# 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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