# Quantum inequalities do not forbid spacetime shortcuts

@article{Krasnikov2003QuantumID,
title={Quantum inequalities do not forbid spacetime shortcuts},
author={Serguei Krasnikov},
journal={Physical Review D},
year={2003},
volume={67},
pages={104013}
}
A class of spacetimes (comprising the Alcubierre bubble, Krasnikov tube, and a certain type of wormhole) is considered that admits superluminal travel'' in a strictly defined sense. Such spacetimes (they are called shortcuts'' in this paper) were suspected to be impossible because calculations based on quantum inequalities'' suggest that their existence would involve Planck-scale energy densities and hence unphysically large values of the total amount of negative energy'' \${E}_{\mathrm… Expand

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