# NASA Paper Claims EM Drive Works. Newslink **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [November 21, 2016, 11:29pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695 "2016-11-21T23:29:19Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [November 22, 2016, 4:54pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/21 "2016-11-22T16:54:33Z")
Don’t think so but the paper states > [@](#): > > …magnetic interaction, which has the potential for a false positive resulting from dc currents in power cables interacting during test article operation with ambient magnetic fields (e.g., local Earth field, magnetic damper) to generate a torque displacement on the pendulum. All dc power cables are a twisted pair or twisted shielded pair to minimize magnetic interaction. The test article is tested in forward, reverse, and null thrust orientations, but dc power cable routing and orientation is the same for all three configurations (power cables come in from the top of the test article), meaning any false positives will be the same magnitude and polarity for all three tests. This is not observed during the test campaign. ---
**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\ **Post date:** [November 22, 2016, 5:18pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/22 "2016-11-22T17:18:49Z")
[Previous thread](http://boards.straightdope.com/sdmb/showthread.php?t=755463), which also references another previous thread. ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [November 22, 2016, 5:49pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/23 "2016-11-22T17:49:02Z")
> [@naita](#): > > This particular EM drive sends out nothing, and so, if it actually works, violates this fundamental law. But it emits energy, doesn’t it? Energy goes in; energy comes out. Or is the thrust detected simply a directional heat emission generated by the energy going in? ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [November 22, 2016, 5:57pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/24 "2016-11-22T17:57:32Z")
No, you wind up with waves reflecting back and forth inside the cavity and so you wind up with no net force. This EmDrive apparently does experience a push in a specific direction. Now you can argue one side of the drive is getting preferentially hotter and so emitting radiation and effectively acting like a infrared photon rocket. Apparently, that isn’t what’s happening here. I only skimmed the paper but my thoughts are it’s time for a number of groups to go forth and reproduce! ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [November 22, 2016, 6:01pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/25 "2016-11-22T18:01:08Z")
> [@naita](#): > > They haven’t been looking to explain anything yet. The first step was to “confirm” there was anything to explain, which they’ve done to the best of their ability within the very low budget. That’s what the paper looks like. > [@](#): > > And changing the shape of the chamber won’t make it not violate conservation of momentum. It might produce an effect that would explain what they see with shape used. What would happen if the shape were asymetrical? As pointed out before, now that there seems to be something to study we should see a flurry of research. ---
**Author:** ![Boyo\_Jim](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Boyo\_Jim](https://boards.straightdope.com/u/Boyo_Jim)\ **Post date:** [November 22, 2016, 6:40pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/26 "2016-11-22T18:40:58Z")
In the spirit of my recent prediction that the Democrat Party would sweep the Houses of Congress, let me share another about this. It is the first real world example of dark energy and it explains why the universe is accelerating outward. ---
**Author:** ![Half\_Man\_Half\_Wit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/half_man_half_wit/32/21766_2.png) [@Half\_Man\_Half\_Wit](https://boards.straightdope.com/u/Half_Man_Half_Wit)\ **Post date:** [November 22, 2016, 6:42pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/27 "2016-11-22T18:42:20Z")
Please note that something having passed peer review doesn’t mean that it’s right, nor that the referees, or even the authors, think it’s right. At best, they haven’t yet figured out any way to show how it’s wrong. (For instance, in my field, a paper was published that apparently demonstrated a device for faster-than-light communication; the referee was pretty certain that it was wrong, but at the time, nobody knew what didn’t fit. The resulting work led to the discovery of the no-cloning theorem, the fact that you can’t copy a single quantum system in an unknown state, which is nowadays one of the cornerstones of quantum information theory.) And while I haven’t yet read the paper (and am not an expert in the field regardless), just from the quotes in this thread, I kinda have to wonder how it ever got past peer review—the supposed ‘explanation’ is basically gobbledygook; quantum fluctuations are just a handy bookkeeping tool for certain calculations, and saying that you can ‘push off’ of them is basically like saying you’re pushing off of numbers. I certainly wouldn’t have accepted a paper with such a dodgy claim. But dodgy theory aside, if there’s an effect there, it’s certainly worth investigating. I’m reminded here of the Pioneer anomaly, which was an unexplained acceleration that the Pioneer spacecraft experienced that eventually turned out to be due to uneven thermal radiation. I don’t think this would be an effect strong enough to explain the acceleration in this case, but it’s certainly way too early to discount any mundane explanations of the effect—after all, the Pioneer anomaly also took a couple of years to resolve, and led to a lot of exotic speculation. > [@Quartz](#): > > But it emits energy, doesn’t it? Energy goes in; energy comes out. Or is the thrust detected simply a directional heat emission generated by the energy going in? You can’t really ‘emit energy’. Energy is a property of stuff, or of a collection of stuffs. If you move forward from a standstill, and nothing else ends up moving the other way, you’re violating conservation of momentum. ---
**Author:** ![Sage\_Rat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sage_rat/32/399_2.png) [@Sage\_Rat](https://boards.straightdope.com/u/Sage_Rat)\ **Post date:** [November 22, 2016, 9:54pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/28 "2016-11-22T21:54:56Z")
> [@usedtobe](#): > > I’m trying to think of a technology which defied accepted science and had to wait for the theory to catch up. The germ theory of disease. There was a doctor who did sufficient science to prove that if he and his nurses washed their hands, after working with the dead and ill, there was a lower mortality rate in the infant ward. All the other doctors decided that this was nonsense, since he had no theory about what was happening. > **[Ignaz Semmelweis](https://en.wikipedia.org/wiki/Ignaz_Semmelweis)** > > Ignaz Philipp Semmelweis (.mw-parser-output .IPA-label-small{font-size:85%}.mw-parser-output .references .IPA-label-small,.mw-parser-output .infobox .IPA-label-small,.mw-parser-output .navbox .IPA-label-small{font-size:100%}German: \[ˈɪɡnaːts ˈzɛml̩vaɪs\]; Hungarian: Semmelweis Ignác Fülöp \[ˈsɛmmɛlvɛjs ˈiɡnaːts ˈfyløp\]; 1 July 1818 – 13 August 1865) was a Hungarian physician and scientist of German descent, who was an early pioneer of antiseptic procedures, and was described as the "saviour of ... It should also be noted that Newton had no particular theory for gravity. He simply provided the formula and said, “Who cares why, it just is.” ---
**Author:** ![Llama\_Llogophile](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@Llama\_Llogophile](https://boards.straightdope.com/u/Llama_Llogophile)\ **Post date:** [November 22, 2016, 10:28pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/29 "2016-11-22T22:28:52Z")
> [@usedtobe](#): > > I’m trying to think of a technology which defied accepted science and had to wait for the theory to catch up. I seem to recall that the effectiveness of basic reaction rockets was seriously questioned before we succeeded in putting them in space. The idea was that in a vacuum they would not have anything to push against. Obviously, that was not correct. It would be cool if something similar happened here demonstrating that the concept does work, but I’m not holding my breath. ---
**Author:** ![Suburban\_Plankton](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/suburban_plankton/32/219_2.png) [@Suburban\_Plankton](https://boards.straightdope.com/u/Suburban_Plankton)\ **Post date:** [November 22, 2016, 11:07pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/30 "2016-11-22T23:07:26Z")
My understanding of the workings of the EM Drive is that microwaves are generated, then bounce around in a closed chamber, which somehow produces a measurable amount of thrust. The big “problem”, as I understand it, is that it does this “without requiring a fuel source”, which defies known laws of physics. But it seems to me that there is a “fuel source”…a craft powered by this engine either needs to carry some power source to generate the microwaves (call that “fuel”), or else it needs to obtain the power from some external source (say, the sun). In either case, we’re just ‘burning fuel’ to create thrust, just like in any other sort of engine, aren’t we? I assume I’m missing something here…but what? ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [November 22, 2016, 11:30pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/31 "2016-11-22T23:30:24Z")
> [@Llama\_Llogophile](#): > > I seem to recall that the effectiveness of basic reaction rockets was seriously questioned before we succeeded in putting them in space. The idea was that in a vacuum they would not have anything to push against. Surely you jest. ---
**Author:** ![Euphonious\_Polemic](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/euphonious_polemic/32/3002_2.png) [@Euphonious\_Polemic](https://boards.straightdope.com/u/Euphonious_Polemic)\ **Post date:** [November 22, 2016, 11:38pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/32 "2016-11-22T23:38:47Z")
> [@Llama\_Llogophile](#): > > I seem to recall that the effectiveness of basic reaction rockets was seriously questioned before we succeeded in putting them in space. The idea was that in a vacuum they would not have anything to push against. > > Obviously, that was not correct. It would be cool if something similar happened here demonstrating that the concept does work, but I’m not holding my breath. I’m pretty sure Newton’s third law was well understood by the entire scientific community before rockets made it to space. You may be recalling something that was said by non-scientists. ---
**Author:** ![Sage\_Rat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sage_rat/32/399_2.png) [@Sage\_Rat](https://boards.straightdope.com/u/Sage_Rat)\ **Post date:** [November 22, 2016, 11:58pm UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/33 "2016-11-22T23:58:26Z")
> [@Euphonious\_Polemic](#): > > I’m pretty sure Newton’s third law was well understood by the entire scientific community before rockets made it to space. You may be recalling something that was said by non-scientists. This. I’m not a physics expert by any means, but both Galileo and Newton were dealing with the behavior of objects in a vacuum well before the 20th century. By that time, the models were all already making the presumption of a vacuum as the default, with air resistance, etc. being a modifier to the system. ---
**Author:** ![Leaper](https://avatars.discourse-cdn.com/v4/letter/l/4bbf92/32.png) [@Leaper](https://boards.straightdope.com/u/Leaper)\ **Post date:** [November 23, 2016, 12:40am UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/34 "2016-11-23T00:40:25Z")
> [@Euphonious\_Polemic](#): > > I’m pretty sure Newton’s third law was well understood by the entire scientific community before rockets made it to space. You may be recalling something that was said by non-scientists. [Yes, it was.](http://www.popsci.com/military-aviation-amp-space/article/2009-07/new-york-times-nasa-youre-right-rockets-do-work-space) > [@New York Times editorial board](#): > > That Professor Goddard, with his ‘chair’ in Clark College and the countenancing of the Smithsonian Institution, does not know the relation of action to reaction, and of the need to have something better than a vacuum against which to react — to say that would be absurd. Of course he only seems to lack the knowledge ladled out daily in high schools. ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [November 23, 2016, 1:33am UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/35 "2016-11-23T01:33:06Z")
> [@Suburban\_Plankton](#): > > My understanding of the workings of the EM Drive is that microwaves are generated, then bounce around in a closed chamber, which somehow produces a measurable amount of thrust. The big “problem”, as I understand it, is that it does this “without requiring a fuel source”, which defies known laws of physics. > > But it seems to me that there is a “fuel source”…a craft powered by this engine either needs to carry some power source to generate the microwaves (call that “fuel”), or else it needs to obtain the power from some external source (say, the sun). In either case, we’re just ‘burning fuel’ to create thrust, just like in any other sort of engine, aren’t we? > I assume I’m missing something here…but what? Everything we design to move has to generate thrust. Sailboats generate thrust by deflecting the wind, cars by pushing against the ground with tires, rockets by pushing shit out behind them. With rockets, the mass and speed (momentum) of what goes out the back is approximately equivalent to the speed the rocket achieves in the other direction: conservation. Spacecraft have been tested with engines that create thrust by pushing ionized gas out the back, but conservation still applies. So, this thing seems to produce thrust simply by consuming energy to set up radiowave interference pattern inside the chamber. Nothing is coming out the back and there is nothing thrusting against something else to explain how the force is being created. This could be good because rockets need to haul around the matter they use to push themselves forward. This thing never pushes shit out the back, so the fuel mass would not have to be the large amount needed to complement the desired motion. If the power source were a TW nuclear reactor, the force could, theoretically, be respectable for a large craft without requiring an equivalent mass of reaction fuel. ---
**Author:** ![Declan](https://avatars.discourse-cdn.com/v4/letter/d/ecae2f/32.png) [@Declan](https://boards.straightdope.com/u/Declan)\ **Post date:** [November 23, 2016, 1:53am UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/36 "2016-11-23T01:53:29Z")
> [@eschereal](#): > > This could be good because rockets need to haul around the matter they use to push themselves forward. This thing never pushes shit out the back, so the fuel mass would not have to be the large amount needed to complement the desired motion. If the power source were a TW nuclear reactor, the force could, theoretically, be respectable for a large craft without requiring an equivalent mass of reaction fuel. At the moment, any ansewers would be guesses, but does this scale up or does it run into a mass wall at some point, ie like using an outboard motor to move a freighter. Second, what would the on ramp speed be for this drive, something like the plasma drive which takes a while to get up to speed, or a Jeremy Clarkson power on demand. Personal observation, if the drive works, it could open up the inner solar system. ---
**Author:** ![Sage\_Rat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sage_rat/32/399_2.png) [@Sage\_Rat](https://boards.straightdope.com/u/Sage_Rat)\ **Post date:** [November 23, 2016, 1:58am UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/37 "2016-11-23T01:58:37Z")
> [@eschereal](#): > > Everything we design to move has to generate thrust. Not entirely true. If I put a big hunk of steel on one side of a table and a super powerful electric magnet on the other, and hit the on switch, there will be no thrust moving the magnet toward the steel block. I could theorize (based on nothing whatsoever) that the EM device acts on a similar principal, using attraction to move itself, but somehow is able to shield itself from the attraction on one side, so that it is able to move any desired direction it wants. ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [November 23, 2016, 2:08am UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/38 "2016-11-23T02:08:26Z")
The paper that **Grey** linked to above presents a possible QM explanation as to what is happening, > [@](#): > > … the supporting physics model used to derive a force based on operating conditions in the test article can be categorized as a nonlocal hidden-variable theory, or pilot-wave theory for short. Pilot-wave theories are a family of realist interpretations of quantum mechanics that conjecture that the statistical nature of the formalism of quantum mechanics is due to an ignorance of an underlying more fundamental real dynamics, and that microscopic particles follow real trajectories over time just like larger classical bodies do…A family of models categorized as vacuum-based pilot-wave theories or stochastic electrodynamics (SED) … explored the concept that the electromagnetic vacuum fluctuations of the zero point field represent a natural source of stochasticity in the subquantum realm and provide classical explanations for the origin of the Planck constant, Casimir effect, ground state of hydrogen, and much more… > > Although the idea of a pilot wave or realist interpretation of quantum mechanics is not the dominant view of physics today (which favors the Copenhagen interpretation), it has seen a strong resurgence of interest over the last decade based on some experimental work pioneered by Couder and Fort (who) discovered that bouncing a millimeter-sized droplet on a vibrating shallow fluid bath at just the right resonance frequency created a scenario where the bouncing droplet created a wave pattern on the shallow bath that also seemed to guide the droplet along its way… in subsequent testing … this macroscopic classical system was able to exhibit characteristics thought to be restricted to the quantum realm. To date, this hydrodynamic pilot-wave analog system has been able to duplicate the double slit experiment findings, tunneling, quantized orbits, and numerous other quantum phenomena… > > In addition to these quantum analogs, there may already be direct evidence supportive of the pilot-wave approach: specifically, Bohmian trajectories may have been observed by two separate experiments working with photons. Reconsidering the double slit experiment with the pilot-wave view, the photon goes through one slit, and the pilot wave goes through both slits. The resultant trajectories that photons follow are continuous real trajectories that are affected by the pilot wave’s probabilistic interference pattern with itself as it undergoes constructive and destructive interference due to reflections from the slits. > > In the approach used in the quantum vacuum plasma thruster (also known as a Q thruster) supporting physics models, the zero point field (ZPF) plays the role of the guiding wave in a similar manner to the vacuum-based pilot-wave theories… If a medium is capable of supporting acoustic oscillations, this means that the internal constituents were capable of interacting and exchanging momentum. > > If the vacuum is indeed mutable and degradable as was explored, then **it might be possible to do/extract work on/from the vacuum, and thereby be possible to push off of the quantum vacuum and preserve the laws of conservation of energy and conservation of momentum**. It is proposed that the tapered RF test article pushes off of quantum vacuum fluctuations, and the thruster generates a volumetric body force and moves in one direction while a wake is established in the quantum vacuum that moves in the other direction. (_emphasis mine_) I greatly abbreviated the content. It is from section **10. Discussion** , about 9/10[sup]th[/sup]s of the way down the page. Fascinating stuff. ---
**Author:** ![Llama\_Llogophile](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@Llama\_Llogophile](https://boards.straightdope.com/u/Llama_Llogophile)\ **Post date:** [November 23, 2016, 2:11am UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/39 "2016-11-23T02:11:04Z")
> [@Euphonious\_Polemic](#): > > I’m pretty sure Newton’s third law was well understood by the entire scientific community before rockets made it to space. You may be recalling something that was said by non-scientists. I can’t remember where I read this - I’m a space history geek, so I’ve read a lot of that stuff. I’ll post it when it comes to me. ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [November 23, 2016, 2:13am UTC](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695/40 "2016-11-23T02:13:26Z")
> [@Sage\_Rat](#): > > Not entirely true. If I put a big hunk of steel on one side of a table and a super powerful electric magnet on the other, and hit the on switch, there will be no thrust moving the magnet toward the steel block. But if you put both the magnet and the block of steel on an operating air hockey table (frictionless surface), the two will be drawn together, to a barycenter (point closer to the heavier mass). To move the block all the way across the table, the electromagnet must have a counterforce (it is effecting thrust against whatever it is mounted on). [Previous page](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695.md?page=1) [Next page](https://boards.straightdope.com/t/nasa-paper-claims-em-drive-works-newslink/772695.md?page=3)