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arXiv · 2311.08291

Distribution of quantum gravity induced entanglement in many-body systems

Pratik Ghosal·Arkaprabha Ghosal·Somshubhro Bandyopadhyay
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Abstract

Recently, it was shown that if two distant test masses, each in a spatially superposed quantum state, become entangled due to their mutual gravitational interaction, then this entanglement could serve as evidence of the quantum nature of gravity. We extend this treatment to a many-body system in a general setup and study the entanglement properties of the time-evolved state. We exactly compute the time-dependent I-concurrence for every bipartition and obtain the necessary and sufficient condition for the creation of genuine many-body entanglement. We further show that this entanglement is of generalised GHZ type when certain conditions are met. We also evaluate the amount of multipartite entanglement in the system using a set of generalised Meyer-Wallach measures.

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Pratik Ghosal, Arkaprabha Ghosal, Somshubhro Bandyopadhyay. 2023-11-14. Distribution of quantum gravity induced entanglement in many-body systems. https://doi.org/10.1088/1751-8121/ad82bd

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