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arXiv · 1312.5237

Quantum and classical capacity boosted by a Lorentz transformation

Kamil Bradler·Esteban Castro-Ruiz·Eduardo Nahmad-Achar
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Abstract

In this paper we show that the quantum channel between two inertial observers who transmit quantum information by sending realistic photonic wave packets is a well-studied channel in quantum Shannon theory -- the Pauli channel. The parameters of the Pauli channel and therefore its classical and quantum capacity depend on the magnitude of the Lorentz boost relating the two observers. The most striking consequence is that two inertial observers whose Pauli channel has initially zero quantum capacity can achieve nonzero quantum communication rates (reaching in principle its maximal value equal to one) by applying a boost in the right direction. This points to a fundamental connection between quantum channel capacities and special relativity.

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Kamil Bradler, Esteban Castro-Ruiz, Eduardo Nahmad-Achar. 2014-07-31. Quantum and classical capacity boosted by a Lorentz transformation. https://doi.org/10.1103/physreva.90.022308

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