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arXiv · 1711.05955

Geometry of quantum correlations in space-time

Zhikuan Zhao·Robert Pisarczyk·Jayne Thompson·Mile Gu·Vlatko Vedral·Joseph F. Fitzsimons
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Abstract

The traditional formalism of non-relativistic quantum theory allows the state of a quantum system to extend across space, but only restricts it to a single instant in time, leading to distinction between theoretical treatments of spatial and temporal quantum correlations. Here we unify the geometrical description of two-point quantum correlations in space-time. Our study presents the geometry of correlations between two sequential Pauli measurements on a single qubit undergoing an arbitrary quantum channel evolution together with two-qubit spatial correlations under a common framework. We establish a symmetric structure between quantum correlations in space and time. This symmetry is broken in the presence of non-unital channels, which further reveals a set of temporal correlations that are indistinguishable from correlations found in bipartite entangled states.

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Zhikuan Zhao, Robert Pisarczyk, Jayne Thompson, Mile Gu, Vlatko Vedral, Joseph F. Fitzsimons. 2017-11-16. Geometry of quantum correlations in space-time. https://doi.org/10.1103/physreva.98.052312

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