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Quantum limitations on superluminal propagation

Yakir Aharonov·Benni Reznik·Ady Stern
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Abstract

Unstable systems such as media with inverted atomic population have been shown to allow the propagation of analytic wavepackets with group velocity faster than that of light, without violating causality. We illuminate the important role played by unstable modes in this propagation, and show that the quantum fluctuations of these modes, and their unitary time evolution, impose severe restrictions on the observation of superluminal phenomena.

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Yakir Aharonov, Benni Reznik, Ady Stern. 1998-04-07. Quantum limitations on superluminal propagation. https://doi.org/10.1103/physrevlett.81.2190

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