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Distributed entanglement as a probe for the quantum structure of spacetime

Pieter Kok·Ulvi Yurtsever·Samuel L. Braunstein·Jonathan P. Dowling
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Abstract

Simultaneity is a well-defined notion in special relativity once a Minkowski metric structure is fixed on the spacetime continuum (manifold) of events. In quantum gravity, however, the metric is not expected to be a fixed, classical structure, but a fluctuating quantum operator which may assume a coherent superposition of two classically-distinguishable values. A natural question to ask is what happens to the notion of simultaneity and synchronization when the metric is in a quantum superposition. Here we show that the resource of distributed entanglement of the same kind as used by Jozsa et al. [Phys. Rev. Lett. 85, 2010 (2000)] gives rise to an experimental probe that is sensitive to coherent quantum fluctuations in the spacetime metric.

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Pieter Kok, Ulvi Yurtsever, Samuel L. Braunstein, Jonathan P. Dowling. 2002-06-12. Distributed entanglement as a probe for the quantum structure of spacetime. https://arxiv.org/abs/quant-ph/0206082

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