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Warped space-time for phonons moving in a perfect nonrelativistic fluid

Uwe R. Fischer·Matt Visser
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Abstract

We construct a kinematical analogue of superluminal travel in the ``warped'' space-times curved by gravitation, in the form of ``super-phononic'' travel in the effective space-times of perfect nonrelativistic fluids. These warp-field space-times are most easily generated by considering a solid object that is placed as an obstruction in an otherwise uniform flow. No violation of any condition on the positivity of energy is necessary, because the effective curved space-times for the phonons are ruled by the Euler and continuity equations, and not by the Einstein field equations.

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Uwe R. Fischer, Matt Visser. 2003-03-23. Warped space-time for phonons moving in a perfect nonrelativistic fluid. https://doi.org/10.1209/epl%2Fi2003-00103-6

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