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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."

62 of 518 comments (clear)

  1. Looking more and more likely all the time... by moosehooey · · Score: 3, Interesting

    Maybe this will be one that turns out not to be a scam...

    1. Re: Looking more and more likely all the time... by silentcoder · · Score: 4, Informative

      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 *
    2. Re: Looking more and more likely all the time... by Megol · · Score: 5, Insightful

      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 :)

    3. Re: Looking more and more likely all the time... by alvinrod · · Score: 5, Interesting

      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.

    4. Re: Looking more and more likely all the time... by garyisabusyguy · · Score: 3, Funny

      It's because we are tired from telling all them damn kids at reddit to get offa our lawn

      --
      Wherever You Go, There You Are
    5. Re: Looking more and more likely all the time... by roca · · Score: 4, Informative

      Neither Newton's nor Einstein's theory of gravitation were greeted with "extreme skepticism" by the general community.

    6. Re: Looking more and more likely all the time... by cbhacking · · Score: 3, Interesting

      Yep, the microwave cavity is sealed. Nowhere for them to go.

      Also, even in these early and probably very inefficient (assuming the thing really works) trials, the thrust/power ratio is something like three orders of magnitude beyond what you'd get from a photon drive. No "microwave-emitting thruster" operating at these power levels would come even close to the sensitivity threshold of the experimental apparatus, much less reach several times that threshold.

      --
      There's no place I could be, since I've found Serenity...
    7. Re: Looking more and more likely all the time... by ericloewe · · Score: 5, Informative

      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.

    8. Re: Looking more and more likely all the time... by ericloewe · · Score: 4, Informative

      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.

    9. Re: Looking more and more likely all the time... by sjames · · Score: 3, Informative

      Not necessarily. Leading WAGs include that it is thrusting against dark matter or space itself. In those scenarios, momentum is still conserved.

    10. Re: Looking more and more likely all the time... by Dunbal · · Score: 5, Insightful

      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.
    11. Re: Looking more and more likely all the time... by Sique · · Score: 5, Informative

      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.

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      .sig: Sique *sigh*
    12. Re: Looking more and more likely all the time... by Michael+Woodhams · · Score: 5, Informative

      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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    13. Re: Looking more and more likely all the time... by tnk1 · · Score: 3, Insightful

      The crowd is skeptical because we're being told by everyone, including the researchers, that this should be scrutinized closely because while this might be entirely new science, that is a very high bar to jump over for a reason.

      Humanity clearly doesn't know everything about physics, but we know enough that we've done some fairly amazing practical things with it. Recent scientists are not banging rocks together to get sparks, or even walking around poking radium in 19th Century dresses. That means we pretty much know where we think we need to look for new science, and until recently, this was not one of those places.

      So yes, being skeptical is a good idea here, although dismissing it outright seems to be unwarranted at the moment.

    14. Re: Looking more and more likely all the time... by serviscope_minor · · Score: 3

      How are we to know which of our theories are accurate?

      You should read "the relativity of wrong". It explains this stuff well.

      Newton's law is never going to be disproved, ever. It's been extended with relativity and will probably be extended again. It is never going to be proven wrong because it produces exceptionally accurate predictions is everything you personally can see (pretty much provided you're not a physicist or astronomer).

      In order to be disproven, it will have to stop making accurate predictions.

      --
      SJW n. One who posts facts.
    15. Re: Looking more and more likely all the time... by localman · · Score: 3, Informative

      > Modern physics is never incorrect.

      And you, sir, have just turned science into religion.

      The whole reason science is superior to religion is that it openly admits that it may be incorrect, and allows for itself to be corrected. It is, as you correctly outline, an iterative process that approaches truth over time. But part of that process is accepting that any truth may be overturned by new evidence. And while Einstein didn't "disprove" Newton, he did show flaws in the theory which meant that it was, in a very small way, wrong. And that's fine. Claiming it was "extended" and not "wrong" is playing semantics and makes you sound like a religious apologist.

      The more comfortable we are with being wrong, and the process of refinement, the better scientists we are. The more we claim that some aspect of science is "never incorrect", the more dogmatic we are and the science suffers.

      The predictions of modern physics are phenomenally accurate in many domains. But we haven't run tests in nearly enough domains to claim perfection yet. And we've no need to be defensive about it. Science is the only way to the next truth, and that's good enough for me.

    16. Re: Looking more and more likely all the time... by localman · · Score: 3, Insightful

      > Because they predict things up to the level of accuracy that we can currently measure, within the very limited energy and size domains we have access to. That's all there is to it.

      Fixed that for you.

      When you can predict particle behavior inside a black hole with planck-length precision, or you can model gravity at the galactic scale without relying on unobserved "dark matter", I might be as confident as you that our current understanding is rock solid.

    17. Re: Looking more and more likely all the time... by delt0r · · Score: 3, Insightful

      That is because they both explained previous results they already had. While this new thing violates 400 years of experiments and results.

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    18. Re: Looking more and more likely all the time... by delt0r · · Score: 3, Informative

      Oh i read them. The NASA ones. And quite frankly they are shit. And rightly didn't get properly published.

      You do know that a reactionless drive means not only that momentum is not conserved. But that the laws of physics are different in different places. Also that energy is not conserved. A reactionless drive is always a over unity device. Or are you just batting for your beloved germans. Perhaps if this was done properly i would take them more seriously. But a magazine and a talk (not peer reviewed) don't count.

      Also you really don't know your physics all that well.

      --
      If information wants to be free, why does my internet connection cost so much?
    19. Re: Looking more and more likely all the time... by nine-times · · Score: 4, Insightful

      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.

  2. Excellent news! by areusche · · Score: 5, Insightful

    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!

  3. Fuel Efficiency? by pwnyxpress · · Score: 3, Funny

    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.

  4. Not quite. by mbone · · Score: 4, Informative

    "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."

    What more do I need to say?

    1. Re:Not quite. by Namarrgon · · Score: 4, Informative

      How about the very next sentence?

      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.

      --
      Why would anyone engrave "Elbereth"?
  5. Re:Blimey by Anonymous Coward · · Score: 5, Insightful

    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.

  6. Re:I'll wait until by Archfeld · · Score: 4, Insightful

    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.

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    errr....umm...*whooosh* *whoosh* Is this thing on ?
  7. Believe it when I see it by meta-monkey · · Score: 5, Informative

    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.
    1. Re:Believe it when I see it by meta-monkey · · Score: 4, Insightful

      Skeptical != cynical.

      --
      We don't have a state-run media we have a media-run state.
  8. From the published paper... by Anonymous Coward · · Score: 5, Informative

    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.

  9. Re:extracting "fuel" from the very fabric of space by ihtoit · · Score: 5, Informative

    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
  10. Re:I'll wait until by PopeRatzo · · Score: 3, Insightful

    Until Mythbusters confirms it, I'll just say it's Plausible.

    Mythbusters' pop skepticism is the very definition of junk science.

    If you're waiting for confirmation from Penn Jillette or some other aging magician or Skeptical Inquirer, you missed out on a successful career as an economist.

    --
    You are welcome on my lawn.
  11. ah, Tajmar eh? by rubycodez · · Score: 4, Informative

    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.

  12. Re:Blimey by TWX · · Score: 5, Informative

    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.
  13. Can't this be tested on a Cube Sat? by mykepredko · · Score: 4, Interesting

    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.

  14. Re:Why the controversy? by CrimsonAvenger · · Score: 3, Informative

    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.

    Note, for the record, that an ion thruster IS a rocket - it shoots mass out the back (ions, in this case, accelerated electricly) just like any other rocket.

    Note that if this EM drive pushes photons out the back, it is also a rocket. However, what I've read on the subject says it doesn't push photons out the back (not even microwave photons), so it's either something unexpected, or a huge steaming pile.

    I'll be interested in the first deep-space probe built to test this thing. Should be simple enough - solar panels for power, EM-Drive for push, a comm-channel or six, and something to announce its presence, so we can determine its velocity relative to Earth at all times. If it accelerates, we win. If not, we wasted the cost of a (small) satellite....

    --

    "I do not agree with what you say, but I will defend to the death your right to say it"
  15. Re:Blimey by Anonymous Coward · · Score: 3, Informative

    Of course they do. Ions are simply an atom that has either gained or lost electrons and now has a net electric charge, either (+) or (-). As such, they are made up of protons, neutrons and electrons, all of which have mass.

  16. Re:Blimey by SuricouRaven · · Score: 4, Informative

    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.

  17. Re:Blimey by sosume · · Score: 4, Funny

    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.

  18. Re:Blimey by Guspaz · · Score: 4, Insightful

    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.

  19. Physics time! by cbhacking · · Score: 5, Interesting

    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...
    1. Re:Physics time! by cbhacking · · Score: 4, Insightful

      A) That's one hypothesis among several, and many physicists claim it is, to use your term, "bollocks". I did mention there are multiple theories about how it works. They all have supporters, but they all have counterarguments too.

      B) No, classical rocket engines push real particles one way and itself the other way. Unless you intend to claim that "virtual" and "real" particles are the same thing, it's not working "exactly the same way". Analogously, perhaps, but hardly "exactly the same".

      Oh, and just for the heck of it:
      C) To conclusively state that the EM Drive works according to your preferred theory is quite absurd unless you're an extremely well-educated theoretical physicist, and only slightly less even then. To even *claim* that I claimed anything about how the drive works, much less that my supposed idea is "bollocks", indicates a lack of reading comprehension, lack of understanding of the concept of scientific hypotheses, and lack of maturity.

      Good day to you.

      --
      There's no place I could be, since I've found Serenity...
    2. Re:Physics time! by cbhacking · · Score: 4, Informative

      Except it doesn't. The microwaves are not emitted anywhere. They are generated into a sealed chamber. There's nowhere they can go.

      The formulae you listed would be useful to describe thrust from a photon drive (or light drive), but those need an open-ended emitter. Also, the results you get from them are about three orders of magnitude too low for the observed ratio of thrust to power. A 700W microwave photon drive wouldn't be detectable by the experimental apparatus.

      --
      There's no place I could be, since I've found Serenity...
  20. Re:Blimey by meerling · · Score: 4, Informative

    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.

  21. Full Text + links from Hacked.com by cbhacking · · Score: 5, Informative

    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."

    “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," 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...
  22. Re:Blimey by danceswithtrees · · Score: 4, Informative

    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).

  23. Re:Blimey by Applehu+Akbar · · Score: 4, Interesting

    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?

  24. Physics time! You misunderstand ion drives by cbhacking · · Score: 3, Informative

    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...
  25. The /. title is bullshit by DrJimbo · · Score: 5, Informative

    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
  26. Ooh Oopsie by Greyfox · · Score: 4, Funny

    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?

  27. Re:Blimey by ebrandsberg · · Score: 5, Insightful

    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.

  28. Re:Just test it in space already by Greyfox · · Score: 3, Funny

    Oh sure! And 100,000 years later when a cubesat travelling .9999 the speed of light plows into the Dynarri ambassador's starship, guess who they'll be coming for!

    --

    I'm trying to teach myself to set people on fire with my mind... Is it hot in here?

  29. Re:Blimey by ZankerH · · Score: 4, Funny

    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?

  30. Re:Blimey by ganv · · Score: 5, Insightful

    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.

  31. Compare to the Higgs boson by Michael+Woodhams · · Score: 5, Informative

    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.
  32. The Dean Drive is back by Antique+Geekmeister · · Score: 3, Informative

    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.

  33. Yeah for EM Drive! by drwho · · Score: 4, Insightful

    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

  34. Re:Blimey by lgw · · Score: 4, Insightful

    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.

    --
    Socialism: a lie told by totalitarians and believed by fools.
  35. Re:Blimey by Mateorabi · · Score: 4, Interesting

    "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

  36. Re:Blimey by HornWumpus · · Score: 4, Informative

    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.

    --
    John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
  37. Some clarifiications by gnaarly · · Score: 3, Informative

    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.

  38. Re:Blimey by Scottingham · · Score: 4, Insightful

    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.

  39. Stop calling it "NASA's" by NicknameUnavailable · · Score: 3, Insightful

    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.