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Time-reversal formalism applied to maximal bipartite entanglement: Theoretical and experimental exploration

M. Laforest·J. Baugh·R. Laflamme
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Abstract

Within the context of quantum teleportation, a proposed intuitive model to explain bipartite entanglement describes the scheme as being the same qubit of information evolving along and against the flow of time of an external observer. We investigate the physicality of such a model by applying the time-reversal of the Schrodinger equation in the teleportation context. To do so, we first lay down the theory of time-reversal applied to the circuit model and then show that the outcome of a teleportation-like circuit is consistent with the usual tensor product treatment, thus independent of the physical quantum system used to encode the information. Finally, we demonstrate a proof of principle experiment on a liquid state NMR quantum information processor. The experimental results are consistent with the interpretation that information can be seen as flowing backward in time through entanglement.

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M. Laforest, J. Baugh, R. Laflamme. 2006-04-03. Time-reversal formalism applied to maximal bipartite entanglement: Theoretical and experimental exploration. https://doi.org/10.1103/physreva.73.032323

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