EmDrive is a possible propulsion system granting no apparent expulsion of propellent. It has been reason of hot debate with strong criticisms from the scientific community championed by Sean Carroll and John Baez. Notwithstanding this, NASA went ahead performing in-depth experiments to test this technology. It was announced that, on December this year, a paper will appear in a reputable journal reporting on the last measurement campaign. But to today the paper leaked out on reddit. The results, at a first sight, appear to be striking confirming the effect, with all the possible mundane disturbing causes excluded. You can also find other material there as a small video.
I hope this will go properly evaluated by the scientific community moving to a more serious addressing of this effect.
Update: The links were removed from the subreddit’s moderator. I have copies of these files but I do not mean to publish them in any form.
Update: Here is the published paper.
There has been a lot of rumor on measurements performed by Eagleworks labs at NASA this spring. After that, NASA imposed a veto on whatever information should coming out about the work of this group until peer-reviewed work should have appeared. Most of the problems come out from the question of the EmDrive. This is a presumed thruster obtained by pumping radio-frequency into a cavity shaped as a closed frustum. This device has been largely dismissed by the physicists’ community due to a blatant violation of conservation of momentum. Such an object should stand still aside from known physical effects as Lorentz force or thermal thrust arising from heating of the cavity in the air. The claimed effect is really tiny standing on measurements that has been done since now and so, mundane explanations remain the most credited. Notwithstanding this, people at NASA have kept on working. This is testified by the recent posts by Paul March at Nasaspaceflight forum. Paul march is a member of the NASA group working on new propulsion technologies and what he is claiming is really striking. I report this here
where he claims that, notwithstanding all the precautions, they keep on seeing a thrust. They know perfectly that, for Maxwell theory, no thrust should be observed as stated by the following post
So, they see a thrust, after having removed all mundane effects, and the possible explanation for it is not classical electromagnetism as all said from the start. In particular, it is cited by the questioner the link to Greg Egan’s post explaining why there cannot be any thrust by known electromagnetism with this geometry (see Greg Egan’s post). I think that they will make their results known once the peer-review process will be concluded. I would like to remember that other NASA labs asked to concur to confirm their measurements.
This group also performed interference experiments on this cavity and observed an effect. If all this will be confirmed it will represent a breakthrough, not only from the technological side let me say, as a new physical effect will be proved at work with general relativity now to be experimentally managed on a tabletop device. Note that general relativity is always at work in this situation with a large density of electromagnetic energy as I also discussed here. It should be said that this has nothing to do with warp drive as conceived in Alcubierre metric and similar.
We hope to hear very soon from this group with more official channels. Surely, their results will provide a wealth of new avenues to pursue for research and technology.
Marco Frasca (2015). Einstein-Maxwell equations for asymmetric resonant cavities arXiv arXiv: 1505.06917v1