This was 2006, but couldn't be reproduced by others so far.<p>I would consider this quantum gravity research by far more important and cheaper than the CERN experiments which got us the mass of the Higgs boson. So far only Podkletnov, Tajmar and de Matos worked on this.<p>Goff and Siegel 2004 on FTL "Faster Than Light":
“Current warp drive investigations [Goldin and Svetlicny, 1994] apply general relativity to try to produce spacetime curvature that propagates at superlight speeds. Special relativity is preserved inside the warp field, but the contents are perceived to move at FTL speeds from the external frames. Such a classical warp drive cannot avoid the temporal paradox (i.e, time travel). If quantum systems are the only system that permits backward-in-time causality without temporal paradox, then any rational warp drive will need to be based on quantum principles. This means that until we have a workable theory of quantum gravity; research into warp drives based on General Relativity is probably doomed to failure.”