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EmDrive: NASA Eagleworks' Peer-Reviwed Paper Is On Its Way (ibtimes.co.uk) 532

An anonymous reader quotes a report from International Business Times UK: An independent scientist has confirmed that the paper by scientists at the NASA Eagleworks Laboratories on achieving thrust using highly controversial space propulsion technology EmDrive has passed peer review, and will soon be published by the American Institute of Aeronautics and Astronautics (AIAA). Dr Jose Rodal posted on the NASA Spaceflight forum -- in a now-deleted comment -- that the new paper will be entitled "Measurement of Impulsive Thrust from a Closed Radio Frequency Cavity in Vacuum" and is authored by "Harold White, Paul March, Lawrence, Vera, Sylvester, Brady and Bailey." Rodal also revealed that the paper will be published in the AIAA Journal of Propulsion and Power, a prominent journal published by the AIAA, which is one of the world's largest technical societies dedicated to aerospace innovations. Although Eagleworks engineer Paul March has posted several updates on the ongoing research to the NASA Spaceflight forum showing that repeated tests conducted on the EmDrive in a vacuum successfully yielded thrust results that could not be explained by external interference, those in the international scientific community who doubt the feasibility of the technology have long believed real results of thrust by Eagleworks would never see the light of day.
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EmDrive: NASA Eagleworks' Peer-Reviwed Paper Is On Its Way

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  • Prepare to be (Score:2, Insightful)

    by Maritz ( 1829006 )
    Underwhelmed.
    • by Z80a ( 971949 )

      But if confirmed, expect a flood stories on how "it will allow us to have true hoverboards in 10 years!".

    • by XXongo ( 3986865 )

      Underwhelmed.

      I'll be interested in seeing the results. So far, each release of test results has falsified all the previous work, but with the conclusion "well, even though we didn't replicate previous results, there's still a little bit left that we can't explain."

      • Re:Prepare to be (Score:4, Informative)

        by Maritz ( 1829006 ) on Wednesday August 31, 2016 @08:28AM (#52802165)
        For me, even when there seemed to be some effect, it was simply far, far too small. Well within experimental noise - and certainly nothing you're going to propel anything anywhere with.
        • Re:Prepare to be (Score:5, Informative)

          by meta-monkey ( 321000 ) on Wednesday August 31, 2016 @08:39AM (#52802241) Journal

          Well within experimental noise - and certainly nothing you're going to propel anything anywhere with.

          I agree I'm still far from sold on the EM drive. I want to see it working in a vacuum, away from earth's magnetic field, and I want an explanation for the physics behind it. But if there's new physics, then who can say what the eventual application will be? Our first experiments with radioactive materials made things a little warm and glowy (and poisonous) but then fast forward a few decades and we've got mushroom clouds and nuclear reactors.

          • by Maritz ( 1829006 )
            If there are new physics here I'll be as happy as pretty much anyone. But yeah, we're a long way from that with EM Drive and I very much doubt we'll ever get there. This is kinda like another E-Cat for me, but without the grubby little con-man.
            • Re:Prepare to be (Score:5, Insightful)

              by JoeMerchant ( 803320 ) on Wednesday August 31, 2016 @11:24AM (#52803241)

              It's also possible that there are no new physics here, just an example of a misunderstood corner case of existing physics...

              Build it, test it, see what happens. Until it's proven (and I mean really proven, not just dismissed) false, it would seem to be worth the research investment.

          • by sycodon ( 149926 )

            If they verify an observable thrust, then it is a Big Deal because that IS New Physics.

        • For me, even when there seemed to be some effect, it was simply far, far too small. Well within experimental noise - and certainly nothing you're going to propel anything anywhere with.

          Yep. When part of their original paper stated "our test set up was so sensitive we could see noise due to waves in Galveston Bay twenty miles away!", my reaction was "omigod, that's a very bad thing," rather than the "wow, they made a great sensor" reaction I think they were looking for.

        • Even an infinitesimal propulsion could get a micro-probe up to near light speed if it could be generated for free. Unfortunately, that remains about as likely as the odds of that SETI signal being aliens.

          • Even an infinitesimal propulsion could get a micro-probe up to near light speed ...

            It could probably get anything up to near light speed given enough time... And keeping a micro-probe from getting destroyed by a particle of dust, while moving at near light speed, is whole other problem.

    • I am but secretly a little bit of me is clinging to the hope that this isn't Cold Fusion again
  • Author List (Score:4, Funny)

    by PvtVoid ( 1252388 ) on Wednesday August 31, 2016 @08:04AM (#52802025)

    Who are "Lawrence, Vera, Sylvester, Brady and Bailey"? Their cats?

    • It's the long list of co-authors who get abbreviated mention, who may or may not have written but probably worked on the project and proof-read the paper. If not feline, then I agree it's odd there aren't first-name initials, too. It was "Sylvester" that clued you in, right?
      • by plopez ( 54068 )

        In fact they sound like first names. Very unprofessional.

        • Right. In our lab, simple professionalism prevents us from bringing on faculty or staff whose surnames could be mistaken for given names. Those pesky Aussie gits Marshall [wikipedia.org] and Warren [wikipedia.org] have never gotten over the rejection.

  • Peer reviw (Score:5, Funny)

    by Buchenskjoll ( 762354 ) on Wednesday August 31, 2016 @08:07AM (#52802041)
    Reviw is sooooo important....
  • How does the energy efficiency of this drive compare to a normal rocket? Could this allow interstellar travel, by humans, within a normal human lifespan? What kind of reletavistic effects happen at high speed? I would assume thrust would drop as you approach C.
    • by Geoffrey.landis ( 926948 ) on Wednesday August 31, 2016 @08:18AM (#52802099) Homepage

      How does the energy efficiency of this drive compare to a normal rocket?

      If it works as advertised, it violates the law of conservation of energy, so its energy efficiency can be infinite.

      (it produces a force with no reaction mass. Since energy is 1/2 mV^2, power is force times velocity, and thus the change in energy (per unit time) is proportional to velocity. So, if it runs at a given power level to produce a given thrust level, you can get more energy out than you put in simply be starting out in motion.)

      Could this allow interstellar travel, by humans, within a normal human lifespan? What kind of reletavistic effects happen at high speed? I would assume thrust would drop as you approach C.

      Well, if it violates the theory of relativity, anything could happen, I guess. Right now the thrust level quoted is micronewtons, so it would take millions of years to get up to the speed of light. But if the machine works, even at all, all bets on physics are off.

      • Re: (Score:3, Interesting)

        by minogully ( 1855264 )

        Well, if it violates the theory of relativity, anything could happen, I guess.

        The guy ("scientist"?), Roger Shawyer, who invented it claims that it's actually due to the theory of relativity that it works. Here's a quote from the article:

        based on the theory of special relativity, electricity converted into microwaves and fired within a closed cone-shaped cavity causes the microwave particles to exert more force on the flat surface at the large end of the cone (i.e. there is less combined particle momentum at the narrow end due to a reduction in group particle velocity), thereby generating thrust.

        I'm not a physicist, so I can't speak to whether his explanation makes sense.

        • by XXongo ( 3986865 ) on Wednesday August 31, 2016 @08:47AM (#52802273) Homepage

          Well, if it violates the theory of relativity, anything could happen, I guess.

          The guy ("scientist"?), Roger Shawyer, who invented it claims that it's actually due to the theory of relativity that it works.

          Yes, but their test results explicitly falsified that theory. They tested this. The device (was claimed to) produce thrust whether or not it had the asymmetry that Shawyer claimed was required by his theory

          ...I'm not a physicist, so I can't speak to whether his explanation makes sense.

          I am a physicist. His explanation makes no sense.

        • I'm not a physicist, so I can't speak to whether his explanation makes sense.

          It doesn't. Firstly, Noether's theorem applies to relativity and proves that conservation of momentum happens in relativity. So, it's impossible for this device to work merely using the theory of relativity. There was an error in his maths and I think someone actually found it.

      • by Anonymous Coward

        They found a way to hit the rounding error in the universe simulation and accumulate it over time

      • by Anonymous Coward

        First of all, we already know that most of Newtonian physics is wrong and we've known this for over 100 years. Take gravity for example - Newton's limited understanding of physics has no explanation for it, but general relatively tells us that mass distorts spacetime which results in an attraction between two bodies. Anyway, a more relevant example is the fact that the universe is not only expanding, but it's expanding faster than the speed of light and it's accelerating. A limited understand of special

      • If it works as advertised, it violates the law of conservation of energy, so its energy efficiency can be infinite.
        (it produces a force with no reaction mass.

        OK, I'm not a physicist and it's been a long time since my physics classes, but I don't see why mass is important at all. Mass and energy are interchangeable by E=mc^2. Electric motors produce motion without losing any mass, so I don't really see why it's impossible for there to be some way of producing thrust in a vacuum using only energy. Just bec

        • If it works as advertised,...it produces a force with no reaction mass.

          OK, I'm not a physicist and it's been a long time since my physics classes, but I don't see why mass is important at all. Mass and energy are interchangeable by E=mc^2. Electric motors produce motion without losing any mass,

          Well, to product thrust, they have to push on something.

          so I don't really see why it's impossible for there to be some way of producing thrust in a vacuum using only energy. Just because all our prior methods of producing thrust in space depend on Newton's 3rd law doesn't mean that it has to be that way. While there may be no mass escaping from this device, it absolutely is consuming energy. Where does that go? We already know we can produce thrust with lasers, which are pure energy; we've even talked about making micro-miniature space probes and sending them to Alpha Centauri with a big laser, and the whole principle of solar sails rests on thrust provided by pure energy.

          If it released energy out one side, that counts as reaction mass. They would get thrust according to Einstein's relation: momentum = E/c
          But, as claimed, the device produces thrust by just bounding energy around inside a cavity-- they claim that it is not simply the photon force.

      • I wonder if this thing is more efficient than radiating the same amount of microwaves or laser light out the back of a rocket. That is does it derive thrust resonantly with no loss of photons (other than imperfections) or is it a trade of one photon for one photons worth of impulse (same as a laser thruster).

        And I also wonder how they cooled this thing. if it was in a vaccuum and power goes in then it heats up. It would heat up indefinitely if it did not radiate somehow. Perhaps the radiation isn't isot

        • The reports are that it's far more efficient than a straight EM drive. Photons make really inefficient reaction mass, since the amount of momentum change you get per unit energy is very, very low. Assuming that the reported thrust is accurate, it means that the drive is reacting against some external matter.

    • by Erik Hensema ( 12898 ) on Wednesday August 31, 2016 @08:25AM (#52802141) Homepage
      The efficiency is very low. Read TFA: "[...] the system is consistently performing with a thrust to power ratio of 1.2 +/- 0.1 mN/Kw ()".

      According to TFA, however, they are working on a far more efficient design.
    • by joh ( 27088 ) on Wednesday August 31, 2016 @08:30AM (#52802187)

      The trouble is that the thrust is so low that measuring it reliably is so hard that nobody knows if there is thrust at all or just measurement problems. It's said to be about 1mN/kW, much lower than even an ion drive.

      I think there is just noise and no signal and people are seeing a rabbit in the clouds because they're looking for it very hard.

      • I think people don't really get the difference in scale between 1mn and 1kw, so why having the two together makes things so hard.

        1mn is of course the weight exerted by 0.1g. That's about half a grain of rice. To get that, you require 1kw. Think about the things that take pr process 1kw of power, e.g. an electric bar fire, a very high end PC, a mid-size UPS and so on and so forth.

        They're all large, heavy things, which require considerable cooling to dump that much heat.

        So the question is how do you transport

      • I'd love to see this be a real effect, but it just sounds like cold fusion, or polywater, or homeopathy -- a tiny effect, where the more closely you examine it, the harder it becomes to see.

        Then again, high-temperature superconductors looked the same way for a bit, and they have worked out quite nicely, with theory trying desperately to regain its footing as it's dragged along behind practice.

        And as for fishing small signals out of large backgrounds, yes, that makes things tricky, but my working GPS receive

        • Even if it is a real effect, I can't see a real use for it. For instance, someone said in another comment something to the effect that satellites could use it to maintain their orbits... except that the amount of thrust I see being mentioned likely wouldn't overcome atmospheric drag or solar wind. However, it is science worth exploring. Either the thrust is eventually found to be some unaccounted for noise, or we eventually figure out the science behind it. If it's real, the new ideas could be expanded to
    • Its massively inefficient. Its probably the least efficient use of electricity ever invented actually. It works without a fuel tank though. People are only really excited about its potential for space travel because of that. See, if it works entirely on solid-state electronics, without needing fuel reserves, then in theory you can power this from outer space forever just on solar radiation. Up until now, all other rocket technology was limited in range by the physical weight of its own fuel.

    • How does the energy efficiency of this drive compare to a normal rocket?

      Utter crap. But what it would give (assuming it works) is freedom from having to carry reaction mass.

      But if it works, then it's going to open a whole new world in physics that hasn't been considered up until now - and it's likely to be obsolete within a few years once a theory that explains it comes to light.

      (I'm betting on measurement error but hoping for something much more exciting)

      Could this allow interstellar travel, by humans, wit

  • On its way (Score:5, Funny)

    by wonkey_monkey ( 2592601 ) on Wednesday August 31, 2016 @08:09AM (#52802047) Homepage

    EmDrive: NASA Eagleworks' Peer-Reviwed Paper Is On Its Way

    But we're not sure how long it'll take because we're not sure it puts out any thrust.

    • Well, it's as the old saying goes, "To put any trust in it, you gotta get thrust out of it."

    • Re: (Score:3, Interesting)

      by Bruce Perens ( 3872 )

      Yes, but given the number of folks who set out to disprove and ended up with thrust they can't explain, we're far from ready to say "no".

      If you live in a Newtonian world, you're not going to accept that this could ever work. If you admit to the possibility that momentum could be quantized, you can't rule it out yet.

  • Well... (Score:4, Interesting)

    by John Smith ( 4340437 ) on Wednesday August 31, 2016 @08:28AM (#52802173)
    I imagine that there will be replicability tests. It's possible, but not certain, that we may have found Clarke's "space drive", a drive requiring no reaction mass. On the other hand, so many of these things have fizzled, I'm remaining VERY cautiously optimistic.
    • Re:Well... (Score:5, Insightful)

      by NoNeeeed ( 157503 ) <slash@@@paulleader...co...uk> on Wednesday August 31, 2016 @08:43AM (#52802257)

      Likewise. I'm hopefully sceptical :)

      At worst there is an interesting effect going on that is worth further study and might provide some new insights into some aspects of physics, or simply improvements to experimental techniques. At best it has the possibility to revolutionise some aspects of space exploration.

      I am sceptical that this will live up to the best case, but I really hope that my scepticism turns out to be wrong.

      This is what science is all about. There's an odd effect, people are doing experiments, whatever happens we will have learnt something which may one day be useful. This is an extraordinary claim, it requires extraordinary proof, which we will hopefully get.

    • Re: (Score:2, Insightful)

      by Anonymous Coward
      Caution with a little optimism is good. What we must not do is to say that does not work just because it goes against someone dogmas (I doubt the haters here have the technical capability to do the tests and especially the impartiality necessary to analyze the results). I for myself say that at least is something really interesting going on that should be investigated further.
    • There's really no reason for any optimism. No advanced propulsion ever has or ever will be invented by accident by a random guy whose own theory for how his magic box works was self-falsified. The process of finding out where the tiny measurement error comes from may be scientifically interesting and may result in more peer reviewed papers, but there's no chance it's going to make the magic trick real.

      • Re: (Score:2, Insightful)

        by Anonymous Coward

        > No advanced propulsion ever has or ever will be invented by accident by a random guy ....

        And there, folks, is a fine example of a completely unscientific statement :)

  • Seriously? (Score:5, Funny)

    by CCarrot ( 1562079 ) on Wednesday August 31, 2016 @08:57AM (#52802323)

    EmDrive: NASA Eagleworks' Peer-Reviwed Paper Is On Its Way

    Ow ow ow, I think they just broke my irony meter!

    • EmDrive: NASA Eagleworks' Peer-Reviwed Paper Is On Its Way

      Ow ow ow, I think they just broke my irony meter!

      No mod points today, so I just chimed in to say - Hell, yeah! How has nobody else commented on this!?

  • Notice they always shove "NASA" in there as if it lends it any credibility. The truth is that anyone can rent "NASA" lab facilities. This is just another hoax. Also, it "soon will be published" in AIAA. Uh huh. Sure it will.
    • Notice they always shove "NASA" in there as if it lends it any credibility. The truth is that anyone can rent "NASA" lab facilities. This is just another hoax. Also, it "soon will be published" in AIAA. Uh huh. Sure it will.

      Even if it were from NASA, that wouldn't be a massive credibility boost. NASA, like many other great places, has amazing people and meh people.

      The question is the science.

      • 100% correct. But you will notice they alway shove "NASA" in there anyway. It has all the hallmarks of a hoax.
  • by backwardsposter ( 2034404 ) on Wednesday August 31, 2016 @09:19AM (#52802453)

    If you want to do some armchair physics, these forums are really interesting. https://forum.nasaspaceflight.... [nasaspaceflight.com]

    People are attempting to recreate the "thrust-less" momentum at home basically. Lots of skepticism, lots of optimism, but real numbers being thrown around.

    We're almost past the point of whether or not it works and moving onto why it works.

Never test for an error condition you don't know how to handle. -- Steinbach

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