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German Scientists Confirm NASA's Controversial EM Drive
MarkWhittington writes: Hacked Magazine reported that a group of German scientists believe that they have confirmed that the EM Drive, the propulsion device that uses microwaves rather than rocket fuel, provides thrust. The experimental results are being presented at the American Institute for Aeronautics and Astronautics' Propulsion and Energy Forum in Orlando by Martin Tajmar, a professor and chair for Space Systems at the Dresden University of Technology. Tajmar has an interest in exotic propulsion methods, including one concept using "negative matter."
Well NADA is an unlikely source for scams and it doesn't fit the pattern. The science behind it is openly shared without any secret sauce claims. The physics are uncontroversial.
The only thing there could be scam in is whether our engineering can really cash in on it.
At it's best its also not claimed to provide much thrust. You can't leave earth with it. But once you do even a tiny bit of thrust goes a long way. It's not even the only known way to get thrust without fuel - solar sails do that too.
I never got why so many people are so sceptical of this one. Engineering scams are nothing new but this breaks every pattern and the science is genuinely sound.
Unicode killed the ASCII-art *
This is the type of news I want to see more of. Between all of the pointless social narcissism platforms and SJW Bs this is enlightening news. I am excited to see what discoveries will be made. And if it turns out to be bunk, well who cares that's science!
What more do I need to say?
Eh... The physics mechanisms proposed ARE very controversial! The classic physics mechanism simply shouldn't work and the quantum physics proposal are far off speculations that aren't likely to be true.
But the amount of experimental verification from separate sources indicates that either there is some factor they all forgot or that there are new physics at play. I hope for the last alternative :)
A propulsion device that provides thrust without using reaction mass would be an earth-shattering advance, assuming the amount of thrust is non-negligible. I hope you do get that.
MythBuster's is so full of junk science that I feel dumber after watching an episode and find myself wondering things like the will the great ball of fire in the sky rise tomorrow and is the earth flat.
errr....umm...*whooosh* *whoosh* Is this thing on ?
I'm very hopeful this works. It's easy to be cynical, so I won't say "meh it's all bullshit!" Still, I won't be convinced until I see it provide thrust in a vacuum, away from Earth's magnetic field. It's still far, far too likely it's pushing off something terrestrial. So I'll give them a healthy "go, team, go!"
That said, quoth the article:
"This is the first time that someone with a well-equipped lab and a strong background in tracking experimental error has been involved, rather than engineers who may be unconsciously influenced by a desire to see it work," notes Wired referring to Tajmar's work.
I don't know about that. He is a real professor at a real university, but he also has filed for a patent on a gravity generator, using a process no one has duplicated. Somebody who thinks they've got a gravity generator, but gosh just can't prove it to everybody else, is definitely somebody who may be "unconsciously influenced by a desire to see it work."
We don't have a state-run media we have a media-run state.
In the conclusion section:
The nature of the thrusts observed is still unclear. Additional tests need to be carried out to study the magnetic
interaction of the power feeding lines used for the liquid metal contacts. Our test campaign can not confirm or refute
the claims of the EMDrive but intends to independently assess possible side-effects in the measurements methods
used so far. Nevertheless, we do observe thrusts close to the magnitude of the actual predictions after eliminating
many possible error sources that should warrant further investigation into the phenomena. Next steps include better
magnetic shielding, further vacuum tests and improved EMDrive models with higher Q factors and electronics that
allow tuning for optimal operation. As a worst case we may find how to effectively shield thrust balances from
magnetic fields.
Skepticism is healthy, and when something sounds too good to be true, it usually is. However, this is being repeatedly validated by multiple credible sources, which means that it should be accepted. If the crowd here is skeptical, it's only because we've see so much junk science over the years that has been latched onto and all the damage such things do. Look at the anti-vaccination movement, which has resulted in an increase in cases of diseases that were practically non-existent for decades.
Everything that's generally accepted today went through similar amounts of skepticism at some point and was borne out by repeated studies to prove its validity. Anything less and you've got something more akin to a religion and articles of faith.
something with a very long, low-thrust burn such as DS1's ion propulsion* and enough fuel to run for half a century maybe, Voyager 1 left the Sun's influence last year - nothing launched from Earth will ever catch it using gravity assists. New Horizons might be travelling at twice the speed of Voyager right now but it's not even 40AU out, by the time it gets to apoapse it'll be travelling slow enough to drop back - it's in a 100AU heliocentric orbit.
*the Dawn spacecraft, currently in orbit around Ceres, also uses ion propulsion - the same NSTAR 2100W engine as DS1, in fact.
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
Tajmar made a lot of hoopla over ten years ago about making gravitomagnetic waves orders of magnitude more powerful than GR predicted; some were claiming we were on our way to artificial gravity or a warp drive by his bold claims. Of course, his experiments could never be duplicated. Since then, he's been trying to make waves (ha!) with other dubious claims of making gravity effects by electromagnetic means and such.
Take anything he claims "confirmed" with a one hundred pound bag pinch of salt.
Ion thrusters still consume raw materials, so there's a finite fuel supply. If this does literally turn electricity into thrust without consuming anything then running out of reaction-mass is no longer an issue, and some probes could even be entirely solar powered.
Do not look into laser with remaining eye.
Neither Newton's nor Einstein's theory of gravitation were greeted with "extreme skepticism" by the general community.
Just thinking about this, how expensive would it be to create a small, simple satellite, with solar cells, some large LiPoly batteries, a transponder and an EM drive that fires up every time there is enough juice in the batteries to run it for a few minutes?
Sticking with the 50nN thrust level for 50W of input and assuming that a 1kg LiPol battery has 260Whr available (https://en.wikipedia.org/wiki/Lithium_polymer_battery), that is approximately 5hr of running time and assuming that the satellite is 5kg, there will be a 10nm/s^2 acceleration.
5 hours is 18,000s so there should be a delta-V imparted on the satellite of 1.8(10^-4)m/s which is tiny (I did say this is a pretty useless drive at the current time right now) but should be measurable or at least noticeable to its relative position to a control satellite that was launched along with it.
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Bad example. Light does exert radiation pressure, yes - but it is far, far too weak to drive a radiometer. The spinning radiometer isn't due to radiation pressure. It's a more mundane effect: Imperfect vacuum. The black side is warmed more than the white, which heats up adjacent air, which exerts higher pressure, causing the spin. It's just a plain old heat engine.
Until you travel at 0.7c and you discover the batteries are dead because solar isn't working at this speed so you cannot slow down.
Lifting its own weight is irrelevant. Existing electric propulsion thrusters couldn't come remotely close to lifting their own weight, and yet are still in active use in space.
It appears to impart momentum to something without an opposite momentum imparted to anything else... you know, the basic concept of how every other propulsion system in the world works?
When you walk, your feet push against the ground, imparting a (tiny, relative to the mass of the Earth) amount of momentum to it at the same time that your feet impart momentum to your body.
When you sail a boat, the sails alter the momentum of the wind, and an opposite alteration is imparted to the momentum of the boat.
When a rocket engine fires, it releases exhaust with a lot of momentum going one way, and the rocket receives the momentum going the other way.
This model holds for any kind of propelling of anything. Even a flashlight projecting photons imparts a tiny, tiny bit of momentum to your hand, to your body, to the earth. Magnetic propulsion, chemical propulsion, ion propulsion... all of them operate on the principle of "we go this way, by making something else go that way".
The EM Drive appears to go one way without making anything else go the other way. It releases no exhaust, pushes against no solid or fluid, emits no photons, and interacts with no external magnetic fields. We don't know how it works (there are a number of theories, none of which are that widely accepted), and we still aren't 100% sure it does work (maybe it's still all experimental error... that becomes less likely with each independent verification, but extraordinary claims call for extraordinary evidence), but if it does work it does so in a way that is outside our current understanding of physics. That is a Really Big Deal.
One way or another, this is exciting!
There's no place I could be, since I've found Serenity...
An ion thruster is a very efficient reaction mass based thruster,
It still has to drag all that reaction mass along, despite it's only real purpose being that it's thrown out like garbage just to provide thrust.
It takes thrust to push that reaction mass around the place, up until you actually throw it out the window, which is actually out the directed nozzle or whatever.
And what happens when you run out of reaction mass? You have no more thrust.
On the other hand, if you have a reactionless thruster, as long as you provide it with power, it will give you thrust. Slap on solar panels, or if it's a deep space mission, nuclear batteries or the like, and you are set.
As an added bonus, you can use that constant acceleration trick to really build up some speed. Something you can't do with reaction mass because you don't ever have enough, even for a tiny trip like to the moon.
The physics are most certainly NOT uncontroversial.
If this thing were to truly work, it would have insane implications to some basic assumptions about the universe - namely about the very laws of physics themselves.
This device working means that the laws of physics do vary by translation, which goes against every single other observation ever made. The science behind it is most certainly not clearly sound. Skepticism is the only logical option for this thing.
Scientists Confirm 'Impossible' EM Drive Propulsion
Science News, Space / July 27, 2015 / by Giulio Prisco/
Later today, July 27, German scientists will present new experimental results on the controversial, "impossible" EM Drive, at the American Institute for Aeronautics and Astronautics' Propulsion and Energy Forum in Orlando. The presentation is titled "Direct Thrust Measurements of an EmDrive and Evaluation of Possible Side-Effects."
Presenter Martin Tajmar is a professor and chair for Space Systems at the Dresden University of Technology, interested in space propulsion systems and breakthrough propulsion physics.
A Revolutionary Development for Space Travel
The EM Drive (Electro Magnetic Drive) uses electromagnetic microwave cavities to directly convert electrical energy to thrust without the need to expel any propellant. First proposed by Satellite Propulsion Research, a research company based in the UK founded by aerospace engineer Roger Shawyer, the EM Drive concept was predictably scorned by much of the mainstream research community for allegedly violating the laws of physics, including the conservation of momentum.
However, NASA Eagleworks – an advanced propulsion research group led by Dr. Harold G. “Sonny” White at the Johnson Space Center (JSC) – investigated the EM Drive and presented encouraging test results in 2014 at the 50th Joint Propulsion Conference.
White proposes that the EM Drive’s thrust is due to virtual particles in the quantum vacuum that behave like propellant ions in magneto-hydrodynamical propulsion systems, extracting "fuel" from the very fabric of space-time and eliminating the need to carry propellant. While a number of scientists criticize White's theoretical model, others feel that he is at least pointing to the right direction. The NASASpaceFlight website and forums have emerged as unofficial news source and discussion space for all things related to the EM Drive and related breakthrough space propulsion proposals such as the Cannae Drive.
Shawyer has often been dismissed by the research establishment for not having peer-reviewed scientific publications, but White and Tajmar have impeccable credentials that put them beyond cheap dismissal and scorn. Physics is an experimental science, and the fact that the EM Drive works is confirmed in the lab. "This is the first time that someone with a well-equipped lab and a strong background in tracking experimental error has been involved, rather than engineers who may be unconsciously influenced by a desire to see it work," notes Wired referring to Tajmar's work.
Hacked has obtained a copy of Tajmar's Propulsion and Energy Forum paper, co-authored by G. Fiedler.
"Our measurements reveal thrusts as expected from previous claims after carefully studying thermal and electromagnetic interferences," note the researchers. "If true, this could certainly revolutionize space travel."
"Additional tests need to be carried out to study the magnetic interaction of the power feeding lines used for the liquid metal contacts," conclude the researchers. "Nevertheless, we do observe thrusts close to the magnitude of the actual predictions after eliminating many possible error sources that should warrant further investigation into the phenomena. Next steps include better magnetic shielding, further vacuum tests and improved EMDrive models with higher Q factors and electronics that allow tuning for optimal operation."
Contrary to sensationalist reports published by the sensationalist press, the EM Drive is not a "warp drive" for faster than
There's no place I could be, since I've found Serenity...
It cannot be incomplete, it is a purely mathematical statement.
Particularly, for linear momentum, conservation of linear momentum is equivalent to the laws of physics being symmetric by translation.
If linear momentum is not conserved, the laws of physics are not the same throughout the universe and vice-versa.
Thank you for enlightening me. I read the wikipedia page on radiometers: https://en.wikipedia.org/wiki/...
I learned that radiometers do NOT work by "light pressure" which was Crooke's, the inventor's, hypothesis. Radiometers do NOT spin in a perfect vacuum. The two mechanisms that explain why they spin were proposed by the likes of Einstein (relativity guy), Maxwell (equations guy), and Reynolds (number, not aluminum, guy).
As an added added bonus, such a drive would accelerate faster at a given thrust, because of the absence of reaction mass. Conventionally, acceleration steadily increases at a given thrust as reaction mass is ejected, with maximum acceleration being reached just before reaction mass is exhausted.
We can dream, can't we?
Modern physics is never incorrect. Although it can be misunderstood at times. In the same way that relativity does NOT disprove Newton it confirms it, but extends it. Who would have thought that a little denominator with square root 1-(v squared / c squared) was missing, especially since if v = 0 then the whole denominator ends up being one...which means that all previous laws are valid exactly as they are. Science is not about great schisms where meanings and understandings are suddenly reversed from one generation to the next. That's politics and religion. Science is about progress, with every additional step necessarily building on the steps that were before it. Of course sometimes when you're standing a few steps higher up you get a better overall view of your surroundings and realize that maybe you were misinterpreting a few things before but now you understand them perfectly... until someone comes and puts another little step under your feet and you can see even further...
Seven puppies were harmed during the making of this post.
But I'll still be willing to listen to reasonable follow-up experiments instead of dismissing out of hand. So we get to Martin Tajmar and his claims (also not peer reviewed, but at least it's at a conference). Tajmar is not the guy I'd choose as the most reputable source. He has a history of claims about...creative physics from poor experimental setups. That is, he claims to observe new physics, but people have consistently had a hard time reproducing his results. Go ahead and google the guy.
I did, and appearantly it was Martin Tajmar himself, who found the flaw in his gravitational gyroscope thesis, and published it: FiberOpticGyroscope Measurements Close to Rotating Liquid Helium. So whatever you think about the guy, a superficial Google result seems to put him at least as honest. If he makes a mistake, he is able to admit it.
Here is the first page of the actual paper, including the abstract which says:
Our test campaign can not confirm or refute the claims of the EMDrive but intends to independently assess possible side-effects in the measurement methods used so far.
So the /. title says pretty much the exact opposite of what the actual
paper says.
I am still extremely skeptical that there is any actual effect. They powered their device with a 700 watt magnatron and measured plus or minus 20 micro-newtons of thrust. To put this in perspective, one Newton is roughly the weight of an apple near the surface of the Earth. If the thrust scales linearally with input power then you would need 50,000 x 700 Watts = 35 Megawatts to levitate a single apple. Of course the inventor claims that the thrust to power ratio is highly non-linear so at these higher power levels you would get a lot more thrust. I have not seen any sensible theoretical model that explains why this would be so.
If you are using hundreds of watts to produce a handful of micro-newtons then it is extremely likely there is no actual effect and what is being measured is just some form of noise. This is especially true when the so-called effect violates a primary law of physics.
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Someone needs a visit from Zombie Feynman!
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
You aren't following what he is saying--the research is saying is that THERE IS NO REACTION MASS. Per current physics, this device can't exist. That is why this is so big. No current physics explains it. It is not the opposite of a solar said, since the microwaves don't actual exit the device. If this device works, it does change everything, if only to point to new physics.
A ion drive requires reactionary mass to work.
I've been quoting Evola and Metternich to this bowl of water for hours now, how much longer until it turns reactionary?
Which is exactly why this should be presented as a breakthrough in physics with the standards of verification and publication used in physics rather than announced as a way to propel rockets. Using the standards of a breakthrough in physics, they have an anomalous experiment. Now they need to replicate it under more idealized conditions and then we'll evaluate whether to give them a Nobel Prize. Almost certainly this anomalous experiment will turn out to be an experimental error or misinterpretation since the theory of conservation of momentum they are claiming to violate is so extremely well corroborated.
People are so sceptical of this one because if true the implications are universe-shaking. It would completely overturn not just modern physics but all of physics since Newton. The claim is that the device violates conservation of momentum. Then via Noether's theorem this implies that the laws of physics are not independent of location in space. (Alternatively, the device is creating a beam of hard to detect particles via some completely unknown but low energy mechanism.)
Also, the device was first designed using a provably incorrect analysis - an analysis using standard physics determined that the device would produce thrust without reaction mass, violating conservation of momentum. As all the standard physics used in the analysis conserves momentum, the analysis must be incorrect. If someone adds up many even numbers and comes up with an odd total, we know they have made a mistake, even without examining their calculations to find out where. This case is exactly analogous. So if this device really does violate momentum conservation, it is a complete and utter fluke, and not by design.
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Looking at this another way:
When LHC were looking for the Higgs boson - a particle entirely expected by modern physics - they required a five sigma signal before they were satisfied that they had really found something.
This is a result not only entirely unexpected, but contradictory to almost all known physics. A two sigma (NASA) and three sigma (Germany) signal is not remotely enough to be convincing. At best it is convincing enough for someone to spend the money to further and better test it.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
I've been following this invention for years; since the first announcements from Shawyer through his being trashed by various physicists and wanna-bees, through his redemption through work in China and NASA. It used to be very difficult to get information, but since the burst of activity on the NASA Space flight forums, there's now too much information to digest, especially for someone like me who only has an undergrad level of schooling in it. If you want lots of details and discussion, check it out - but please don't post unless you really know what you're talking about, as there's already been a hell of a lot of noise. http://forum.nasaspaceflight.com/index.php?topic=37642.0
Conservation of momentum is more than "new physics". It's quite fundamental, thanks to Noether's Theorem: conservation of momentum is mathematically equivalent to "the laws of physics don't vary with spatial coordinates", that is, the X, Y, and Z axes can be "zeroed" anywhere, the choice of coordinates are arbitrary as long as their consistent. The universe would be a very strange place indeed if this weren't true, and furthermore we'd have noticed by now.
So, whatever's going on here, momentum is being conserved. Just how that's happening is the curious bit. It wasn't obvious until the early 1900s that light had momentum - maybe there's something else we're missing, or maybe this really is an actual "warp" drive that locally changes the metric of space (in a way different from GR) and momentum really isn't conserved. Somehow I doubt the latter is true.
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"Once you fire this husk of metal, it keeps going till it hits something. That can be a ship, or the planet behind that ship. It might go off into deep space and hit somebody else in ten thousand years. If you pull the trigger on this, you're ruining someone's day, somewhere and sometime....That means Sir Isaac Newton is the deadliest son-of-a-bitch in space."
"You saved 1968." - Ms. Valerie Pringle to the crew of Apollo 8
Photons have no rest mass. Their mass is entirely their energy. They do have mass.
This isn't new. They had to correct for Pioneers microwave thrust. Heat thrust is the accepted explanation for the Pioneer anomaly.
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I'm with you man, but this was exactly the same thing that people said when NASA confirmed the results. I was with you then too. Skeptisisism and all that.
The fact that the Germans now have also confirmed this is pretty huge. I'd say this moves out of the 'anomalous experiment' territory and more into the 'can we devise more and newer experiments to understand what the flaven is happening here' zone.
It's worth noting that there's a big difference between those theories and this engine. With this engine, they're putting forward a piece of technology and saying, "We don't know how this works, but we're claiming it does." In the case of Newton and Einstein, they put forward a mathematical model that was internally consistent, and the question was whether it applied to reality.
So in one case, they're putting forward a technology without a real explanation as to how it works, and in the other case, they're putting forward a coherent theory that seems to explain phenomena that we have witnessed. Also, both Newton and Einstein's theories had the benefit of providing a clean explanation to phenomena that we were having a lot of trouble explaining.