of the gravitational field. Gravitational interaction is yet compatible also with gravitational decoherence models relying on classical channels, hence unable to create entanglement. Here, we show in paradigmatic cases that, despite the absence of entanglement, a classical-channel model of gravity can still establish quantum correlations in the form of quantum discord between two masses. This is demonstrated for the Kafri-Taylor-Milburn (KTM) model and a recently proposed dissipative extension of this. In both cases, starting from an uncorrelated state, a significant amount of discord is generally created. This eventually decays in the KTM model, while it converges to a small stationary value in its dissipative extension. We also find that initial local squeezing on the state of the masses can significanlty enhance the generated discord.
8 pages, 5 figures
References in corpus (9)
- A Spin Entanglement Witness for Quantum Gravity
- Gravitationally-induced entanglement between two massive particles is sufficient evidence of quantum effects in gravity
- Linking Quantum Discord to Entanglement in a Measurement
- All non-classical correlations can be activated into distillable entanglement
- Gravitational Decoherence
- Quantum discord bounds the amount of distributed entanglement
- Principle of least decoherence for Newtonian semi-classical gravity
- Quantum correlations in separable multi-mode states and in classically entangled light
- Lyapunov equation in open quantum systems and non-Hermitian physics
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