Geometry of quantum correlations in space-time

• Main Authors: Zhao, Zhikuan, Pisarczyk, Robert, Thompson, Jayne, Gu, Mile, Vedral, Vlatko, Fitzsimons, Joseph F.
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2018
• Subjects: Quantum Correlations; DRNTU::Science::Physics; Geometry
• Online Access: https://hdl.handle.net/10356/89154; http://hdl.handle.net/10220/47047
• Institution: Nanyang Technological University

The traditional formalism of nonrelativistic 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 nonunital channels, which further reveals a set of temporal correlations that are indistinguishable from correlations found in bipartite entangled states.