from the Would-an-EnDrive-be-half-as-wide? dept.
The man behind the disputed thruster technology EmDrive has published a presentation detailing the third generation of the device. Roger Shawyer envisions EmDrive 3.0 enabling personal flying vehicles and a "space elevator without cables":
[Although] the second generation of the EmDrive can theoretically produce 3 tonnes of thrust for 1 kilowatt of power, it isn't able to move very far, so it is only useful for marine applications or for diverting asteroids, like in the new CBS sci-fi TV drama Salvation.
Shawyer has long said that his aim for inventing the EmDrive was to help get satellites into space cheaply, to enable more applications and new ways for the human race to combat global warming and the energy crisis. Essentially, the EmDrive needs to be able to move and work as well as a conventional rocket, in order to be a viable solution.
To negate these shortfalls, Shawyer's firm Satellite Propulsion Research Ltd (SPR) has also been researching a third generation of the EmDrive, which solved the acceleration problem by reducing the specific thrust.
So instead of getting 3 tonnes of thrust for every kilowatt, substantially less thrust is produced – but it can be used to accelerate the device (more about this theory can be read in a paper Shawyer presented in Beijing in 2013).
Speaking of that TV show, Roger would like some credit please.
Related UK patent application. Also at Next Big Future.
Previously: Finnish Physicist Says EmDrive Device Does Have an Exhaust
It's Official: NASA's Peer-Reviewed EmDrive Paper Has Finally Been Published
Space Race 2.0: China May Already be Testing an EmDrive in Orbit
Physicist Uses "Quantised Inertia" to Explain Both EmDrive and Galaxy Rotation
Related Stories
International Business Times writes:
A new peer-reviewed paper (open, DOI: 10.1063/1.4953807) on the EmDrive from Finland states that the controversial electromagnetic space propulsion technology does work due to microwaves fed into the device converting into photons that leak out of the closed cavity, producing an exhaust.
So how could something come out that you can't detect? Well, the photons bounce back and forth inside the metal cavity, and some of them end up going together in the same direction with the same speed, but they are 180 degrees out of phase. Invariably, when travelling together in this out-of-phase configuration, they cancel each other's electromagnetic field out completely.
That's the same as water waves travelling together so that the crest of one wave is exactly at the trough of the other and cancelling each other out. The water does not go away, it's still there, in the same way the pairs of photons are still there and carrying momentum even though you can't see them as light.
If you don't have electromagnetic properties on the waves as they have cancelled each other out, then they don't reflect from the cavity walls anymore. Instead they leak out of the cavity. So we have an exhaust – the photons are leaking out pair-wise.
After months of speculation and leaked documents, NASA's long-awaited EM Drive paper has finally been peer-reviewed and published [open, DOI: 10.2514/1.B36120] [DX]. And it shows that the 'impossible' propulsion system really does appear to work. The NASA Eagleworks Laboratory team even put forward a hypothesis for how the EM Drive could produce thrust – something that seems impossible according to our current understanding of the laws of physics.
In case you've missed the hype, the EM Drive, or Electromagnetic Drive, is a propulsion system first proposed by British inventor Roger Shawyer back in 1999. Instead of using heavy, inefficient rocket fuel, it bounces microwaves back and forth inside a cone-shaped metal cavity to generate thrust. According to Shawyer's calculations, the EM Drive could be so efficient that it could power us to Mars in just 70 days.
takyon: Some have previously dismissed EmDrive as a photon rocket. This is addressed in the paper along with other possible sources of error:
The eighth [error:] photon rocket force, RF leakage from test article generating a net force due to photon emission. The performance of a photon rocket is several orders of magnitude lower than the observed thrust. Further, as noted in the above discussion on RF interaction, all leaking fields are managed closely to result in a high quality RF resonance system. This is not a viable source of the observed thrust.
[...] The 1.2 mN/kW performance parameter is over two orders of magnitude higher than other forms of "zero-propellant" propulsion, such as light sails, laser propulsion, and photon rockets having thrust-to-power levels in the 3.33–6.67 μN/kW (or 0.0033–0.0067 mN/kW) range.
Previously: NASA Validates "Impossible" Space Drive's Thrust
"Reactionless" Thruster Tested Again, This Time in a Vacuum
Explanation may be on the way for the "Impossible" EmDrive
Finnish Physicist Says EmDrive Device Does Have an Exhaust
EmDrive Peer-Reviewed Paper Coming in December; Theseus Planning a Cannae Thruster Cubesat
A Chinese newspaper and other sources are reporting that China is already testing an EmDrive thruster in space, aboard the Tiangong-2 space station:
[Researchers] in China have announced that they've already been testing the controversial drive in low-Earth orbit, and they're looking into using the EM Drive to power their satellites as soon as possible.
Big disclaimer here - all we have to go on right now is a press conference announcement [archive.is] and an article from a government-sponsored Chinese newspaper (and the country doesn't have the best track record when it comes to trustworthy research).
[...] But what the China Academy of Space Technology (CAST) team is saying also corresponds with information provided to IB Times from an anonymous source. According to their informant, China already has an EM Drive on board its version of the International Space Station, the space laboratory Tiangong-2.
[Continues...]
A physicist is using a theory he advanced to explain how EmDrive could work to explain how dwarf galaxies can be held together without the requirement of dark matter:
British physicist Dr Mike McCulloch, who previously used quantised inertia to explain how the controversial electromagnetic space propulsion technology EmDrive works, says that he has new evidence showing his theory can also explain galaxy rotation, which is one of physics' biggest mysteries. McCulloch, a lecturer in geomatics at Plymouth University's school of marine science and engineering, says he now has even more evidence that his "new physics theory" about quantised inertia works, and that it makes it possible to explain why galaxies are not ripped apart without using theory of dark matter.
[...] There are 20 dwarf galaxies in existence from Segue-1 (the smallest) to Canes Venatici-1 (the largest), and dark matter is only meant to work by spreading out across a wide distance, but it is still used to explain dwarf galaxies, even though this requires dark matter to be concentrated within these systems, which is implausible. Instead, McCulloch asserts that quantised inertia can be used to explain how galaxies rotate without using dark matter, and he has written a paper that has been accepted by the bi-monthly peer reviewed journal Astrophysics and Space Science.
Reprint of the IBT link here.
From the abstract of Low-acceleration dwarf galaxies as tests of quantised inertia (DOI not yet published):
Dwarf satellite galaxies of the Milky Way appear to be gravitationally bound, but their stars' orbital motion seems too fast to allow this given their visible mass. This is akin to the larger-scale galaxy rotation problem. In this paper, a modification of inertia called quantised inertia or MiHsC (Modied inertia due to a Hubble-scale Casimir effect) which correctly predicts larger galaxy rotations without dark matter is tested on eleven dwarf satellite galaxies of the Milky Way, for which mass and velocity data are available. Quantised inertia slightly outperforms MoND (Modied Newtonian Dynamics) in predicting the velocity dispersion of these systems, and has the fundamental advantage over MoND that it does not need an adjustable parameter.
Previously: Study Casts Doubt on Cosmic Acceleration and Dark Energy
Dark Matter Beats its Latest Challenge
Emergent Gravity and the Dark Universe
Space Race 2.0: China May Already be Testing an EmDrive in Orbit
Milky Way is Not Only Being Pulled—It's Also "Pushed" by a Void
(Score: 3, Disagree) by ledow on Saturday August 12 2017, @09:58PM (12 children)
Same place as all the other EMDrives.
In the bin, along with the ECat.
Nothing past experimental error has ever been proven by any of them and if that video is the INVENTOR'S explanation of how it works, then to my mind it's dead in the water already. And the biggest proven effects - in Earth-based experiments - are heat and magnetic fields caused by the very power cabling that is "powering" it, causing a tiny force on the thing in a certain direction. In space, under it's own power, those forces wouldn't even be present for the most part, and when removed from the data, experimental error is all that's left.
Snakeoil and bollocks.
(Score: 4, Disagree) by kaszz on Saturday August 12 2017, @11:17PM (10 children)
There's plenty of online videos where experimenters verify the thrust. It's small, but it's there.
What I don't get is why not anyone just launch a test module into space and falsify the whole deal. Unless some people have an interest to keep it under wraps..
If the EMdrive can produce 29 kilonewton of thrust for 1 kilowatt of power reliably. Then we got hovering saucers right now. It's just to go ahead and build them.
I noticed some changes since the first version in version 3 [emdrive.com]:
* RF at 1.5 GHz instead of standard 2.4 GHz microwave oven.
* The large side surface being liquid hydrogen (LH2) cooled YBCO. This should mean a temperature below 14.01 kelvin.
* Improved thrust at 1.54 kN / kWm. (what unit is this?)
* Piezoelectric elements (to alter thrust vector?).
* Feedback detector antenna.
Obviously the liquid hydrogen will not come cheap and the whole package now has a significantly increased weight.
(Score: 4, Insightful) by HiThere on Saturday August 12 2017, @11:44PM (3 children)
IIUC, the one you're referring to is the version one of the EMDrive. And when I read yesterday that appeared to be the only one actually ever built. Versions 2 and 3 require some sort of superconductor, so that probably means liquid helium. Patent applied for doesn't mean that an actual model has ever been built. Neither does patent granted...though it OUGHT to mean a working model had been demonstrated to the patent examiner.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 2) by kaszz on Sunday August 13 2017, @12:06AM (1 child)
emdrive.com/3GEMDrive.pdf is the version one?
(Score: 2) by HiThere on Sunday August 13 2017, @06:42PM
Sorry, don't know or have a link. Until something definite turns up I'm not going to be real interested...though I sure would have been when I was younger. Dreaming with a possible reality can be great fun.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 2) by JoeMerchant on Sunday August 13 2017, @08:29PM
MRIs have been running LN2 superconductors for a long time now.
🌻🌻 [google.com]
(Score: 2, Informative) by pinchy on Sunday August 13 2017, @01:27AM (5 children)
I read last year that china was planning on doing just that.
A search pulled up this:
https://www.sciencealert.com/the-impossible-em-drive-is-about-to-be-tested-in-space/ [sciencealert.com]
Looks like someone was planning to launch on one a cubesat
(Score: 2) by kaszz on Sunday August 13 2017, @01:33AM (4 children)
Great, then we can start to get some hard data instead of this shouting match.
Any hints on when they will launch?
(Score: 2) by takyon on Sunday August 13 2017, @01:45AM (3 children)
There is an unverifiable claim that China is testing it in space: https://www.rfglobalnet.com/doc/china-claims-em-drive-technology-tested-in-space-0001 [rfglobalnet.com]
Or even on the X-37B (but USAF officials say it is a Hall effect thruster instead).
https://www.aerosociety.com/news/flights-of-fancy/ [aerosociety.com]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by kaszz on Sunday August 13 2017, @02:18AM (2 children)
What is this Hall effect thruster?
Anyway I smell military secrecy with all the fuzzy reporting. Which should mean that it's a working invention with great implications. And that there will be serious attempts at making it appear as a phony and non-working device..
Ie who benefits..
(Score: 2) by takyon on Sunday August 13 2017, @12:27PM (1 child)
https://www.google.com/search?q=Hall+effect+thruster [google.com]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by kaszz on Monday August 14 2017, @03:45AM
Ah.. "ion thruster in which the propellant is accelerated by an electric field". Seen that for years. Thought it was something new. ;)
Thought the name was ion thruster more or less.
(Score: 0) by Anonymous Coward on Sunday August 13 2017, @12:40AM
Um... I was pretty sure I read that there was a verifiable effect. What analysis did you read that put that effect within error?
(Score: 2, Interesting) by khallow on Saturday August 12 2017, @10:06PM (8 children)
I call bullshit on that one. There is no consideration of the power output of this drive. That creates problems with unbounded output power (calculation here [soylentnews.org]). The TL;DR of that link is that near constant thrust means your average power over the time the drive is active goes linearly with time. For a constant force (rather than constant acceleration) vehicle, the power output is also inversely proportional to mass, so for a light vehicle, the output power would quickly exceed the input power.
My view is that this drive is actually a glorified photonic and/or ion drive with very mundane physics as a result.
(Score: 0) by Anonymous Coward on Saturday August 12 2017, @11:13PM (3 children)
You're such a gov shill.
(Score: 1) by khallow on Sunday August 13 2017, @03:33AM (2 children)
(Score: 0) by Anonymous Coward on Sunday August 13 2017, @10:39AM (1 child)
Physics 101 also covers Newtonian mechanics, which isn't a perfect explanation either.
(Score: 1) by khallow on Sunday August 13 2017, @11:51AM
(Score: 0) by Anonymous Coward on Sunday August 13 2017, @05:50AM (3 children)
Conservation of momentum is a much more straight forward objection. Energy conversation gets very slippery, but momentum is pretty simple. In any case the EM drive seems to directly violate this. This isn't a new discovery. Like you're mentioning here if it does work as it seems to work, one of the many revolutionary results would be infinite energy production. There is a paper [arxiv.org] on this exact topic.
This is the reason that the engine is so controversial. It should not work. In every test we have been able to throw at it (including NASA contracting out 3 independent wings to develop/test their own drives) indicates that it is working. This is likely now the reason that it's seemingly being kept secretive. If, somehow, this device works it would be the most revolutionary discovery in the history of humanity. I tend to remain cynical as well. However, at this point that cynicism is only because I refuse to let myself start drooling at the potential. All evidence and testing to date indicates that it's justified to begin drooling, at least a little bit.
(Score: 1) by khallow on Sunday August 13 2017, @11:59AM (2 children)
Energy/momentum conservation is not something you trivially violate (and sorry, but this is a trivial extension of a century of EM experiments). We have never seen an example of such a violation while we have seen a lot of examples of scientific mistakes. There might be a real effect here, but it will most likely obey the laws of physics just like everything else we have ever seen does. Which is why I'm leaning towards photonic/ion propulsion as the actual mechanism behind the drive.
(Score: 0) by Anonymous Coward on Sunday August 13 2017, @04:32PM (1 child)
You can't say photonic / ionic, those are two very different things. And yes, the em drive is photonic, that was the whole point. Also, it doesn't violate conservation of momentum, the momentum comes from pure energy (photons) transferred into mass momentum.
(Score: 1) by khallow on Monday August 14 2017, @03:50AM
But two very different things that can be generated by the EM drive simultaneously. It could be both emitting microwave photons and ionizing and ejecting atoms from the surface of the device.
No, that isn't. An LED would make for a more efficient photonic drive. And of course, if you have an external light source, say like the Sun, you can double the photonic thrust from the Sun by using a mirror.
Even if that is true, and I'm not saying it is, you still have the problem that it violates other laws of physics for which we've never seen a violation. The flaws are in what is inconsistent with our other observations of reality not in what is consistent.
And sorry, I don't buy that microwaves in a box creates exotic new physics with massive potential to break conservation of energy.
(Score: 2) by JoeMerchant on Saturday August 12 2017, @10:07PM (1 child)
Two photons walk into a bar, they start dancing out of phase and exit together as a wave...
1) can they just exit through the walls since they've cancelled out each other's EM interactions?
2) when they leave without EM interaction, do they still impart momentum on their departure?
Now, let's flow 2 moles of photons per second into the same bar...
3) can we get them to align out of phase in a preferential direction?
4) are there special materials we might line 5 of the 6 sides of a box with to encourage them to go out the 6th side once they've aligned out of phase?
🌻🌻 [google.com]
(Score: 2) by kaszz on Saturday August 12 2017, @10:53PM
Does EMdrive get the Unruh radiation to align in the same direction and thus getting the maximum thrust possible?
(Score: 2) by jmorris on Saturday August 12 2017, @10:18PM (7 children)
This con artist is on "generation 3" and has yet to demonstrate a single working device. Sorry, time to call bullshit here and move on. Show me a damned flying car prototype or shut up already. I don't even care if the power system isn't ready, just stuff some big ass batteries in the thing and demo it lifting off the stage and hovering for three minutes without an umbilical cord. Do that and then shut up and take my money because I'd be ready to invest heavily. Everybody would be throwing Sagans at the guy wanting to get in on the ground floor. And the years go by, more press releases, videos of people in labs doing science looking things and white papers come out instead. Enough.
(Score: 2) by HiThere on Saturday August 12 2017, @11:47PM
It's not clear that he hasn't shown a marginally working device. But it's not clear that he has. Some examined the device and said it appeared to produce a small thrust. The amount was small enough that it would need to be tested in a satellite to be sure.
I don't think any certainty is reasonable about this thing, one way or the other.
OTOH, his proposed second and third generation devices appear to never have been built. much less tested.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 0) by Anonymous Coward on Sunday August 13 2017, @12:43AM (5 children)
Haha! Ok, was this on Rush Limbaugh or something or did Sean Hannity have a segment covering the EM drive? Did Trump tweet something about it?
I don't want to look like the AC that just keeps posting the same shit over and over again, but.. um... I was pretty sure I read that there was a verifiable effect. What analysis did you read that put that effect within error?
Jeezus, you people are just as bad as feminists. This entire species is insane.
(Score: 2) by Arik on Sunday August 13 2017, @05:56AM (4 children)
If that's accurate then it's probably the single weakest and most inefficient thruster known to man, and has absolutely no potential for the applications that Mr Shawyer claims when he's promoting it. Flying cars, for example, would never work with such a weak and inefficient thruster. So already we see a huge disconnect between the promotional claims and the supposedly tested reality. This is going to give us flying cars and cheap orbital boost? Not in a million years, not with such an anemic effect.
That's the best case. Even that, if it were true, would astonishing from a theoretical physics point of view. But what's more likely? That our entire view of the universe needs to be re-written to explain this contraption, or that the tiny thrust observed was an error? It's such a small result it has the look of rounding error, or some tiny flaw in the experimental apparatus.
Why has it still not been replicated, hmmm?
If laughter is the best medicine, who are the best doctors?
(Score: 1) by nsa on Sunday August 13 2017, @06:38AM
I've been following this news story for years. Sounds like it has been replicated, paired exhaust photons might explain the effect without rewriting established views of the universe. Indeed the power levels and applications such as flying cars sound sketchy. But satellite adjustment thrusters and long space voyages sound like potentially interesting things. I probably have misunderstood the story somewhat, but you clearly have given your implication that replication has not happened. Now, the 10X more efficient version the Chinese claim to have, is something that AFAIK has not been replicated, and AS SUCH IN THAT CASE should be dismissed (after being noted).
(Score: 1) by khallow on Sunday August 13 2017, @12:02PM
That incidentally would be about the thrust from a photonic drive, say if they had just beamed the microwaves rather than dump them into a resonance chamber.
(Score: 3, Informative) by takyon on Sunday August 13 2017, @12:25PM (1 child)
Even a really crappy EmDrive can be useful. It could outcompete ion drives by using solar power and no propellant to counteract orbital decay. Scaling it up could allow it to be used anywhere in the inner solar system, and adding nuclear could allow it to go to the outer solar system.
The technology is supposed to scale better at higher power levels and increased "Q factor".
https://www.nextbigfuture.com/2017/06/emdrive-inventor-shawyers-latest-information-on-military-applications-and-superconducting-emdrive-progress.html [nextbigfuture.com]
Some stupid error could still be behind the thrust observed even if they are measuring thrust above the sensitivity level of the instruments. Results reported by China can't be trusted [retractionwatch.com] until replicated.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 1) by khallow on Monday August 14 2017, @03:59AM
So can light pressure on the solar panels. And you don't even need to generate electricity in order to get that.
Is higher Q factor possible? As I've noted before, it sounds like a overly complex photonic or ion drive. Some of the current observed thrust per input power levels are low enough that one could improve it by merely beaming the microwaves into space.
(Score: 2, Funny) by fustakrakich on Saturday August 12 2017, @10:46PM (2 children)
We should be attractive, not repulsive..
La politica e i criminali sono la stessa cosa..
(Score: 2) by wonkey_monkey on Sunday August 13 2017, @10:35AM (1 child)
Which means what, exactly?
systemd is Roko's Basilisk
(Score: 1) by fustakrakich on Sunday August 13 2017, @07:48PM
You get to your destination by pulling it towards you. You won't get lost that way. Today's rockets, no mattered how they are fueled, are like pushing a rope. Action/reaction engines are overrated and high maintenance. Gravity and radiation are nature's way of moving things. Ride the waves. Surf's up.
La politica e i criminali sono la stessa cosa..
(Score: 2) by looorg on Saturday August 12 2017, @10:57PM
So is the show any good? From the synopsis it seems like it's Armageddon - with more politics and drama.
(Score: 3, Interesting) by wonkey_monkey on Sunday August 13 2017, @10:39AM (1 child)
Err... what?
It can produce three tonnes of thrust. It can move as far as you want.
Why can't the 3 tonnes of thrust be used to accelerate that device? It either produces thrust, or it doesn't - there isn't a different kind of "unuseful" thrust.
systemd is Roko's Basilisk
(Score: 3, Informative) by JoeMerchant on Sunday August 13 2017, @08:32PM
I read an EM article long ago that claimed the ability to make landspeeder type devices - you can repel 3 tons of thrust, until you move, then the thrust drops off dramatically. So, it could hold a landspeeder hovering, but not really make it translate along the vertical axis, which raised an interesting question to me: as you travel around a sphere, do you naturally "lift off" as you move toward any particular horizon?
Anyway: videos on YouTube or it didn't happen.
🌻🌻 [google.com]