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NASA Science

NASA Engineer's 'Helical Engine' May Violate Laws of Physics (newscientist.com) 150

NASA engineer David Burns posted a paper describing the concept of his "helical engine," which could take humans to the stars by exploiting mass-altering effects known to occur at near-light speed. Unfortunately, it's been met with skepticism from those who say it violates the conservation of momentum, a core physical law. New Scientist explains: To get to grips with the principle of Burns's engine, picture a box on a frictionless surface. Inside that box is a rod, along which a ring can slide. If a spring inside the box gives the ring a push, the ring will slide along the rod one way while the box will recoil in the other. When the ring reaches the end of the box, it will bounce backwards, and the box's recoil direction will switch too. This is action-reaction -- also known as Newton's third law of motion -- and in normal circumstances, it restricts the box to wiggling back and forth. But, Burns asks, what if the ring's mass is much greater when it slides in one direction than the other? Then it would give the box a greater kick at one end than the other. Action would exceed reaction and the box would accelerate forwards.

Martin Tajmar at the Dresden University of Technology in Germany, who has performed tests on the EM Drive, believes the helical engine will probably suffer the same problem. "All inertial propulsion systems -- to my knowledge -- never worked in a friction-free environment," he says. This machine makes use of special relativity, unlike the others, which complicates the picture, he says, but "unfortunately there is always action-reaction." Burns has worked on his design in private, without any sponsorship from NASA, and he admits his concept is massively inefficient. However, he says there is potential to harvest much of the energy that the accelerator loses in heat and radiation. He also suggests ways that momentum could be conserved, such as in the spin of the accelerated ions.
"I know that it risks being right up there with the EM drive and cold fusion," he says. "But you have to be prepared to be embarrassed. It is very difficult to invent something that is new under the sun and actually works."
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NASA Engineer's 'Helical Engine' May Violate Laws of Physics

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  • Obligatory (Score:5, Funny)

    by Falconhell ( 1289630 ) on Tuesday October 15, 2019 @02:02AM (#59308298) Journal
  • It's a Dean Drive (Score:5, Interesting)

    by Antique Geekmeister ( 740220 ) on Tuesday October 15, 2019 @02:14AM (#59308308)

    See https://en.wikipedia.org/wiki/... [wikipedia.org] . John Campbell, the editor of Analog science fiction and science fact, was a strong proponent of the Dean drive, which never did work if hung on a pendulum to eliminate rhythmic friction with the surface it rested on.

    • by Viol8 ( 599362 ) on Tuesday October 15, 2019 @06:20AM (#59308644) Homepage

      .. the physics they use would also apply to nature in general and if that were the case then the universe would long ago have filled up with all the extra energy generated out of nowhere by asymmetric particle interactions.

      Or maybe thats what dark energy is. Who knows!

      • by aquabat ( 724032 )
        +1 for having an on-point username.
      • Who knows!

        The key words here... despite all the warm, stinky air emanating from the orifices of these far-too-sure-of-their-theorums Armchair Aspies.

      • Why do you think there's more matter than antimatter?

      • .. the physics they use would also apply to nature in general and if that were the case then the universe would long ago have filled up with all the extra energy generated out of nowhere by asymmetric particle interactions.

        Something like dark energy, maybe? Not that I believe for a minute that there's anything to this, but if there is it could explain dark energy and the accelerating expansion of the universe.

    • Re:It's a Dean Drive (Score:5, Informative)

      by thomst ( 1640045 ) on Tuesday October 15, 2019 @08:38AM (#59308978) Homepage

      Antique Geekmeister observed:

      See https://en.wikipedia.org/wiki/... [wikipedia.org] . John Campbell, the editor of Analog science fiction and science fact, was a strong proponent of the Dean drive, which never did work if hung on a pendulum to eliminate rhythmic friction with the surface it rested on.

      John W. Campbell was a brilliant editor. He was also smart as all get out.

      Unfortunately, he had a collection of blind spots [wikipedia.org] that led to him promoting Dianetics, as well as the Dean Drive - and to thunderous denunciations of medical research that established the strong link between smoking and lung cancer. He was still denying that nexus when lung cancer killed him.

      Campbell liked to argue, and he was unafraid to play devil's advocate, even to the extent of didactically defending points of view that he himself did not espouse. Isaac Asimov called him "overbearing" and Robert A. Heinlein refused to submit stories to Analog after Campbell rejected one which implied that the protagonist and the ingenue had had sex. Were it not for the fact that he almost singlehandedly created the modern science fiction magazine from its earliest, pulpiest, least literary precursors, he'd rightly have been entirely dismissed as a mere argumentative crank

      But, yeah, absolutely the Dean Drive ...

      • My Erector set had a project where the motor lifted a hammer and let it go, where it slammed down and pushed the wheel-less skid along. They pointed out it wouldn't work in space.

        I imagine any tricks that temporarily increase mass on one end of something to tug a ship along would lose a trivial amount of energy in such a transaction, and the energy reclaimed un-massing it would be missing at least that much.

      • by kbahey ( 102895 )

        ... promoting Dianetics, ... thunderous denunciations of medical research that established the strong link between smoking and lung cancer. He was still denying that nexus when lung cancer killed him.

        That is interesting.

        I was reading about Hugh Everett [wikipedia.org], who was a scientist (not just an editor), and proposed the Many-worlds interpretation [wikipedia.org].

        The interesting part is the similarity with Campbell in that both were affected by Dianetics, and distrusted medicine. As a result, according to Everett's son, he ate as he

      • Asimov described Campbell as someone who "would spend hours convincing you that black was white, and then, when you were ready to die for your new belief, turn around and try to convince you that white was plaid."

    • But you have to be prepared to be embarrassed.

      Ok, prepare to be embarrassed. Mass does not increase with speed. As every physics student learns in their intro relativity course it is something called a Lorentz invariant and is constant for everyone in all inertial frames. We use this fact all the time in particle physics to help identify particles. Momentum is "gamma*mv" but the gamma comes from the relativistic velocity. In classical mechanics, we define velocity as rate of change of displacement with respect to time but in relativity everyone's spac

    • If you stop looking at the internal details and just look at this as a closed system then what you have a box that is going some speed. That is on average all the parts are going some speed. it should not matter what happens inside the box. For example, electric currents flowing in the box are traveling at relativistic speeds. Surely these would also show up as relativistic forces all the time.

      I suspect that in whatever frame the mass increases one also finds the speed slows down conserving momentum.

      • That was exactly the conclusion that I came to.

        Either the momentum and energy are conserved within the box, or they're "pushed out the back" of it. If there's not a mechanism for "pushing it out the back", the box won't be going forward. Doesn't matter what happens inside it.

        About the only other thing I could think of to move it in space, which he is not proposing, is warping space-time in front of it such that it's "sucked forward". There are really limited ways to move an object in space. You're either pu

      • If you stop looking at the internal details and just look at this as a closed system...

        You do not even need to do that. Relativity is mathematically invariant under translation i.e. if I change the physical location and even direction of a system I am calculating then the result remains exactly the same. This does not rely on physics it is a mathematical property of the theory. Another mathematical rule is Noether's theorem which, again purely mathematically, shows that any theory that has a symmetry also has a conserved quantity. Conservation of momentum is associated with the symmetry of i

        • Electrical and magnetic fields also have energy & momentum which are transformed relativistically. The transformation of EM fields was literally the centerpiece of Einstein's paper on relativity, which is why it's entitled "On the electrodynamics of moving bodies".

          If there appears to be an "out" it is probably because the author was computing only the momentum & forces on the particles, and not that delivered by the EM fields, likely back to the source of the particle accelerator. For most purpose
      • by sjames ( 1099 )

        I suspect the problem arises from doing a series of static analysis rather than a dynamic analysis. It almost looks like it could work because the analysis doesn't cover the acceleration to relaticistic speed and the accompanying decelleration in the other half of the cycle. Do a more complete analysis and the "mysterious" missing momentum will be found and it will exactly cancel any apparent change in the momentum of the system.

        It's just too easy to complicate a simple system until you can defy your own a

        • by ceoyoyo ( 59147 )

          The whole relativistic mass thing is a bit of a complicating factor. What he's really proposing is to pack more energy into the ring when it's moving in one direction, and pull that energy out when it's moving the other direction.

          According to E^2 = (pc)^2 + (m_0*c^2)^2, energy carries momentum, so the transfer of energy from the box to the ring and back (no matter how you accomplish it) will involve a transfer of momentum as well.

          The situation where you throw mass onto the ring isn't any different than if t

  • by m76 ( 3679827 )

    Skepticism is never unfortunate. Faith has no place in science.

    • Re:Never (Score:5, Insightful)

      by rednip ( 186217 ) on Tuesday October 15, 2019 @07:03AM (#59308718) Journal
      When skepticism is driven by agenda rather than curiosity, it can be unfortunate; Climate change deniers are now the classic case of a noise machine designed to muddle scientific facts.
      • > Climate change deniers are now the classic case of a noise machine designed to muddle scientific facts.

        There are no actual intelligent climate change deniers. Stop wasting our time here with painting your political opponents as kooks based on your crazy religious beliefs. The Scientific Method is alive and well outside of political circles.

      • It's kind of a selective skepticism, isn't it? Give a denialist evidence that argues against their beliefs and they'll nitpick the point beyond reason. But anything that seems to strengthen their view will be accepted without question. Skepticism just isn't skepticism unless it's applied in equal measure.

        • Give a denialist evidence that argues against their beliefs and they'll nitpick the point beyond reason.

          No, that's generally not the case in my experience. Most don't know enough to nitpick. They'll just flat-out deny or ignore.

          The problem is that if you know enough to effectively nitpick, you know enough to understand why that's not sufficient to overturn the evidence. And if you nitpick, you can be pointed at someone who did it a lot more comprehensively than you, and showed that the evidence largely holds up. If you're trying to avoid facts and evidence, learning enough to nitpick is dangerous.

      • Obligatory Dilbert: https://dilbert.com/strip/2017-05-14 [dilbert.com]
  • It's total bollocks like the EM. I expect the people here who flocked hopefully around the EM drive will flock hopefully around this drive with exactly the same flavour of specious arguments.

    If a reactionless drive produces more thrust than a photon rocket then it is equivalent to a perpetual motion machine. Eventually it will gain more kinetic energy than the input. So if you think this works or miraculously think the EM drive still works then you literally believe in perpetual motion.

    • by jabuzz ( 182671 )

      I would note that an EM drive could only be used to make a perpetual motion machine if you had some sort of 100% efficient method of turning momentum into energy. Of course such things don't exist in the real world (only the minds of physicists) and as such the EM drive even if it did work was never going to able to make a perpetual motion machine.

      To put it another way, my overbalanced wheel would be a perpetual motion machine if it was not for that pesky friction.
       

      • You don't need anywhere near 100% efficiency to turn a reactionless drive into a perpetual motion/free energy device. The concept is quite simple:

        - Mount a pair of reactionless drives on the rim of a well-balanced wheel, and place the whole thing in a near-frictionless vacuum.
        - The drives will supply constant torque under constant power, so the wheel will keep spinning faster. Eventually torque * angular velocity (=power) will exceed the power being consumed by the drives themselves by an almost arbitrari

    • by gweihir ( 88907 )

      Indeed. And they found, I believe, that the observed effects were due to some RF leak in the EM drive. Hence zero actual EM drive effect observed for that one.

    • It's total bollocks like the EM. I expect the people here who flocked hopefully around the EM drive will flock hopefully around this drive with exactly the same flavour of specious arguments.

      Oh, I do too... because the EM drive was a beautiful example of science working as it's supposed to!

      A team had an idea, so they built it, and tested it to the limits of their capability... and it seemed to work differently that expected. They had some a theory about why it seemed to work, but they never claimed with certainty that it actually did.

      Yeah, that's just normal experimental error... until another team tried it and got different, but still better-than-expected results. Maybe it's not experimental

      • by Tablizer ( 95088 )

        Any real breakthrough will probably look suspicious at first. Evolution, relativity, quantum multiverse models, and plate tectonics all raised eyebrows until the evidence kept supporting them*.

        The problem is that it's hard to seperate harebrained ideas from legitimate ones. There's probably no shortcut to rolling up our collective sleeves and test, explore, re-test, and test again.

        And often you learn interesting things along the way that may not relate to the theory being investigated. Serendipity is a big

      • Kind of but only up to a point. And this drive is beyond that point.

        Firstly, with the EM drive they first derived that it world work. Only problem is that it's mathematically impossible using the theories they used. Eventually something found the error. Do they derived it again. But the theories they used still don't allow it, do there must have been an error. Do they started spouting quantum woo. Only problem is quantum mechanics also is conservative. The maths they used provably cannot have given the resu

    • It's total bollocks like the EM.

      It's worse than the EM drive. The EM drive was an experimental observation and it is at least possible for experiments to have results that are different from theoretical predictions.

      In this case we have someone using the theory of relativity that mathematically conserves momentum to derive a prediction that does not conserve momentum. This is logically impossible and cannot be explained as "new physics we do not yet know about" since if there is such new physics then relativity would need to be correct

    • by sjames ( 1099 )

      I don't think anyone is claiming that any of these schemes produces more thrust than a photon rocket.

      Most people who were not breathless journalists believed that IF the EM drive worked, it would be found to be a Newtonian action-reaction against something that wouldn't at all violate the laws of motion. It would no more "violate the laws of physics" than magnetic propulsion of a satellite in Earth orbit. Alas, it turns out that it doesn't do anything but get warm (and perhaps in some cases act as an ineffi

  • NASA Engineer's 'Helical Engine' May Violate Laws of Physics

    It's worse than that, He's dead Jim [youtube.com].

  • by jimtheowl ( 4200185 ) on Tuesday October 15, 2019 @02:44AM (#59308358)
    "Then it would give the box a greater kick at one end than the other"

    Woudn't that 'greater kick' also be over a longer period of time in its locality?

    https://en.wikipedia.org/wiki/... [wikipedia.org]

    Perhaps a high performance simulation would be more revealing than slides.
    • by dissy ( 172727 )

      You're looking at the wrong end of the equation.

      But, Burns asks, what if the ring's mass is much greater when it slides in one direction than the other?

      *If* one can magic up some mass that wasn't there before, one could do all sorts of amazing things.
      But we so far can't magic up things into existence that don't already exist.

      So to increase the rings mass, that additional mass must come from somewhere.
      Either from matter, which means the lesser mass in one place will counter the additional mass in this place, or it comes from energy where the same rule applies, as matter and energy are the same thing as far as

      • So to increase the rings mass, that additional mass must come from somewhere.

        This is the serious flaw in his argument. The rings mass does not increase. He is relying on something called "relativistic mass" that Einstein himself warned against using. Mass is a Lorentz invariant: it is constant for all inertial reference frames: we teach this to physics students in intro relativity and we use it all the time in particle physics to help identify particles. Hence the ring's mass will not increase and, at least his explanation for how the drive works completely fails.

        • by ceoyoyo ( 59147 )

          You can get to the right answer by using relativistic mass (as tricky as that concept is). But you have to recognize that if you're going to treat energy as mass, you have to do it *all the time*, not just when it's convenient.

          You have to transfer the energy from the ship to the ring and back again. You could think of this as transferring mass, via E=mc^2, the key being that the mass doesn't just suddenly appear in the ring, it has to be transferred.

          A more correct way of looking at it is that the mc^2 part

  • by stealth_finger ( 1809752 ) on Tuesday October 15, 2019 @03:06AM (#59308382)
    So the problem is friction, or lack therof? Not this whole changing the mass of your ring slider thing?
  • by sgunhouse ( 1050564 ) on Tuesday October 15, 2019 @03:21AM (#59308400)
    Special relativity is actually pretty trivial. There will exist a frame of reference in which the impacts on both ends of the rod occur at the same velocity, which will be the average velocity of the box. Clearly if that is all that is involved then nothing is happening. There is no net acceleration.

    I can't rule out novel physics, such as zero-point energy and so on, but special relativity is a dead end in terms of "something for nothing".
    • Norther's theorem is a dead end when it comes to something for nothing. If the laws of physics don't vary with time or space than energy and momentum must be conserved.

      • by ceoyoyo ( 59147 )

        That's an ironic statement, since Noether's theorem requires that energy be created from nothing in an expanding universe, since an expanding universe is not time invariant.

  • Nothing violates the laws of physics. If something behaves in a way that we do not expect, then it becomes the new laws of physics.
    • by gweihir ( 88907 )

      The laws of Physics (just like any other law) are not set in stone. That is just a deranged idea authoritarians go for: They want absolute rules and absolute truth.

      The laws of Physics are just the current standard model of Physics. If you violate them, that means you are making an extraordinary claim and hence you need extraordinary proof, but that is it.

      • That is not just it. You can split up physics laws into a the part where the physics is cast into math, and the processing done by the mathematical framework.
        When you have an observational mismatch with theory, you can consider the remote possibility that the laws are not as general or not as accurate as assumed. But when you're doing a thought experiment inside your mathematical framework then you know beforehand that the rules of the framework will be obeyed, which includes conservation of momentum. If yo

        • by gweihir ( 88907 )

          Indeed. The important thing to always remember though is that the mathematical model is a model and not reality. Hence if some bizarre behavior happens in the model, unless and until you verify that behavior in reality, the sane thing is to expect this to be a property of the model and not of reality.

          • My point , which I'm afraid I didn't explain well, was that this NASA guy comes up with a thought experiment. This is a case of working inside the model, of following the logic of the system. He cannot even get the benefit of the doubt. He's just wrong.

  • Until the point where you actually *measure* the results, collapsing the wave function, and nope, it doesn't work...

  • The ring that goes back and forth has less mass at one end, and more mass at the other. Since "variable mass" matter doesn't exist, the only other way is to tack extra mass to the ring at one end and ditch it at the other - and lose that extra mass forever, obviously, since it would cancel out the thrust if some mechanism brought the extra mass back to the starting point during the second end of the cycle.

    In other words, it's a reaction engine. Duh...

    • Since "variable mass" matter doesn't exist, the only other way is to tack extra mass to the ring at one end and ditch it at the other - and lose that extra mass forever

      The "brilliant" idea for this helical engine, thanks to relativity and E=mc^2, mass and energy are linked [softschools.com], so if you trust the ring in one direction at relativistic speeds, it would have more mass than on the way back at more conventional speeds.
      It completely falls apart because as several other /.ers have pointed in the thread there's a ~tiny bit~ more stuff happening according to special relativity than just "things get heavy".

      Probably if more precise simulation were done (or a prototype actually build an

      • by guruevi ( 827432 )

        True, but you need to find something to do with the energy released in the conversion (if you expel it you lose mass). You also need a lot of energy to get the rod to that speed which makes it kind of useless as a driving mechanism.

        Otherwise you're just trying to invent a perpetuum mobile.

  • by Opportunist ( 166417 ) on Tuesday October 15, 2019 @05:23AM (#59308542)

    I don't see this gain a lot of traction.

  • "...we obey the laws of thermodynamics!" https://www.youtube.com/watch?v=Dc-m9dumEaw [youtube.com]
  • This doesn't work because you're shuttling mass back and forth two different ways. One way the relativistic particle carries its mass plus the mass of the energy. The other way the mass of the particle goes by itself while the mass of the energy is carried by, say, electricity to a battery, to launch the next particle. Everything is conserved and the device goes nowhere.

  • Basically his whole scheme is based on (his understanding of) special relativity. That means he has to apply the concepts of special relativity consistently. You can't just mix in a bit of nonrelativistic physics (unless it also holds in special relativity) and expect it to work properly.

    https://en.wikipedia.org/wiki/... [wikipedia.org]
    (yeah, wikipedia, but they usually get these things right).

    See the 6th slide of the presentation.

    Essentially it says, the momentum (in z-direction) can be changed without applying a force in

    • "Why didn't he (a) scour the internet and at least check the basics (instead of running numbers through silly excel sheets), and (b) talk to some expert who knows this stuff (e.g. someone giving lectures in special relativity) and can discuss the obvious problems?"
       
      Because these people are Nutters. They just want to believe. They are incapable of discussion. They are anti-Science and are basically like any other religious zealot.

      • by gotan ( 60103 )

        Well, this guy works at NASA as "Manager, Science and Technology Office" at "Marshall Space Flight Center".

        I would think that post comes, if not with a solid background in physics, at least with access to people that have such a background.

        • If he has such access to experts, he isn't using it.

          The equations of motion of charged particles in electromagnetic fields conserve 4-momentum, so anything derived (correctly) from those equations will also conserve 4-momentum. It exactly the same reason the EM drive can't work and that no mechanical perpetual motion machine can work. If conservation laws are obeyed in the underlying equations, they will be obeyed in any complex system based on those equations.

          If the claim is that Maxwell's equations, or

        • by ceoyoyo ( 59147 )

          Generally any post at an academic institution that comes with the title "Manager" or "Director" is mostly concerned with the ability to separate donors from their money.

  • It just means our laws are not complete.

  • It is not possible to push against the relativistic mass because it is not real it is a misconception about what is actually happening. It helps people understand relativity but also confuses the point. These videos are very helpful in understanding the difference https://youtu.be/LTJauaefTZM [youtu.be], https://youtu.be/A2JCoIGyGxc [youtu.be]
    • by ceoyoyo ( 59147 )

      If you expand the gamma term in the formula for relativistic mass you recognize that relativistic mass is really rest mass plus energy. Rest mass itself is really intrinsic mass plus energy, which, for any non-elementary particle, is dominated by the energy part.

      So really, *both* relativistic mass and rest mass can be regarded as equally fictional. However, both can work as valid conceptual and calculation aids, provided you use them consistently.

      The error in the present story seems to be that the guy who p

      • by ceoyoyo ( 59147 )

        PS: since your mass is dominated by the kinetic energy of the quarks and gluons that make you up, you can argue that, to fairly high precision, you've only ever pushed on relativistic mass.

  • a core physical law

    That still a 'law' which is described/decided by man to understand/explain a specific situation, but there are still more than enough situations which cannot be explained with the current 'laws of physics' we have.. So it's also very possible that the 'laws' man has described may be flawed..

  • I, for one, wouldn't mind seeing it tested under stringent, 3rd party controls. The inventor himself suspects it may fail (and it probably will) but it's still novel enough to give 'er a spin. If the worst thing that happens is that relativity notches yet another victory, I'm good with that too.
  • ... imagine a frictionless surface.
  • If this device doesn't work it will still be an interesting data point. From relativity we believe that an objects mass increases as it's velocity approaches the speed of light. From Newton we believe that an elastic collision imparts energy proportional to the speed and mass of the object.

    If this device works then great! We'll have a flaw in conservation of momentum.
    If it doesn't work the great! We'll have a flaw in relativity.

    Both of those concepts have been banging around for generations without anyo

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