Mars in 70 day. Peer-reviewed paper!
Hmmm.
It would be easier to accept something that violates basic principles of physics (e.g. conservation of momentum) if its advocates would to take a crack at suggesting the new laws that now apply.
NASA has the money to mount this in a rocket and shoot it off into space just as an experiment, doesn’t it? Or, put a prototype EM drive in a smaller device and launch it from the space station, or something. It might not cost more that a couple of million dollars to do a practical test and prove/disprove the device.
Or contract it out to Jeff Bezos or Elon Musk. Especially Musk I would think would be very interested in it.
Bob
Send me a postcard from Mars. That’s how we will know it works.
In general, I don’t think that is a reasonable demand. If this thing works and can be reproduced consistently by third parties and they can build practical prototypes then I think they kind of win the argument, and the scientific community as a whole needs to come to terms with the fact that there is a practical demonstration that the theoretical models aren’t as good a model of reality as we thought.
And that’s not a big deal. I mean, its a big deal. But its not the end of science or engineering or anything. We’re still happy to use Newtonian laws of motion when they work, and stop relying on them when they don’t.
That said, if experimental results go against theories that have been tested and tested and tested in a huge amount of scenarios its reasonable to raise an eyebrow at their findings and remain skeptical until the evidence (from lots of third parties) becomes overwhelming that they’re correct. I’m not sure we’re there yet here, and if I was forced to bet I’d probably put money on this eventually being attributed to faulty experimentation. But maybe not, and that what vigorous testing by the scientific and engineering community is for.
I’m trying to think of a technology which defied accepted science and had to wait for the theory to catch up.
NO, Columbus did NOT prove that the world was round - that was already accepted (except for maybe God).
He just proved that an entire continent could be in the space he thought didn’t exist (he was WAY off on his distance calculations).
Maybe a vacuum was invented before the theory caught up?
As to “working model” in a rocket.
No. it would need to be deep space to be free of gravity. ISS is NOT free of gravity - anything orbiting is, by definition, within gravity.
Getting a few hundred kilowatts outside the solar system is not going to be cheap. There are, what - 2, maybe 3 probes in deep space?
I’m really not seeing the problem here. Energy is going in, and thrust results. Right?
What are you going to discover in deep space that you aren’t going to discover testing it in free fall?
Do you have some hypothesis that it only works in a non-homogenous gravity field?
Conservation of momentum. For any known propulsion system the increased momentum of the rocket (or the whatever) is mirrored by some sort of reaction mass gaining the same momentum in the opposite direction. It’s a basic law of physics. If this actually works as advertised, it breaks that law and it could be a window into the underlying fabric of space-time.
I don’t see how it breaks conservation of momentum. After all E=mc2+kmv2, right? The second term being momentum. Fight my ignorance here.
Take a traditional rocket. For simplicity’s sake say that we use the reference frame where it has no momentum at t=0.
Then the rocket system, i.e. the rocket and anything it sends out such as rocket exhaust and photons, will always have a total momentum of zero.
If the main body is given the momentum p then it has to send out something with momentum -p to keep the total 0.
This particular EM drive sends out nothing, and so, if it actually works, violates this fundamental law.
Each sequential atomic theory. The path from “little spheres” to “probabilistic wave-particle functions” didn’t take very long once we started on it seriously, but each step of the way was triggered by Yet Another Unexplainable Piece of Reality. Said path involved, among other things, the invention of the cathodic tube which used to be inside every television.
So how do they know the reaction force isn’t turned 90 degrees, sort of like pushing in on a wedge from both sides which moves it in towards wider end?
If I understand your question correctly, when they tested the engine on the torsion pendulum one of the test was along the axis with negligible results.
It’s interesting. At least now there’s something others can build, testing and evaluate on their own.
I figured they weren’t idiots and did try to look for an explanation, I’m just curious how such things are tested. I assume they’ve tried different chamber shapes also to try to explain it. But it wouldn’t be the first time scientists forgot to look at the obvious, even when I was a little kid polywater was supposed to be a materials breakthrough and turned out to be nothing but contamination. Then we had cold fusion too. Of course Newton has proven wrong before, not so much totally wrong, but the picture turned out to be bigger than we thought.
The paper is here - http://arc.aiaa.org/doi/10.2514/1.B36120
Enjoy.
They haven’t been looking to explain anything yet. The first step was to “confirm” there was anything to explain, which they’ve done to the best of their ability within the very low budget.
And changing the shape of the chamber won’t make it not violate conservation of momentum.
In the Discussion section toward the end of the paper, they do engage in some theoretical speculation. Nothing that rises remotely to the level of “explanation”, but they discuss pilot wave interpretations of QM, and a macroscopic experiment that apparently lends some plausibility to the notion of a pilot wave. And finally,
But, certainly, I agree with others that it’s way too early to think about new physics. We need to be sure there’s a real effect before there’s any need to postulate a mechanism, and we’re nowhere near reaching that burden.
Has anyone tested these in an electromegnetic anechoic chamber, to eliminate the possibility that the device is interacting with the metal chamber through electric and/or magnetic fields?