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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."
A propulsion device provides thrust? Whatever next!
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Maybe this will be one that turns out not to be a scam...
told all y'all non-believers!
I am going to go check starcitizen website to see if this has been implemented yet.
Until Mythbusters confirms it, I'll just say it's Plausible.
Harrison's Postulate - "For every action there is an equal and opposite criticism"
You are all cows. Cows say moo. MOOOOOOOOOOO! MOOOOOOOOOO! Moo cows MOOOOOOOOOO! Moo say the cows. YOU COWS!!
If you don't need to carry propellant, not only can you get to Pluto in 18 months, you could probably decelerate and get into orbit. This could make for some exciting exploration of our solar system. And maybe we can catch/pass Voyager with a new interstellar probe?
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!
I don't understand how carrying and burning all of those microwaves would be better than rocket fuel, especially with the production cost of making the microwaves.
It's amazing how little science exists within science these days. Everyone has lost touch with reality.
What more do I need to say?
This is really amazing and hopefully it is turning into a window into parts of our universe that we've never imagined.
But, reading the articles, I think we're a long way off from understanding what this phenomena is and how to exploit it practically. Going back over the previous articles, the measured force was for 50 uN from 50W of power - this doesn't seem like a very practical application as yet; the claims of round trips to Mars in less than a year are very exaggerated.
On that point, I thought we could go to Mars in 3 months or so now; it just takes a nuclear rocket rather than chemical, plasma or EM drives.
Finally, in the hacked.com article, rather than expelling "propellant", aren't you expelling "reaction mass"?
Mimetics Inc. Twitter
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.
To paraphrase Charles Fort (blessings upon his name) It's spindizzies when it's spindizzy time.
Read the CE3 reports. Pay attention to how these "advanced" "aliens" behave. Not the sharpest crayons in the bag. If they can figure out interstellar transdimensional travel, it's not that hard. We just haven't looked in the right place.
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.
F=MA
The mass at either end is different. Force acts over an area, both ends have different areas.
Motion is expected.
If somebody still has the article on their screen, please post a text copy-paste.
If it weren't for deadlines, nothing would be late.
I don't understand why this is so 'unbelievable'. We have had methods of providing thrust in space without using rockets since 1916, the year the first ion thruster was built. Both use electricity to produce thrust.
What is bugging me is that every article about this 'em drive' claims that it doesn't use any fuel, it makes it sound like a free energy machine. Is electricity not a fuel?
What I would like to see is a comparison between this new 'em drive' and an ion thruster. How much electricity they consume for the same amount of thrust, which accelerates faster, etc.
Until then I can't really get excited about it. It might be a new method of propulsion, but if it is inferior to other methods we have had for nearly a century, what's the point?
https://en.wikipedia.org/wiki/...
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.
"...Tajmar has an interest in exotic propulsion methods...". Look up the BBC episode of "Heretics of Science" about Professor Eric Laithwaite.
researchers in India are experimenting with the imact of a transverse magnetic field, creating a "Tajmar-Hall" effect...
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.
Mimetics Inc. Twitter
I am a scientist and this is BS!
Why are we even allowing these heretics to 'test' this pile of blasphemy?
Science demands the we expel these infidels!
BURN THEIR PAPERS!!! DENY THEM GRANTS!!! REVOKE THEIR DEGREES!!! FIRE THEM!!!
Was this not invented by a limey that got upset at the west for not looking at it, so took it to china? Or was that something else?
I prefer the "u" in honour as it seems to be missing these days.
This is how it begins
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...
It sounds like they've been shielding it against external fields including the Earth's magnetic field but how do you shield it from gravity. I hope they can do an experiment in space ASAP.
I know this is Slashdot, but the abstracter of the paper is pretty clear:
"Our test campaign can not confirm or refute the claims of the EMDrive"
http://arc.aiaa.org/doi/10.2514/6.2015-4083
How did we get from that to the summary posted here? Why does the happen every single time an article about this appears on Slashdot?
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...
Try looking up "N rays" for an ancient example of how scientists can fool themselves.
Confirming propellantless thrust from a 2nd Generation superconducting EM Drive would outweigh local effects. (http://emdrive.com/secondgenengines.html) 2G (2nd Gen.) testing started in 2006, according to Roger Shawyer's paper: http://www.emdrive.com/2Gupdat...
How is this any better than firing a laser out the back of the drive? Can't create momentum out of nothing. Does a KW of microwave photons provide more thrust than a KW of (say) infra-red laser photons?
EM drive. You are making a magnet except not with magnetism. you are causing the engine to move towards something it is attracted to. that something could be infinite distance away. is the engine direction?
You are setting up some type of gradient. small amount of radiation particles on one side, large radiation particles on the other. it causes them to repel? if you have an opening, then this causes trust.
radiation particles just want to move away from each other. its like pumping air into a balloon, but its an infinite amount of radiation particles?
AIAA PROPULSION 2015, Propulsion & Energy Forum of the American Institute of Aeronautics and Astronautics in Orlando, FL
Wednesday, 29 July 2015: 129-NFF-5 0900 - 1200 hrs
Conversations in Breakthrough Propulsion Physics: Gravity
Round table members:
Dr. George J. Williams, Senior Scientist, Ohio Aerospace Institute, NASA Glenn Research Center
Prof. Martin Tajmar, Dresden Univ. of Technology, Dresden, Germany
Dr. Bryan A. Palaszewsk, Senior Scientist, NASA Glenn Research Center, Cleveland, OH
"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."
https://www.reddit.com/r/EmDri...
I wrote a comment on this up above, but just to help you understand...
1) No, the ion drive does not use electricity to produce thrust. Ion drives, as their name suggests, use ions to produce thrust. The ions are accelerated using fields generated via electric power, but that's no more a case of using electricity to (directly) produce thrust than an electric car is (the car pushes against the road, imparting momentum to the earth which balances the momentum imparted to the car).
2) Yes, it sounds like a free energy machine. If a given amount of electrical power produces a given thrust, constantly, without consuming any fuel, then you can generate unlimited energy by attaching this thing to a flywheel or rotor arm that drives a generator and it will produce more energy than it requires to drive the thruster. Some of the current theories about this thing claim that it won't do that, that its efficiency will go down the faster it's moving (relative to a given frame of reference).
3) No, electricity is not fuel. Electricity is not a thing. It is a process. Electricity is the motion of electrons. It is a form of energy. Fuel is a way to store energy, but it is not energy itself. You can generate electricity from many things, including fuel, and there are many forms of chemical devices with electrical potential energy - we usually call them batteries - but electricity is not, itself, fuel. Now, the energy still needs to come from somewhere (unless this drive does turn out to be usable to get more energy out than is put in, which would turn *all* of physics on its head) and that "somewhere" is usually fuel of some kind... but it can be things like uranium in a nuclear reactor that is usable for decades from a tiny amount of mass, or hydrogen in the sun producing photons as it fuses and those photons being captured and used to move electrons via the photoelectric effect (in layman's terms, solar panels).
There's no place I could be, since I've found Serenity...
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.
We don't see the world as it is, we see it as we are.
-- Anais Nin
Put it on a cheap and simple satellite, piggyback it on another satellites launch and run it for a few months/years. From what I understand this thing has such a small thrust that its difficult to differentiate between any possible thrust and instrument noise (earthquakes, cars/trains driving by, magnetic fields, etc). A real world test where a craft with no other means of propulsion can/can't change its orbit is the only way to be sure.
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?
Have gnu, will travel.
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.
If this data were at all convincing and held up to review, we wouldn't be reading a second hand report from Hacker News Magazine. This would be the cover article of Nature or Science. The editors would be fighting to have it.
There was a similar set of claims roughly 60 years ago for the "Dean Drive" a "reactionless drive" that did not seem to use propellant. To casual review, and letting it push your hand, it seemed to work, and a great campaign for research and to ignore the sceptics of the time was headed by John W. Campbell, the editor of Analog magazine. Analog was, and remains, a science fiction magazine specializing in hard science and science fiction based on it, and it had many real scientists as readers and contributors, so the Dean Drive received quite a lot of attention.
The Dean Drive has since been pretty thoroughly debunked as an "oscillation thruster", a device that relies on tuned "slipping" on the floor it rests on to creep forward and even to provide a modest thrust, _pushing against the floor_. The designer was never willing to allow a full "pendulum" test, or careful testing outside of his own workshop, and there seem to be dozens more of similarly patented "reactonless drives". The ones that work at all also seem to be "isicllation thrusters", pushing against the floor or the mehanism in which they are mounted.
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
Imagine all the burritos that could be heated up with this.
It's a radio transmitter feeding a closed waveguide. One has to ask: why haven't we seen evidence of radio transmission providing thrust before, when it's been feeding an open waveguide?
Bruce Perens.
but the approximations keep getting better
Every post here are ignoring that there's THREE types of engines they are talking about. An ion thruster has reaction mass and expels atoms rearwards, i.e. solid fuel. It may be able to scoop this fuel up, but yeah, it's a standard engine.
A photonic rocket does not use reaction mass, and expels massless photons, i.e. radiation. You simply heat something, and the heat emissions generate opposite thrust. This generates thrust as photons lack mass but do have momentum, relating to the Planck length. The problem with photonic rockets is that this is REALLY REALLY LOW. Quoting Wikipedia: "If a photon rocket begins its journey in low earth orbit, then one year of thrusting may be required to achieve an earth escape velocity of 11.2 km/s if the vehicle is already in orbit at a velocity of 9,100 m/s"
The EMdrive does not require reaction mass, and simply expels microwaves which are kept in a resonant mode inside a chamber made of copper. The theory is that they basically push against _something_ like irregularities in space, or a virtual quantum plasma, or whatever. Remember that the casimir effect is already mainstream science - pairs of virtual particles appear and disappear - so there's at least something weird with space itiself. But anyway, it's similar to a photonic rocket in that it doesn't use reaction mass, but far, far more efficient and thrust-generative based on early signs.
It was created by an independent inventor in the UK. It is insulting to all of science to act as though a large organization like NASA is capable of breakthrough physics when literally all breakthrough physics has come from individuals.
"Modern physics is never incorrect"
That's religion not physics. Quantum Mechanics is like the scientology of physics. Clearly disprovable with simple thought experiments, but each time they need to ignore something (e.g. violation of causality) they do so like brainwashed zombies. i.e. its flat wrong and provably so.
Some science e.g. String theory gets silently ignored till it fades away then forgotten about.
You realize that Einstein may be wrong? He's become sort of a god or prophet figure, but that doesn't mean he was right.
Question everything, re-examine everything. in the light of new information is what science is.
I would imagine that if you have a strong inhomogeneous magnetic field, you could rip out particle-antiparticle pairs, and move them as a group before they recombine, in which case you've exerted momentum on massive particles, independent of the fact that the momentum of their individual reaction is conserved. I can only picture this working though if you ejected the particles out the back. The contraption is apparently entirely closed.
It should be possible to construct a relatively low cost probe, making use of this new EM drive and the interplanetary transport network, to test this new concept. First, use the aforementioned interplanetary transport network and gravitational slingshots to place the probe on a solar escape trajectory. If the new drive actually works, then we should be able to, over a period of years and decades of interplanetary and ultimately interstellar cruising, to detect the acceleration of the probe as the EM drive continues to provide thrust in the absence of chemical propellent or anything to "push off against". The initial experimental results, both promising and controversial, seem to be enough to justify the cost of such a real world test. NASA ought to put together a proposal and budget a modest amount for this mission.
Acceleration is limited as much by available energy and limitations of materials as by the propellant. One can in theory shoot out a few particles at close to speed of light and accelerate arbitrarily fast. Or just shoot out lots of photons in one direction and move around "without propellant". This new drive has to not just work, but be more efficient than anything else we know. Else, it might well have some interesting science, but not be practically useful.
hey, that's recycling too, right?
> Hacked Magazine reported that a group of German scientists have confirmed the EM Drive ... ... in 1944 and have been using it ever since at their Neu-Schwabia base in the Antartica to power the Reptile Reich's Vril and Thule flying saucers. In other news, the Pentagon has classified all documents pertaining to Admiral Richard E. Byrd's 1947 southern naval aviation expedition for a further 100 years, in response to a recent FOIA request filed by Iron Sky AG and the Hollow Earth Society of America.
(By the way the Slashdot webform capthca for this posting is "fantasy". Apparently the publisher subscribes to the theory of ostrich's denial efficiency!)
A car moves by pushing against the ground.
A rocket engine works by throwing fuel in one direction so the rocket goes the other way.
A boat prop works without throwing fuel overboard by accelerating the stuff around it.
This gadget appears to work inside a metal box.
That should eliminate the ability to push, throw or accelerate classic stuff (matter) outside the box.
Yet, the whole box appears to want to move. Curious.
It might be pushing against some external field.
Presumably, the experiments eliminated the Earth's magnetic field.
Or it might be accelerating something that can go through the metal box.
Or perhaps these two effects might be the same thing?
If it is real, it may teach us something new about how things work.
That may turn out to be more interesting than having a new kind of space drive.
We're assured there's dark matter everywhere, maybe 5x as much dark matter as normal matter. What if these guys have found a way to interact with dark matter, essentially pushing on it?
It seems like dark matter has mass, and momentum, but it interacts poorly with regular matter. If you were pushing on dark matter somehow, it could just fly out of the chamber. Suddenly your "reactionless" drive is just another rocket that's using particles that happen to be around to push on.
However, if EM waves could interact with dark matter in any way, it shouldn't be "dark". You should see signs of interaction on cosmic scales or near very intense light sources like black holes, right? Or would the influence of such interaction be so small compared to gravitational redshift that it couldn't be noticed?
--PM
And I agree, this evidence isn't yet.
The forces generated are currently just too small to trust, and within the realm of experimental error given that they're within an order of magnitude of the noise. I'll only start getting excited when they scale up to measurements which are at least a few orders of magnitude above the noise threshold.
I think it's theoretically possible, but you some technique a lot more efficient than a Penning trap.
I wonder if the mass of the device changes after operating a while. Lets say the change of mass in the larger back plate is bigger than the the change in the smaller one, that would respect the conservation of momentum, and explain the thrurst (thrust will arise from the need to accomodate the difference of mass in the plates).
'Tajmar has an interest in exotic propulsion methods, including one concept using "negative matter."' -- is this what they mean by "it matters not" ?
but then IANAP. So there may be things I don't know about that render the following reasoning untenable.
Black holes "radiate" via virtual particles, whereby a virtual pair comes into being close to the event horizon. One of the pair falls into the black hole, while the other goes free. Thus the black hole "loses" a particle.
If you could somehow make sure the black hole "radiates" only in one direction, you could propel the black hole in the other. In inverse proportion to the masses, obviously.
So if virtual particles are created by the microwave drive somehow, then one particle stays with the drive, pushing it one way, with the other particle going in the opposite direction. Again it's in inverse proportion. You just need a whole lot of them, all going in one direction.
This is analogous to New Horizon's EM drive, only there you use xenon atoms as propellant, which are a whole lot heavier. The xenon atoms go one way, the craft goes the other. Energy is needed to form the xenon ions, propel them in one direction, and recombine the ions with electrons just before they leave the craft.
Seems to me this doesn't violate any laws. Momentum is conserved, starts with zero, ends with (a sum of) zero. Energy is required to keep the virtual particles going in one direction (and to accelerate them, I assume). So you still need energy; what you don't need is propellant. In New Horizon, the supply of xenon is limited. With the new drive, the supply of propellent (virtual particles) is unlimited.
Unless, like in Charles Sheffield's Novel, "Godspeed," the vacuum store of virtual particles is a resource that can be used up (if my memory is correct).
Each experiment so far basically said "we measured a small amount of thrust... so small that we're not sure if we measured any thrust at all."
The theory behind these devices says that thrust will increase by orders of magnitude if a superconducting RF cavity is used.
So why not do that? The results would be unambiguous, for a change.
That that is is that that that that is not is not.
I doubt both the studies but I am sure this will now attract enough eyeballs from many Physicists. I am sure we will soon hear more on this story. Stay tuned.