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NASA's Impossible Propulsion EmDrive Is Heading to Space (popularmechanics.com)
An anonymous reader writes:The EmDrive, a hypothetical miracle propulsion system for outer space, has been sparking heated arguments for years. Now, Guido Fetta plans to settle the argument about reactionless space drives for once and for all by sending one into space to prove that it really generates thrust without exhaust. Even if mainstream scientists say this is impossible. Fetta is CEO of Cannae Inc, and inventor of the Cannae Drive. His creation is related to the EmDrive first demonstrated by British engineer Roger Shawyer in 2003. Both are closed systems filled with microwaves with no exhaust, yet which the inventors claim do produce thrust. There is no accepted theory of how this might work. Shawyer claims that relativistic effects produce different radiation pressures at the two ends of the drive, leading to a net force. Fetta pursues a similar idea involving Lorentz (electromagnetic) forces. NASA researchers have suggested that the drive is actually pushing against "quantum vacuum virtual plasma" of particles that shift in and out of existence. Most physicists believe these far-out systems cannot work and that their potential benefits, such as getting to Mars in ten weeks, are illusory. After all, the law of conservation of momentum says that a rocket cannot accelerate forward without some form of exhaust ejected backwards. Yet the drumbeat goes on. Just last month, Jose Rodal claimed on the NASA Spaceflight forum that a NASA paper, "Measurement of Impulsive Thrust from a Closed Radio Frequency Cavity in Vacuum" has finally been peer-reviewed and accepted for publication by the American Institute of Aeronautics and Astronautics, but this cannot be confirmed yet.
Even if he sends this to space, the argument that it is leaking evaporated bits from the interior of the cavity will persist.
I expect others to follow.
Until he sends the damned thing on a tour of the solar system with no other forms of propulsion, where any such arguments would require the evaporation of significant portions of the cavity internals, and where both speedup and slowdowns happen, this will never be settled.
Before any else. Flux capacitor. Now.. on to conversation with some utility...
09 F9 11 02 9D 74 E3 5B - D8 41 56 C5 63 56 88 C0 45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
I'd laugh if it wasn't so on-the-nose. "Impulse drive" from Star Trek come to life?
I thought subspace was supposed to be fictional :P
But it could also yet be another Chinese research fraud.
... or can ye?
At this point, it seems that what is happening is a combination of two factors: 1) Experimental error. 2) Small amounts of material are being heated up and outgassed. This is consistent with an open cavity and is consistent with some of the reports having the drive's thrust take a small amount of time to start off, which looks a lot like it is taking time for the cavity to heat up.
even going to get off the ground on its own power?
BTW photons coming out one end don't make it a reactionless drive
Can we all just take a moment to acknowledge how awesome Guido Fetta's name is?
Learning about brewing beer, by brewing beer.
The laws of physics have changed so much in the last few thousand years, why do we suddenly think we are at the pinnacle of dictating the laws that govern the universe just because we haven't found anything contrary in the last few hundred years? Our laws of physics are based around our extremely limited observation of a tiny portion of the universe; surely when more is observed then some of the laws are going to change.
Science relies on an open mind and proof of a theory by repeatable experimentation so all the naysayers who instantly dismiss anything with even the remotest possibility of redefining one of these laws of physics cannot be truly called scientists and are no better than those that would dismiss the notion of there being no god just as easily.
Exhaust based systems are so 1960's anyway...
Everything I write is lies, read between the lines.
The press hype goes on despite results of two experimental results that clearly indicated the mythical drive to not thrust: A group of physicists at the university of Dresden measured miniscule thrust, but strangely enough the thrust went into the same direction when the "EMdrive" was rotated by 90. So they figured that what they measured was probably resulting from an interaction of the electric powering from the outside with the magnetic field of earth. They couldn't easily remove this probable source of error in their setup, but a chinese group of physicists managed to do so: They powered the "EM-drive" from a battery that was within the same enclosure - and voila - no more thrust to be measured.
It seems to me this is indeed the infinite improbability drive. If it actually propels something doe we care why?
Some drink at the fountain of knowledge. Others just gargle.
This is the kind of stuff that makes physicists moist.
This paper has a possible explanation that was ignored by the article. If the EMDrive works, then the same explanation likely also applies to some of the galactic rotational observations that are used to justify the need for dark matter.
http://arxiv.org/pdf/1604.0344...
Good thing it's not a rocket then.
-
After all, the law of conservation of momentum says that a rocket cannot accelerate forward without some form of exhaust ejected backwards.
Perhaps it's more of a guideline.
It must have been something you assimilated. . . .
Finally. This is the real test. I suggest they put a radio beacon on it that any ham can receive. Either the signal triangulates further and further away and fades, or it doesn't. Of course some people will never believe, and others will always try even if the thing remains mired in LEO, spirals in and burns up; but this needs to be done.
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
NASA's Impossible Propulsion EmDrive Is Heading to Space
It's not NASA's.
systemd is Roko's Basilisk.
NASA's Impossible Propulsion EmDrive ...
The output of which would be the Impossible Propulsion Force. Tom Cruise is ready and waiting.
It must have been something you assimilated. . . .
... of the trillions of endless assertions on the internet which neither create any nor meet any equal and opposite force, since they have no causal effect on reality. To resolve this discrepancy of pent-up psychodimensional energy, the universe has willed into existence such a drive tapping into a transdimensional energy portal releasing the pent-up energy of those assertions, thereby preventing a massive buildup which would eventually cause such a huge catastrophic explosion so as to render reality as we know it utterly destroyed.
Ah, the Universe.
Sent from my ENIAC
Science relies on an open mind
That definition doesn't fit any of the modern scientists I have read about, across a number of fields.
I thought the new way was to have a preconceived notion and bake your data to make it fit, or else just write so thickly the reader will think up is down by the end.
You can bet a lot of new interesting discoveries are being swept under the rug by people scoffing just as they did for the EM drive because they didn't believe something was possible.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Obviously this works because dark energy is pushing against dark matter. Prove me wrong.
Real rocket scientist here - this is a hoax.
Google "photons have mass" to verify that photons, emitted by this type of drive, have momentum. The momentum is small, so small you could never feel the photons impacting your face on a sunny day (what you do feel is the heat though).
However, in space the small push of photons on a geosynchronous satellite is strong enough that the force must be considered when predicting its future orbit. Even a big heavy satellite. Normally the force is calculated assuming the solar panels are pointing straight at the sun (for max power). If they are mispointed, the satellite orbit will be off by several miles after two weeks, since the satellite gets pushed sideways and backwards by photons instead of just backwards. The resulting change in the orbit has been used to estimate solar panel mispointing from the orbit (instead of sending somebody up in a rocket), so a command could be sent to the satellite to better aim the solar panel towards the sun.
That same "photon push" can be used by a microwave emitter as a sort of "rocket" engine without any mass being expelled. Just emit photons in the form of microwaves. No law of physics are broken. Would you get a lot of power? Probably not. But you'd get some.
Not all observable, repeatable phenomena can be explained yet. The random formation of DNA seemingly defies statistical probability, yet, it happened. Just sayin' here...
When the king heard the words of the Book of the Law he tore his robes.2Kings22:11
Because it cannae work captain!
IANAP (where the 'P' is Physicist in this case), but if the device somehow interacted with the earth's magnetic field, then it could be transferring momentum between earth and itself. If so, in space there might not be enough ambient magnetic field for it to work though.
Just the fact that it's using energy means that it's going to lose mass (a very small amount though, probably not measurable.)
Just radiating photons out in one direction should also produce some thrust.
I presume all the scientists saying this won't work have thought about these possibilities and ruled them out. I just haven't read anything explicit about them ruling those things out.
I suppose that there is a minute but non-zero possibility that it's accidentally stumbled onto some new physics, like maybe it's tapping in to dark matter and pushing that around.
In theory, theory and practice are the same; in practice they're different. (Yogi Berra & A. Einstein)
First off, if the engineers designing this thing are remotely competent there won't be any out-gassing.
Uncontrolled out-gassing is, and has since the beginning of the space age, been a really obvious problem. So it'll be designed from the get-go to avoid uncontrolled out-gassing.
It also doesn't have to be brought back to Earth to be weighed. Acceleration, if any occurs, can be measured pretty precisely. The degree of acceleration is a product of the mass and velocity of out-gassing.
If there is any observed acceleration you just have to wait until the amount of reaction mass necessary to account for that acceleration exceeds some reasonable amount and we're done - it works. No tour of the solar system necessary.
Minutus cantorum, minutus balorum, minutus carborata descendum pantorum.
They're not usually found to be wrong, but...the luminiferous aether would like a quick word with you.
Weaselmancer
rediculous.
It's a little strange watching all these "smart" people come on here thinking they can just figure the whole thing out then go back to whatever they were doing before stumbling on this story. Every single post here whether arguing against the drive or trying to explain it has already been addressed over the past ten to twelve years with the last six publicly accessible online on the dedicated NASA forums. A place where hundreds of individuals and teams from around the world that have built their own devices can discuss and share results and resources. They've been built in garages, labs with university teams and in the offices of major companies r&d departments. The people doing this range from particle physicists to aeronautical engineers, propulsion researchers and high school teachers. They've done this in damn near every country on earth and the one thing they all have in common is that they work. All of them. Yes, there have been design flaws, material failures and human error but the concept - like it or not - works. All these arguments you're making have been worked through and eliminated one by one over those long years. The only reason you're reading about it now is that all that hard work is now being detailed in a peer reviewed journal. That will enable the drive to finally go to space where it's proof of concept phase can be complete. Meanwhile those that are more comfortable with the status-quo will continue to stand on the sidelines insisting that things they don't understand are impossible and that anyone pursuing such things are fools. They'll throw out the occasional argument - that's already been disproven - and laugh at just how smart they were once the whole thing fails. Watching the solar system open up for human exploration with this new technology will be worth all of it though.
Can you fit "NASA" in the summary a little more, you fucking crackpot submitter? This is a stupid hoax. This isn't NASA. This is just some guy who rented a NASA lab space. Anyone can do that. Just stop. Stupid Space Nutters.
The "laws of physics" are man made and have been changed before.
Actually I would claim that most physicists view the "laws of physics" as the fundamental properties and behaviour of the universe and the energy and matter it contains. Our understanding of these laws (the human laws of physics if you like) is imperfect and has certainly changed in the past but, so far as we are aware, the laws of physics themselves are constant.
However that does not rule out the possibility that at some point in the future we might be able to change them. Since they are a property of space-time and thought to have arisen from the Big Bang it is conceivable that we could learn to manipulate space-time to change them...but at this point that is only a very wild idea that is more science fiction that science. However we cannot rule out the possibility.
Possibly more interestingly an relevant though is that this rive, if it works as advertized, breaks conservation of momentum. This conservation law results from a very important fundamental symmetry that the laws of physics (in the fundamental sense) are the same everywhere in space. So if this drive violates that law it means that this symmetry is not true and the laws of physics have to change as you move through space. This appears extremely unlikely since astronomers tell us that the laws of physics seem to work as far as they can observe the universe and such extraordinary claims will need extraordinary evidence to back them up.
Someone please explain to me why this drive continues to be shopped around as something that breaks physics; everyone seems damned and determined to interpret Newton's third law as dictating that only rockets meet the requirements of a propulsion device, in the face of pressure-driven engines (steam, and other pneumatic systems), internal combustion, both piston and turbine, and both cyclical and linear electric motors; hell, the way people want to interpret physics as applied to this drive proves sailboats, kites, and gliders impossible.
It's very, very simple. The emdrive is not a rocket, any more than any of those other things I mentioned. What's more, it is a force amplifier, not a primary source of propulsion. It bears far more resemblance to a transmission than to an engine or motor. Neither does it give something for nothing; it requires electricity to operate it, just like an electric motor. The force it amplifies is inertial in nature.
I suspect this will turn out not to work. That said, it did remind me of the New York Times article in 1920 saying that Robert Goddard was foolish to think that rockets could work in space (see e.g. http://www.popsci.com/military... for their 1969 retraction).
Eat a lot of cabbage and hold a BIC near the source of pressure release and behold the miracle. Future generations to come will be shitting and pushing further into the cosmos than has ever been envisioned.
In regards to b:
That's not what "law" means in the context of science. We probably should never use that word in that context at all, but hey, "3D TV", "AI"... not much hope for rigorous speech, I'm afraid.
I've fallen off your lawn, and I can't get up.
I had this (probably completely wrongheaded) thought:
In 2d, imagine a triangle. Shoot momentum-having things out of base with impulse T at a perfect perpendicular (for purpose of thought experiment), so base is pushed away from direction of shot with impulse -T. Say one hits mid-left-edge. Imparts some of its momentum, T, to the left/forward as U/V. then, because pool table, bounces to right edge in straight line. Hits, imparts some of its remaining momentum (T-(U+V), as W/X, to the right/forward. Then, again because of pool table, bounces back towards base, imparting some of its remaining momentum, now reversed, -(T - (U+W)), which we'll call Y. V and X cancel out because they are in the T direction. Total base momentum for this pass of momentum-having thing is then -T + -Y. The new bounce is the new T, and the cycle repeats. This can continue (in a vacuum) for as long as thing has momentum left to deliver and can follow these, or similar, paths.
A cone is just a 3D triangle in this model. More area, same concept.
Bottom line is that equal amounts of momentum against the sides (because of shots from everywhere on base, should average out) are lost, so momentum delivered to the back (the base) is always higher than momentum delivered to the frontal direction, as some is always lost to the side. So the device should move towards the direction the base is facing.
I will now wait patiently for someone to explain what I missed, of which I am quite sure there is something, because otherwise it wouldn't be me saying this.
I've fallen off your lawn, and I can't get up.
Lots of people blow millions and billions of money
on useless bets on cards/dice daily in Vegas.
If you justified all expenses Columbus would not have gone to America (though some think he had secret inside knowledge that it was there from the Knights of Templar maps from ancient stuff.
Fuck it, spend the cash, ask Bezos or any billlionaire to coff it up and if it works, he would be ultra rich, Bill Gates doesnt need that much money.
Liberty freedom are no1, not dicks in suits.
Nothing to something, well that breaks the laws.
Liberty freedom are no1, not dicks in suits.
... it will be reported as failing for all sorts reasons except the actual one ie. the detractors are correct, it's a theoretical impossibility. Too many careers on the line for anyone involved in the project to admit they were wrong.
"Consensus" in science is _always_ a political construct.