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New Test Supports NASA's Controversial EM Drive
An anonymous reader writes: Last year, NASA's advanced propulsion research wing made headlines by announcing the successful test of a physics-defying electromagnetic drive, or EM drive. Now, this futuristic engine, which could in theory propel objects to near-relativistic speeds, has been shown to work inside a space-like vacuum. NASA Eagleworks made the announcement quite unassumingly via NASASpaceFlight.com. The EM drive is controversial in that it appears to violate conventional physics and the law of conservation of momentum; the engine, invented by British scientist Roger Sawyer, converts electric power to thrust without the need for any propellant by bouncing microwaves within a closed container. So, with no expulsion of propellant, there’s nothing to balance the change in the spacecraft’s momentum during acceleration.
I want a non-Newtonian drive as much as any other nerd out there, but it's still more probable that (assuming it works) it uses conventional physics, just in ways they haven't figured out yet.
That said, I think this result is the point where NASA, DOD, Lockheed Martin, Boeing et al should turn on the money spigot for research. There's obviously something going on, even if it's just conventional physics in unexpected ways. And on the odd chance it *is* new physics, the results could change the world.
Let's see: we can violate conservation of momentum by invoking some sort of vaguely defined quantum woo. Riiiight. Where do I send my check?
The practical result says that it works anyway.
I suspect that there is a balance in physics somewhere... just that no one knows where or what that is yet.
I am kind of curious though - does it have the acceleration curve of a VASMIR/Ion engine, or can we build something with it that will give greater speed in less time?
(...also, is the acceleration graph linear, curved sharply in either direction, hits a curve at a certain point... what?)
Quo usque tandem abutere, Nimbus, patientia nostra?
I suspect that there is a balance in physics somewhere... just that no one knows where or what that is yet.
This.
Just because we can't see the balance doesn't mean it isn't there.
This might be another Cold Fusion moment. Or, it might be the start of something very interesting.
When an experiment contradicts a theory, there are two possibilities: (1) there's something wrong with the experiment; or (2) there's something wrong with the theory. If the correct answer is (1), then it's par for the course: mistakes happen, and the process of science corrects them eventually. But if the correct answer is (2) then it's cork-popping time, because you have discovered new science.
If it weren't for deadlines, nothing would be late.
More like tests keep showing that it IS working, and nobody is sure why. Either the problem is with the test, or there's something else happening that we don't understand, but either way, nobody is sure yet what's going on.
I think it's likely that the test is faulty, but they need to figure out why or how the test is faulty.
Or, rather than all of physics being wrong, maybe they have an erroneous measurement setup.
That doesn't mean you shouldn't investigate anomalous measurements. But at this stage you shouldn't be writing fluff pieces with page after page of how much your new technology will change spaceflight. You should be publishing a paper with a name like "Measurement of anomalous thrust in a microwave apparatus operated in a hard vacuum" and trying to avoid the media insomuch as possible - and when you need to talk with them, trying to explain "we don't know what's going on... we have some theories but they're controversial... we need to do more testing." etc.
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If you learn of an alleged unusual phenomenon, and you have an immediate rigid response, please stay away from science. Go into religion or politics. The only appropriate response is "Hmmm interesting, let's look into this". Human knowledge is always provisional. Careless, absolute, knowledge claims are the currency of religion.
So you're one of the swags that believes all physics is right? Puh-leeze lets make up some more shit like dark matter an dark energy to make it so!
Any time you have an assumption based on physical laws, it must be able to be tested and measured and accounted for and predicted, and if the prediction based on those physical "laws" differs from what is observed, one must first, check their math for errors, check their method of measurement and if all of that checks out to be accurate to ask questions along the lines of: "What are the implications of what we have observed and measured and verified here?" or as Einstein asked "What would the universe be like if it operates the way we have observed it to here?" This is what allows science to side step conundrums based on incorrect assumptions and asking poorly worded questions that lead research astray and into asking the "Wrong questions". Before Einstein, the question was "Why does light always seem to be moving the same speed regardless of the point of view or movement of the observer with respect to that light, when we know that it can't?" That is a poorly worded question, because it assumes that what we know, but that we are unable to use to explain what we observe is correct, when it is likely it is not correct. This is why I hate the term "Laws of Physics" because it implies that they way we understand the universe is the way it operates, when these "Laws" are just our shorthand for documenting and understanding what we observe. This is also not to imply that when someone says "This breaks the laws of physics!" that they are pulling a James Dean, rebel attitude and getting something for nothing, it really, most likely means someone does not fully understand the thing they are dealing with and some corrections will be needed to science books of the future. As HAL9000 said in 2001, A Space Odyssey, "The problem can only be attributable to human error."
That is pretty close to what is going on.
There are now several experiments which confirm the production of thrust, many efforts to falsify the results, and a few efforts to come up with a theory which explains what we are seeing. There may be another test or two on the ground, but the first real space trial is likely coming soon. The only real way to be sure is to launch one and measure the dv.
I had the same thought they did initially, which is that convection of air was responsible for their thrust. That will not happen in vacuum, so that idea is right out.
This is a very promising experimental result, following several other very promising experimental results from different labs. I would say there is now serious evidence that this works, or at least that there is more to it than we can easily explain given our current understanding of physics.
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