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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
... or can ye?
Eagleworks is in the usa.
It was also given limited testing in Europe.
The arguments against the drive depend on which of the three suggested explanations you like to prefer. Aside of course from the lame dogmatic ones that is.
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.
Can we all just take a moment to acknowledge how awesome Guido Fetta's name is?
Learning about brewing beer, by brewing beer.
Photons dont leave except via blackbody radiation. Pointing the magnetron that drives it out into space would be more efficient if it worked the way you suggest.
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 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
It's a closed chamber. Try reading something (anything) before you comment next time. Thanks.
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
To be clear, the hoax part is that emdrive cannot be explained by the laws of physics. The fact that photons can push is real. It has been measured. Simply apply newton's third law - for every action there is a reaction - and you get emdrive. But, the engineers will probably show that the force is too small. The sun's illumination in space is very strong and it only pushed the satellites a few miles over several days?
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.
You hand in your nerd card right now. Star Trek's impulse drives are magnetoplasmadynamic thrusters powered by deuterium fusion reactors. Basically, they do eject mass.
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I've been following emdrive for a while now. Prof McCulloch's book and emdrive paper provide the best description I have yet seen of an emdrive. As mentioned above there are no 'laws' of physics, just a collection of theories which seem to describe observed facts well. The theories change or are expanded to suit fresh observations. The best theories can be used to make predictions and provide explanations in disparate other problematic observations and this is the case with Prof McCulloch's work.
If NASA are prepared to use resources to send one of these things to orbit then the case for emdrive is at least still open. Speaking personally, I would like to use a 3d printer to build a 10x10x10 Cu block of these cavities, that should give a definitive answer. How about it Mr Musk?
Problems always arise on the edge of physics from the difficulties of making measurements. That's the fun of the thing...
I am pretty much the opposite to a blind status-quo defender or repeating-what-many-say parrot (some of my previous comments here give a good proof of it), but you have to draw the line somewhere.
If something works in certain way over 99999999999999999999999999999... (much bigger than that, virtually an infinite number; all the physical phenomena agreeing with classical mechanics during the last hundreds of years!!) times, you build a solid theory fully explaining it and, suddenly, you find one case going against such a theory, the most logical behaviour is assuming that you made a mistake in that one case. A different behaviour would be indicative of either ignorance or disproportionate/dreamy/delusional expectations (subtype of ignorance in its widest sense) or a hidden interest. On the other hand, any sensible person should be able to differentiate between theory explaining a given phenomenon and the phenomenon itself and, consequently, shouldn't find any problem to disprove/update/extend the applicability of a theory as soon as needed.
Even in case of having actually working prototypes (lots of them, under many different conditions and always delivering the expected output), I wouldn't be sure about its validity until after having properly understood the reasons for such a behaviour (or, at least, having a huge number of always-working empirical results). Even by assuming that all this is in place, I wouldn't ever dare to (linearly, exponentially? what is the magic here?) extrapolate conclusions from such an exceptional and non-understood phenomenon to completely different conditions. For example: if I have proven that this approach can be as fast as 1 cm/s, for up to 1 hour under highly controlled lab conditions; how could I dare to conclude what might be its performance in a completely different situation (reaching Mars in x time?!). This wouldn’t make any sense even when dealing with fully understood phenomena. "Scaling up" isn't scientific/physics/engineering talk, but business talk. What works in certain way at 1 doesn't have to work at 0.00000000001 or at 10000000000. In fact, we know the applicability of such a statement to mechanics since over 100 years ago (side note: I am certain about the multiple errors of some of these old implementations, but also about the validity of their underlying ideas; that is, our theories can only be applied within very restricted conditions), how could anyone dare to contravene such a reality too?
In summary, I think that all this EmDrive ideas are a pure nonsense (e.g., the original theory being shown as a game-changer with no explanation and virtually no validation; talking about investing so much money in such a thing; scientists accepting "it shouldn't be and I don't understand it, but will throw it out there just in case", etc.). I am very far away from being the typical naysayer/against-progress person, but for me this whole idea is completely preposterous and represents a new example of (capital-, media-, ignorance-, other-? driven) pseudo-science.
Custom Solvers 2.0 = Alvaro Carballo Garcia = varocarbas.
The power in solar radiation is moderate, but due to the extremely high velocity of photons, the associated force is very small. 9.08 micro newton per square meter (wikipedia), (about 2 micro-pounds-force per square meter)
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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.
Sure, but on Star Trek they can arbitrarily convert energy into mass so to refuel you just tell the replicator to make a few tonnes of deuterium and then transport it into the tanks. If we had that technology then a drive that uses no reaction mass wouldn't be as important.
Enigma
GGP's post contains nothing but the ST reference and paranoia about chinese research.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
I don't think that that ("blackbody radiation!) means what you seem to think it means. Blackbody radiation is composed of photons. (At least until you get into the tens of millions of Kelvin, when you might have spontaneous conversion of some of the photons into electron-positron pairs.)
Nice piece of buzzword biscuit you've got there. Flour, bread, and an oven for 25 minutes? Anything more substantial to it?
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
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).
But inertia is not a force.
Is that what Darth Vader meant by the dark side of the force?
Could you please explain how all the engines you refer are supposed to deliver movement? All of them, equivalently to everything moving everywhere (until apparently now) apply conservation of momentum/energy.
On earth, we have friction and this (well, together with quite a few other things) is what allows, for example, the engine to ultimately move the car (or you to walk). The engine moves the wheels and its rotational movement is converted, via friction against the road, into the linear movement which you see. For all this to happen, there have been a set of connected movements, each of them triggering the following one (gas pedal -> engine pistons -> wheels -> car moving forward, etc. An extremely summarised version by bearing in mind that all this happens at the microscopic level; for example: all the chemical reactions after burning the fuel). The lack of friction in space is what brings reaction into picture; but the story doesn't change: a movement is always triggered by another movement. Or using different words, energy cannot be created or destroyed, only transmitted.
As per our current understanding of nature, any phenomenon against the conservation of momentum/energy is pure magic.
Custom Solvers 2.0 = Alvaro Carballo Garcia = varocarbas.
That would not work though. Deuterium fusion reactors work by turning mass into energy; they are just not very effective at it. Most of the mass is still there after the fuel has been burned. Using energy from them to produce deuterium would be rathercounter-productive.
(Coal fired power plants turn mass into energy as well, but they are even worse at it).
Finally! A year of moderation! Ready for 2019?
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.
When you burn a fossil fuel (or anything actually) you don't lose any mass. Any energy released comes from the chemical reactions which are the bonds between electrons being broken and created. Fires are able to occur when there are reaction(s) that are exothermic (heat releasing) enough.
It is an unfortunate phrasing that nuclear physicists and engineers use the term burning in a nuclear reaction even though it has nothing to do with fires as most people understand it.
It's not meant to leave the ground. It's meant to give thrust to items already in space. Like ion drives or solar sails.
Any energy released comes from the chemical reactions which are the bonds between electrons being broken and created.
The reaction products have a mass that is ever so slightly lower than the mass was before the reaction.
A lot of online explanations get this wrong. Like this one: from the BBC, explaining conservation of mass in chemical reactions. It would probably unnecessarily confuse the students who focus on all the mass that a fire "loses" as CO2 and water vapour and such, which is not lost at all.
The mass loss is extremely small of course. For an energy release of 1J, you lose 11 femtogram (1J/c^2). Good luck measuring that on your high school scales, or indeed any scales at all.
Finally! A year of moderation! Ready for 2019?
... 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.
Late reply, but no, it means exactly what I think it means.
Any object with thermal excitation (warmer than absolute zero) that is composed of normal matter will emit infrared photons consistent with its temperature, in the form of blackbody radiation.
This device produces microwave photons using a magnetron. They bounce around inside a closed metal cavity. They do not escape (directly). However, this process heats up the cavity, which then does emit blackbody photons.
Again, the device does not emit the photons into space for propulsion. The only photons it emits are diffuse blackbody photons, as a consequence of it getting hot. If the device worked the way GP suggested, (emitting photons into space to leverage the relstivistic mass of the photons as a form of reaction mass), it would be more efficient to just point the magnatron out the back of the craft, rather than catch them inside a closed cavity, and force the energy to become diffuse blackbody radiation prior to emission.
The only one who did not understand that this is what was being stated is yourself.