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China's Radical New Space Drive

samzenpus posted about a year and a half ago | from the learning-to-fly dept.

Space 419

First time accepted submitter Noctis-Kaban writes "Scientists in China have built and tested a radical new space drive. Although the thrust it produces may not be enough to lift your mobile phone, it looks like it could radically change the satellite industry. Satellites are just the start: with superconducting components, this technology could generate the thrust to drive everything from deep space probes to flying cars. And it all started with a British engineer whose invention was ignored and ridiculed in his home country."

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I'm pretty sure it doesn't work (5, Interesting)

Electricity Likes Me (1098643) | about a year and a half ago | (#42828451)

The principles behind the EmDrive have serious theoretical problems, and the original builder and designer never tested it in a vacuum chamber.

Taking a sealed container and pumping a few kilowatts of microwaves into it, chances are any thrust developed is actually air that's getting heated up and expanding out of the container. Unless the EmDrive has been put in a vacuum chamber where this can be demonstrated to definitely not be the case (i.e. low enough that their couldn't be enough reaction mass) then it's not actually working.

Devil's (angel's?) advocate: (2, Informative)

fyngyrz (762201) | about a year and a half ago | (#42828495)

chances are any thrust developed is actually air that's getting heated up and expanding out of the container.

That effect would not last long. If it produces continuous low thrust in atmosphere, that can't be it.

More likely, as one of the groups that looked at this observed, is that all that RF (2kw) is simply interfering with the instrumentation.

Re:Devil's (angel's?) advocate: (4, Interesting)

Electricity Likes Me (1098643) | about a year and a half ago | (#42828543)

The thrust is reported to be from the large end towards the small end. The entire body of this thing that's heating up from a few kilowatts of microwaves would be warming air that flowed over the surface and thus imparting energy to it and providing a source of thrust. It would easily provide continuous thrust.

Re:Devil's (angel's?) advocate: (-1)

Nefarious Wheel (628136) | about a year and a half ago | (#42828857)

Space drive, not atmosphere drive. Space. Vacuum. *gasp* no air. If it uses air, it's not a space drive.
Gotta have some reaction mass, somewhere, even if it's coming from the walls of the maser.

Re:Devil's (angel's?) advocate: (3, Informative)

ilicas (2799301) | about a year and a half ago | (#42828927)

... , and the original builder and designer never tested it in a vacuum chamber.

maybe try reading the context of a post before inserting the snark next time?

Re:Devil's (angel's?) advocate: (3, Funny)

Jane Q. Public (1010737) | about a year and a half ago | (#42828943)

"The thrust is reported to be from the large end towards the small end. "

No, TFA says:

"... experiences a net thrust towards the wide end."

Mach-Woodward Effect (2, Informative)

sanman2 (928866) | about a year and a half ago | (#42828679)

Well, that's what people have said about the Mach-Woodward experiments, but an opposed piston design is now being tried out to isolate any noise-producing effects for remediation:

http://arxiv.org/abs/1301.6178 [arxiv.org]

Re:Devil's (angel's?) advocate: (0, Flamebait)

Anonymous Coward | about a year and a half ago | (#42828787)

All you need to know is that i gave yo mama lots and lots of thrust.

With my penis.

Re:Devil's (angel's?) advocate: (0)

mosb1000 (710161) | about a year and a half ago | (#42828869)

There's a video of it pushing an experimental apparatus, so it's definitely not an instrumentation thing. I'm not saying it works, I'm just saying that's definitely not it.

Re:Devil's (angel's?) advocate: (1)

Jane Q. Public (1010737) | about a year and a half ago | (#42828961)

"There's a video of it pushing an experimental apparatus, so it's definitely not an instrumentation thing. I'm not saying it works, I'm just saying that's definitely not it."

(Playing Devil's Advocate here): videos say next to nothing about it. I've seen videos of objects disappearing, and of Faeries. In most cases they are to be disregarded as any evidence of much of anything.

Re:Devil's (angel's?) advocate: (1)

Jane Q. Public (1010737) | about a year and a half ago | (#42828973)

Having said that, I'm playing proper Skeptic and not taking sides on whether it is at all real. As others have pointed out, there is evidence that similar effects actually exist.

Re:I'm pretty sure it doesn't work (1)

MichaelSmith (789609) | about a year and a half ago | (#42828497)

chances are any thrust developed is actually air that's getting heated up and expanding out of the container.

Sure but what if this turns out to be an efficient way to turn a small amout of gas into high energy reaction mass, with a high specific impulse?

Re:I'm pretty sure it doesn't work (1)

Anonymous Coward | about a year and a half ago | (#42828555)

We're already got those, they're called ion thrusters.

Re:I'm pretty sure it doesn't work (1)

MichaelSmith (789609) | about a year and a half ago | (#42828617)

Yeah but this to me looks like an ion thruster with lower specific impulse and higher thrust, because microwaves give the ions less kinetic energy than existing thrusters. There is a niche for high thrust ion drives.

Primitive and woefully inadequate (-1, Troll)

qbitslayer (2567421) | about a year and a half ago | (#42828975)

Anybody who thinks we are going to colonize the solar system, let alone the star systems beyond, with a bunch of cockamamie rockets is out to lunch. The idea that space propulsion is best done in a vehicle that moves forward by throwing things out the back is primitive to the extreme. Reactive propulsion precedes Newton and even Ptolemy. It's pathetic, really.

But do not let the preceding get you down because a new and fabulous era of space travel is about to be born. Soon, physicists will wake up from their stupor and realize that their understanding of motion is fundamentally flawed. We are on the verge of a breakthrough in physics that will make almost every current approach to energy production and transportation obsolete. It is based on a new analysis of the causality of motion. Essentially, Aristotle was right to insist that motion is caused. As a result, we are swimming in an immense lattice of energetic particles, an ocean of clean energy, lots and lots of free energy. Soon, we will understand enough about the lattice to exploit it for energy production and propulsion. Our future vehicles will move at tremendous speeds and negotiate right angle turns without slowing down and without incurring damages due to inertial effects. Floating sky cities impervious to earthquakes, tsunamis and bad weather, unlimited clean energy, earth to Mars in hours, New York to Beijing in minutes... That's the future of energy and travel. It will happen in your lifetime.

Physics: The Problem With Motion [blogspot.com] . You don't understand motion even if you think you do.

Re:I'm pretty sure it doesn't work (3, Informative)

Anonymous Coward | about a year and a half ago | (#42828529)

FTFA:

> Shawyer continued to produce and test more advanced demonstrators, working out elaborate ways of ensuring that the test results are valid and not the result of air currents, friction, ionization, interference or electromagnetic effects.

Re:I'm pretty sure it doesn't work (0)

Electricity Likes Me (1098643) | about a year and a half ago | (#42828559)

But again - they haven't done vacuum chamber tests - which are the only one that really matters and would exclude all the other effects.

Stick it in a vacuum chamber: if it works, then the thrust produced should be the same.

Re:I'm pretty sure it doesn't work (3, Informative)

Dan East (318230) | about a year and a half ago | (#42828539)

Some rather talented scientists evaluated this first hand:

Boeing's Phantom Works, which works on various classified projects and has been involved in space research, went as far as acquiring and testing the EmDrive, but say they are no longer working with Shawyer.

I'm sure if the drive was useful in any meaningful way it would have been utilized. So this does not bode well for the practicality of the drive for real-world applications.

Re:I'm pretty sure it doesn't work (4, Insightful)

tqk (413719) | about a year and a half ago | (#42828727)

I'm sure if the drive was useful in any meaningful way it would have been utilized.

Kind of like if Robertson screws were better than Phillips screws, they would have been utilized by Henry Ford? That stuff often doesn't work out the way sane people think it ought to.

Re:I'm pretty sure it doesn't work (2)

Theaetetus (590071) | about a year and a half ago | (#42828761)

I'm sure if the drive was useful in any meaningful way it would have been utilized.

Kind of like if Robertson screws were better than Phillips screws, they would have been utilized by Henry Ford? That stuff often doesn't work out the way sane people think it ought to.

Ah, but no one ever said that Robertson screws wouldn't work or violated fundamental laws of physics without explanation. Robertson screws are easily measurable... microwave drives, not so much. Bad analogy on you.

Re:I'm pretty sure it doesn't work (3, Informative)

jmauro (32523) | about a year and a half ago | (#42829017)

Ford wanted to use the Robinson since it was shown to be a better screw for mass production, but couldn't come to an agreement with him to license the screws in order to allow them to be made in sufficient quantity for Ford's manufacturing use.

So Ford moved on to another screw type.

Re:I'm pretty sure it doesn't work (4, Interesting)

Dahamma (304068) | about a year and a half ago | (#42829065)

No, it's not like that at all. Ford didn't choose Phillips over Robertson because Phillips was better, he did it because Robertson wouldn't license the patent and wanted to be the sole supplier. Phillips, on the other hand, did license it, and the rest is history.

On the other hand, this crackpot was so desperate to find someone to license his "drive" to he gave up trying to sell it to any American companies and tried out China...

Re:I'm pretty sure it doesn't work (3, Funny)

Dahamma (304068) | about a year and a half ago | (#42829083)

And, that makes 3 hands... next time I should proofread to limit my trite opening phrases to one per post :)

Re:I'm pretty sure it doesn't work (2, Insightful)

Forever Wondering (2506940) | about a year and a half ago | (#42828739)

Phantom Works just said they're not working with Shawyer. They didn't say the drive doesn't work. Given their nature, if the drive did work, they wouldn't disclose that because it would have profound advantages for classified work (e.g. KH-11/KH-12/etc. spy satellite maneuvering).

Re:I'm pretty sure it doesn't work (1)

mbone (558574) | about a year and a half ago | (#42829063)

No, given their nature, if it worked they would be producing glossy brochures showing spacecraft flying to Mars or where-ever. There is no reason why they would keep this a secret; the spy satellite world is not suffering from a lack of reaction mass. If they even thought it possibly could work, they would hire Shawyer.

Re:I'm pretty sure it doesn't work (1)

number11 (129686) | about a year and a half ago | (#42829103)

Boeing's Phantom Works, which works on various classified projects and has been involved in space research, went as far as acquiring and testing the EmDrive, but say they are no longer working with Shawyer.

I'm sure if the drive was useful in any meaningful way it would have been utilized.

Maybe (though Western Union first dismissed the telephone as a worthless toy). But note that they didn't say they weren't using the drive, or principles thereof. They just said they weren't working with Shawyer. If it's classified, who would know if you were infringing on a... does Shawyer even have a patent?

Re:I'm pretty sure it doesn't work (0)

Anonymous Coward | about a year and a half ago | (#42828717)

So still works for flying cars then, ill take it.

Re:I'm pretty sure it doesn't work (1)

Forty-3 (2563965) | about a year and a half ago | (#42828815)

Did you even rtfa? It is proven that this device can work. Unless they seriously screwed all this up, they will have a net thrust, air or no.

Re:I'm pretty sure it doesn't work (1)

Anonymous Coward | about a year and a half ago | (#42828861)

Yeah right. You might as well claim that perpetual motion machines have been proven.

FAQ from Dr. Shawyer answers a lot of questions. (5, Informative)

Andy Prough (2730467) | about a year and a half ago | (#42828865)

The FAQ deals with conservation of momentum, allowance for bouyancy, electromagnetic effects, convection and other issues here: http://emdrive.com/faq.html [emdrive.com] . A fantastic picture of the device on this page: http://emdrive.com/ [emdrive.com] .

Here are some of the FAQ answers:
Q. Why does the EmDrive not contravene the conservation of momentum when it operates in free space?
A. The EmDrive cannot violate the conservation of momentum. The electromagnetic wave momentum is built up in the resonating cavity, and is transferred to the end walls upon reflection. The momentum gained by the EmDrive plus the momentum lost by the electromagnetic wave equals zero. The direction and acceleration that is measured, when the EmDrive is tested on a dynamic test rig, comply with Newtons laws and confirm that the law of conservation of momentum is satisfied.

Q. Are there any convection currents which might affect the results?
A. Convection currents did not affect the results, as measurements were taken with the thrust vector up, down and horizontal. Test runs were also carried out using a thermal simulation heater to quantify the effects of change of coolant temperature.

Q. Have electromagnetic effects been taken into account? These include interactions between current-carrying conductors and between such conductors carrying RF currents and nearby metallic structures in which currents might be induced.
A. Stray electromagnetic effects were eliminated by using different test rigs, by testing two thrusters with very different mounting structures, and by changing the orientation by 90 degrees to eliminate the Earth’s magnetic field.

Re:I'm pretty sure it doesn't work (0)

gweihir (88907) | about a year and a half ago | (#42829025)

If I understand this correctly, it violates principles as fundamental as actio = reactio and conservation of impulse. Perpetuum-mobile cretins have proposed fundamentally faulty designs based on the same thing for centuries. I think the "engineer" in question is really, really incompetent and the "scientists" involved now are either under orders or complete morons.

Well... (1)

Anonymous Coward | about a year and a half ago | (#42828457)

Did he sell them a bridge too?

How about a different headline.... (4, Funny)

phantomfive (622387) | about a year and a half ago | (#42828467)

How about this headline: "Discredited British Engineer Finds New Scam Victims in China." His invention is "a closed, conical container which, when filled with resonating microwaves, experiences a net thrust towards the wide end." Sounds realistic.

Re:How about a different headline.... (5, Funny)

fustakrakich (1673220) | about a year and a half ago | (#42828491)

The most inviolable law in the universe is that everything flies pointy end first.

Re:How about a different headline.... (1)

Mitchell314 (1576581) | about a year and a half ago | (#42828597)

And goes faster if painted red.

Re:How about a different headline.... (1)

girlintraining (1395911) | about a year and a half ago | (#42828665)

The most inviolable law in the universe is that everything flies pointy end first.

Actually it's that there's no limit to human stupidity. Oh, and the chinese astronauts will probably die of lead poisoning shortly after returning.

Re:How about a different headline.... (2)

gsgriffin (1195771) | about a year and a half ago | (#42828765)

except for pigs

Re:How about a different headline.... (1)

tqk (413719) | about a year and a half ago | (#42828821)

The most inviolable law in the universe is that everything flies pointy end first.

That's Hollywood's view. In their view, explosions in space make big booming sounds and fast things make zooming sounds.

Re:How about a different headline.... (1)

Anonymous Coward | about a year and a half ago | (#42828873)

except for raindrops?

Re:How about a different headline.... (1)

gweihir (88907) | about a year and a half ago | (#42829037)

Indeed. Even classical mechanics already states this cannot work.

Re:How about a different headline.... (1)

phantomfive (622387) | about a year and a half ago | (#42829055)

Indeed. Even classical mechanics already states this cannot work.

Of course, it's good to be open to new physics and ideas, but this guy needs to come up with a plausible mechanism for how this could work, and at a minimum he needs to tell people how he did it, so we can reproduce it.

He doesn't do that, instead he talks about how none of his critics actually examined his device. Right. I hope this guy has an IPO so I can short his stock.

We can always hope, but... (1)

fyngyrz (762201) | about a year and a half ago | (#42828475)

...you'd think that if high energy in a closed, conical microwave cavity produced thrust, someone would have noticed before this. We've done a lot of work with microwaves.

Re:We can always hope, but... (2)

MichaelSmith (789609) | about a year and a half ago | (#42828503)

...you'd think that if high energy in a closed, conical microwave cavity produced thrust, someone would have noticed before this. We've done a lot of work with microwaves.

Of course it does, there are photons coming out of it.

Re:We can always hope, but... (1)

Anonymous Coward | about a year and a half ago | (#42828553)

yes. However, the net thrust from radiation is pretty damn low; math in public says it would be hard to do station keeping with solar radiation. However, if you could improve the momentum with crazy quantum shit, then this could be impressive. Unfortunately, it hasn't been demonstrated. My math isn't good enough to scratch it out, but that's generally a sign ...

Re:We can always hope, but... (1)

sfm (195458) | about a year and a half ago | (#42828667)

Yes, but they are VERY light photons

Re:We can always hope, but... (0)

Anonymous Coward | about a year and a half ago | (#42828835)

It'd be more interesting if they were dark photons, though.

Re:We can always hope, but... (2)

tqk (413719) | about a year and a half ago | (#42828871)

...you'd think that if high energy in a closed, conical microwave cavity produced thrust, someone would have noticed before this. We've done a lot of work with microwaves.

"You'd think that if the world were a sphere circling the Sun, someone would have noticed before this." I imagine Copernicus hearing something along those lines, then Galileo.

Doesn't work (5, Insightful)

joe_frisch (1366229) | about a year and a half ago | (#42828549)

From the article: "Seems to violate law of conservation of momentum". - Yup it does. Imagine putting an invisible mass-less box around the entire system. Almost nothing comes out the back (only microwave energy - more on that later). The center of mass of the box accelerates. This is a violation of conservation of momentum - one of the most well understood and best tested laws in physics. If there were some exotic high energy physics effect proposed for this at least it might be worth listening, but this is just electromagnetism - very well understood. The "group velocity / phase velocity" is just jargon that has nothing to do with this since it is the Poynting vector that carries momentum.

You CAN make a reaction drive using photons (microwaves in this case), this idea has been around for many decades. The problem is that photons carry a lot of energy relative to their momentum so it takes an enormous power source to produce any thrust. So far no one has found a practical application where there was a large enough energy (and high enough power ) source to make this practical.

There have been a lot of experiments with microwaves - I've personally worked on a 600MW pulse microwave system. There have even been attempts at microwave driven spacecraft sails. Some early experiments seemed to indicate more thrust than would be expected from momentum conservation. Eventually this was tracked down to gas absorbed on the surface being heated and released by the microwaves - essentially a conventional rocket. With very high microwave powers you can generate forces in all sorts of ways in a closed laboratory environment that would not work in space.

This will not work.

Re:Doesn't work (1)

Guy Harris (3803) | about a year and a half ago | (#42828723)

From the article: "Seems to violate law of conservation of momentum". - Yup it does.

And from the article, in more detail: "It seems to violate of the law of conservation of momentum, implied by Newton, which says that no closed system can have a net thrust. However, Shawyer says net thrust occurs because the microwaves have a group velocity which is greater in one direction than the other and Einstein's relativity comes into play."

Is the article and/or Shawyer trying to say here that "Einstein's relativity" magically makes the law of conservation of momentum go away (perhaps the idea is that Einstein's laws replace Newton's laws, or something such as that)? I may be misremembering my physics from ages ago, but I though conservation of momentum was just as much a law in Einsteinian mechanics as is Newtonian mechanics.

Re:Doesn't work (4, Interesting)

joe_frisch (1366229) | about a year and a half ago | (#42828769)

Conservation of momentum is extended in relativity to conservation of 4-momentum, basically a combination of momentum and energy. In a rest frame this means that standard Newtonian momentum is conserved, it just makes conservation also work when you are observing a system that is moving past you at relativistic speeds.

Re:Doesn't work (1)

Nehmo (757404) | about a year and a half ago | (#42828731)

Actually, the burden is on the promoter to prove that it DOES work. Until then, I have the position it doesn't, and I don't need to provide a thought experiment or anything else.

Re:Doesn't work (2, Insightful)

Anonymous Coward | about a year and a half ago | (#42828789)

Well, you'd be fascinated and intrigued by this new research and working model then? surely?

Surely you'd be interested in replicating his experiment, if only to prove it doesn't work.

Seems to be there's a lot of not-science going on here...

Re:Doesn't work (2)

gweihir (88907) | about a year and a half ago | (#42829051)

Actually, the burden is on the promoter to prove that it DOES work. Until then, I have the position it doesn't, and I don't need to provide a thought experiment or anything else.

Indeed. The claim basically violates a lot of _very_ well established physical principles. By "Extraordinary claims require extraordinary evidence" (Carl Sagan), this is already a complete fail. They do not even have the evidence ordinarily required to demonstrate that a propulsion engine works, namely a test in a vacuum chamber.

Hence I deduce this is just an ordinary scam, in line with countless others. That explanation fits the facts very well.

Re:Doesn't work (2, Insightful)

tibit (1762298) | about a year and a half ago | (#42828743)

And for everyone still reading: that's where it all ends. Nothing more to be said. Anyone who's not deluded understands that seeing any measurable thrust in such experiments is a prima facie evidence that your experimental method is broken. The better your experiment, the less thrust you should measure. That's all there's to it. Undergrad physics lab, it sounds like -- to me at least.

There's also some indirect evidence of fraud, even if non willful. How the heck is it that all such "genius", "unappreciated" world-altering inventions go through hype, secrecy, bilked investors, and nothing ever comes out of them. Nothing. Na da. Whatever grants this guy got pretty much amount to defrauding the taxpayer. You can't do this kind of shit in good faith. Pretense of being on a verge of something big is just that. It's not about any conspiracy to maintain any sort of a status quo by the "big guys/industry/villain-du-jour", or about suppressing anything. It's just that we've got basic physics figured out quite well already, and it doesn't seem like simple experiments that don't involve billion-scale investment are really going to be redefining our basic understanding of things. There are quite few engineering accomplishments to be had with small monetary involvements, but not basic law-of-nature type experimental results in physics -- not anymore, I don't think. I'd love to be proven wrong on that, of course.

Re:Doesn't work (1)

joe_frisch (1366229) | about a year and a half ago | (#42828773)

I'd agree with all that except that its actually tricky to do the experiment correctly. With lots of microwave power, high currents, etc in the system it would be easy to fool yourself. Of course if you have any brains you know it can't work from first principals and wouldn't' bother trying.

Re:Doesn't work (3, Insightful)

tibit (1762298) | about a year and a half ago | (#42828969)

I do know that it's tricky to do this stuff correctly, that why you should doubt yourself more when faced with supposedly extraordinary results. Doubt more, not less. All I remember from numerous labs that extraordinary results meant you'd have to keep redoing it until it got ordinary again. I'd have really thought that people who did any sort of engineering or physics undergrad labs should have had such basics explained to them. I'm playing with getting the 4th digit to agree well with theory in a simple mechanical pendulum, and the dreaded thing highlights that everything you thought could be ignored, can't. You have to engineer it to work -- look at all the numbers, for all effects you can think of, estimate their magnitudes, verify that you do in fact see the effects, and then mitigate. Good old experimental engineering. You get small but cumulative payoffs for diligence and a certain sense of accomplishment -- I do at least. Simple life's pleasures :)

This non-drive, given the power pumped into it, simply magnifies all the effects people can ordinarily ignore. It's a nice educational tool. I think good schools should add such a thing to their lab curriculum, so that the students will get some experience in how easy it is to fool oneself. There are probably other similarly spectacular experiments that would serve the same purpose, of course -- even a basic large mechanical pendulum.

I can't get over the fact that people with money who fund that sort of thing are so gullible, though. I mean, give me a fucking break, they seem to be just as gullible as the investors were 100+ years ago when faced with all sorts bullshit when the telegraph, telephone and electricity were getting into high gear. Hans Camenzind's little jewel of a book "Much ado about almost nothing. Man's encounter with the electron" is a sad testament to how little things change in that respect. The dumb will be parted with their money, all the time, all the same.

Re:Doesn't work (1)

Nefarious Wheel (628136) | about a year and a half ago | (#42828889)

Bravo, Joe. It's another water carburetor, and your explanation is succinct and to the point. Props.

Radiation Pressure (1)

Anonymous Coward | about a year and a half ago | (#42828937)

Microwave don't come out of the box. "law of conservation of momentum", is high school physics.

You CAN convert energy into thrust, it's called 'Radiation Pressure', so I can shine a torch on a scale in a vacuum and it pushes down the scale.

http://en.wikipedia.org/wiki/Radiation_pressure

I can shine a torch in space and generate an opposing thrust, however the effect is so tiny as to be useless. Does his apparatus improve it by group resonance? Don't know, but I can tell from reading your comment you're not even at the basic level of understanding.

Re:Radiation Pressure (1)

Michael Woodhams (112247) | about a year and a half ago | (#42829027)

Nope, GP is right. They accounted for radiation pressure with the paragraph "You CAN make a reaction drive using photons...". But the EM drive doesn't emit photons, so it can't work like this. The comment you criticize is at a much higher level of understanding than yours.

By the logic of the EM drive, a champagne bottle would also accelerate, as it is also a pressurized (approximately) conical volume.

The EM drive claims to mix a bunch of standard physics (Newtonian mechanics, electromagnetism, special relativity) to produce a violation of conservation of momentum. But all of that standard physics conserves momentum. We can immediately know that the claimed result is in error, just as if someone adds a list of even numbers and comes up with an odd total. The error is easy to spot, but we don't even need to spot it to prove that it is wrong.

(The error is pretending that by diluting something you can ignore it - in this case, the radiation pressure component in the direction of the pointy end of the cone.)

Re:Doesn't work (1)

MikeBabcock (65886) | about a year and a half ago | (#42828959)

Since when is magnetism a closed system within range of the Earth or Sun?

Re:Doesn't work (1)

phantomfive (622387) | about a year and a half ago | (#42829015)

I've personally worked on a 600MW pulse microwave system.

Yes, but did you work with resonating microwaves? Clearly that is how this guy can violate the law of thermodynamics (I would mock you now but my sarcasm wouldn't come through).

Re:Doesn't work (2)

joe_frisch (1366229) | about a year and a half ago | (#42829071)

In fact the 600MW were used to drive microwave resonators (X-band accelerator structures). Not only that but they had different group and phase velocities. I guess I should be surprised they didn't launch themselves into low earth orbit....

Maybe we should have used Tesla coils instead,

Knock Off (0)

Anonymous Coward | about a year and a half ago | (#42828575)

If it really does work let's copy the design. See how the shoe feels on the other foot.

this post will be remembered (1, Insightful)

Anonymous Coward | about a year and a half ago | (#42828585)

...as the point in interweb non-spacetime where/when slashdot's u-turn from interesting to crass became self-evident.

so long, /. been a fun 10 years. my gratitude, respect & good will as i permanently depart.

Re:this post will be remembered (5, Funny)

Daniel Dvorkin (106857) | about a year and a half ago | (#42828603)

No more Anonymous Coward posts? Whatever shall we do?

Re:this post will be remembered (0)

Anonymous Coward | about a year and a half ago | (#42828677)

Haha just fooling. I'm never gonna give you up.

Re:this post will be remembered (1)

Anonymous Coward | about a year and a half ago | (#42828697)

I'm still here! 15 years of untraceable drivel scattered over thousands of posts. I will continue to provide that into the foreseeable future. And if I ever do go, I promise not to include a message about being remembered. What a schmuck.

Conservation of momentum (0)

Anonymous Coward | about a year and a half ago | (#42828629)

A surprisingly non-sceptical article; I'd expect a bit more critical thinking from Wired. Terms like "group velocity" and quantum theory", used vaguely, don't help you avoid the fact that conservation of momentum is fundamental to modern physics. It's just as inviolable as conservation of energy.

To put it another way, this article makes Wired look just as gullible as they would if they wrote "Scientists in China have built and tested a perpetual motion machine."

Re:Conservation of momentum (1)

Anonymous Coward | about a year and a half ago | (#42828805)

A surprisingly non-sceptical article; I'd expect a bit more critical thinking from Wired.

That doesn't make any sense. Critical thinking can't debunk new discoveries, it can only show that they're out of step with previous thinking.

The test bench is the only true arbiter of what is possible and what is not. Our so-called "Laws of Physics" are merely human laws, our best approximation to describing the universe as we see it. But they're not nature's laws, she doesn't know maths and couldn't care less what we write.

Skepticism doesn't play an important role in science. Experiment and observation are all that matter, and if the results are not consistent with our "laws" then it is our laws that have to change. If it weren't so, we would still be living in caves on a flat earth.

Re:Conservation of momentum (3, Insightful)

mbone (558574) | about a year and a half ago | (#42828967)

A surprisingly non-sceptical article; I'd expect a bit more critical thinking from Wired. Terms like "group velocity" and quantum theory", used vaguely, don't help you avoid the fact that conservation of momentum is fundamental to modern physics. It's just as inviolable as conservation of energy.

To put it another way, this article makes Wired look just as gullible as they would if they wrote "Scientists in China have built and tested a perpetual motion machine."

It's really the same thing as the conservation of energy. What we really have is the conservation of four-momentum, which is standard special relativity. You can Lorentz transform one (energy) into another (momentum) (within limits).

Re:Conservation of momentum (1)

Michael Woodhams (112247) | about a year and a half ago | (#42829045)

Yeah, you should stick to reputable magazines like "New Scientist" [wikipedia.org] instead.

Ridiculed Brit? (1, Funny)

PPH (736903) | about a year and a half ago | (#42828647)

So they found the guy who invented the Triumph?

Radical form of propulsion (1)

Anonymous Coward | about a year and a half ago | (#42828661)

First Thought: it is a new space colony ship where they throw the baby girls out the back for propulsion.

emdrive.com web site explains the theory (1)

steveha (103154) | about a year and a half ago | (#42828693)

http://emdrive.com/principle.html [emdrive.com]

The inevitable objection raised, is that the apparently closed system produced by this arrangement cannot result in an output force, but will merely produce strain within the waveguide walls. However, this ignores Einstein's Special Law of Relativity in which separate frames of reference have to be applied at velocities approaching the speed of light. Thus the system of EM wave and waveguide can be regarded as an open system, with the EM wave and the waveguide having separate frames of reference.

A similar approach is necessary to explain the principle of the laser gyroscope, where open system attitude information is obtained from an apparently closed system device.

That last paragraph intrigues me. Could someone who understands ring laser physics comment on this?

I want this EmDrive to be true, but I'll wait and see. On YouTube I saw a video of a prototype EmDrive rotating itself [youtube.com] , but even if it's not fake I wonder if they have accounted for magnetic effects.

I want this to be true because space exploration would be tremendously faster if the spacecraft could accelerate the whole way without ever running out of reaction mass. Even if the acceleration was low, continuous acceleration would build to really fast velocities.

Re:emdrive.com web site explains the theory (1)

steveha (103154) | about a year and a half ago | (#42828817)

I want it to be true, but I'd bet against it:

http://xkcd.com/955/ [xkcd.com]

Re:emdrive.com web site explains the theory (0)

Anonymous Coward | about a year and a half ago | (#42828939)

More to the point:

xkcd.com/1166/ [slashdot.org]

Re:emdrive.com web site explains the theory (0, Redundant)

mbone (558574) | about a year and a half ago | (#42828925)

http://emdrive.com/principle.html [emdrive.com]

The inevitable objection raised, is that the apparently closed system produced by this arrangement cannot result in an output force, but will merely produce strain within the waveguide walls. However, this ignores Einstein's Special Law of Relativity in which separate frames of reference have to be applied at velocities approaching the speed of light. Thus the system of EM wave and waveguide can be regarded as an open system, with the EM wave and the waveguide having separate frames of reference.

A similar approach is necessary to explain the principle of the laser gyroscope, where open system attitude information is obtained from an apparently closed system device.

That last paragraph intrigues me. Could someone who understands ring laser physics comment on this?

Sure. This is BS designed to confuse and bamboozle people who don't understand special relativity or ring laser gyros.

Re:emdrive.com web site explains the theory (0)

Anonymous Coward | about a year and a half ago | (#42828989)

That sounds like the exact opposite of what is needed to explain who a laser gyroscope, where part of the point of relativity is that you get the same result regardless of your reference frame choice. The fact that you can distinguish an inertial frame from a non-inertial frame in a closed system is nothing special and goes back to basic physics, unchanged by special relativity (general relativity has something to say about inertial frame in the presence of gravity vs. non-inertial frame though).

Ungrounded assumptions (3, Informative)

DerekLyons (302214) | about a year and a half ago | (#42828711)

From TFA: Propellant can account for as much as half the launch weight of a geostationary satellite. This means that, in principle, fitting one with an EmDrive rather than a conventional drive, could halve launch costs.
 
That depends entirely on the power system needed to operate the drive. That's the real Achilles heel of various non chemical propulsion systems - they eat a lot of juice and the resulting power supplies negate most (if not all and then some) of the savings of not carrying conventional fuel.

Re:Ungrounded assumptions (1)

mosb1000 (710161) | about a year and a half ago | (#42828741)

They say the existing unit uses about half as much power to produce 4 times the thrust of the ion drive.

Re:Ungrounded assumptions (0)

Anonymous Coward | about a year and a half ago | (#42828855)

And unicorns fart rainbows.

It's a magic drive. It doesn't produce any thrust.

Re:Ungrounded assumptions (1)

mbone (558574) | about a year and a half ago | (#42829013)

And unicorns fart rainbows.

It's a magic drive. It doesn't produce any thrust.

Yes, but think of the advantages. It can have any weight or power consumption you want ! (For a small additional fee, natch.)

Are there plans so I can try it myself? (1)

mosb1000 (710161) | about a year and a half ago | (#42828735)

It doesn't sound very sophisticated, are there plans anywhere so I can build one and see for myself?

Preconceptions Are Innovation Killers (0)

BoRegardless (721219) | about a year and a half ago | (#42828745)

If I had listened to all the people who said "you can't do that" or "It won't work" or "noone has ever done that", I would have given up inventing things long ago and taken up law so I could punish people for succeeding.

You never know what you will find until you conduct the experiments.

You never know how far you go until you finish failing.

Re:Preconceptions Are Innovation Killers (2)

Desler (1608317) | about a year and a half ago | (#42828899)

Riiight. Get back to us when one of those "inventions" that break the laws of physics to work aren't bunk.

Re:Preconceptions Are Innovation Killers (1)

rahvin112 (446269) | about a year and a half ago | (#42828921)

If you are conducting experiments that violate fundamental physics they will fail every single time. You can't beat the laws that govern the universe.

Do you honestly believe that this guy has discovered a fundamental principle of the universe that violates principles that have been known and tested for almost 400 years? EM emissions, Microwaves and EM generated thrust are some of the most studied areas of human knowledge. I wouldn't bet a penny that this guy has figured out anything but how to separate unsuspecting Chinese people from their money.

If EM emissions could generate thrust like he is suggesting your monitor would probably be flying around the room. Hell even if it was regulated to some specific frequency like microwaves you'd have to strap your microwave oven down or it move around every time you turned it on. Fighter jets have large microwave based radars in their nose cones, if that generated thrust you'd have a forward facing thrust which at the power levels he's claiming would probably be more powerfull than the jet engine powering the aircraft.

Now do you understand how silly it is?

Re:Preconceptions Are Innovation Killers (1)

jeffb (2.718) (1189693) | about a year and a half ago | (#42828941)

And if you had ignored all the people who said "you can't do that" or "it won't work" or "no one has ever done that", you... probably wouldn't have survived grad school in chemistry. Or, for that matter, driver's education.

Sometimes, when everybody says you're wrong, it's because you're wrong.

You never know how far you go until you finish failing.

I don't know how far you're going to go with this.

Re:Preconceptions Are Innovation Killers (1)

gweihir (88907) | about a year and a half ago | (#42829101)

And in related news, there is a sucker born every minute and you are right on time. There _are_ people that had breakthrough insights and had trouble publishing as a result. But these were never scientifically deconstructed, but always "because that is not the way to do it". But there never, ever has been anyone that apparently managed to violate fundamental laws of physics as understood for about a century in a macroscopic context that was not a fraud. There have been lots of frauds though.

So, no, it is quite clear what is going on here. This is not a case of "you never know". It is a case of bad engineering or plain fraud.

Without wanting to comment on this particular (5, Insightful)

aussersterne (212916) | about a year and a half ago | (#42828887)

experiment (since IANAP), I do want to say that there seems to be a troubling trend amongst the best and the brightest in many STEM fields to mistake theory for reality. Theory is great and proceeds under the scientific method from empirical observation, but as we've seen throughout history, new phenomena and corner cases to arise and require theory to be amended.

It's fine to say "this is clearly unlikely to work under current theoretical understandings" but let's also refine and do the experiments to the best of our ability so that science remains scientific (i.e. nominally empirical and ultimately practical in nature). There's a difference between taking "current theory suggests this is likely to fail" as a statement of fact and mistaking theory instead to be *evidence* about experimental outcomes.

No theoretical argument can be evidence for the reality or unreality of phenomena, no matter how well-formed. That's not to say that we ought to mistake the phenomena at issue—it's obviously critical to be able to understand, rather than misconstrue, the reality that we observe—only that sometimes a generation or two of scientists seem to get complacent and imagine that they've got the world all figured out after all.

Let's continue to do, and—to the best of our ability and within reason (but with "within reason" here broadly defined—allocate resources for, actual experimentation and empirical observation of the world around us.

Not that we don't—but to my eye, the attitude that if theory doesn't support it, it's always a waste of money to test it out experimentally, is a dangerous one for the future of a science that is far less uniform, linear, and accumulative in its progress than we often tend to remember.

Re:Without wanting to comment on this particular (4, Informative)

j-beda (85386) | about a year and a half ago | (#42829053)

experiment (since IANAP), I do want to say that there seems to be a troubling trend amongst the best and the brightest in many STEM fields to mistake theory for reality. Theory is great and proceeds under the scientific method from empirical observation, but as we've seen throughout history, new phenomena and corner cases to arise and require theory to be amended.

While it is certainly worthwhile to keep an open mind and question our assumptions, there are a variety of different levels of confidence we have in different ideas. The major conservation laws (linear momentum, energy, angular momentum) are mathematically equivalent (via Noether's theorem) to symmetries of the space. If the laws of motion are independent of position then linear momentum is conserved. If linear momentum is not conserved, than the laws of motion are not independent of position. (similarly for rotation invariance angular momentum conservation and time invariance conservation of energy).

http://en.wikipedia.org/wiki/Noether's_theorem [wikipedia.org]

So this goes way beyond understanding of EM theory - if we have a case where momentum is not conserved, that will fundamentally change how we think the universe is put together. In my mind it is much much much more likely that there is error or fraud or psychosis than momentum is not being conserved.

Radical (1)

tlongren (997777) | about a year and a half ago | (#42828905)

Wish submitter could have worked "radical" in there a few more times.

Re:Radical (1)

cervesaebraciator (2352888) | about a year and a half ago | (#42828993)

For the record, it wasn't the submitter. He simply quoted the first paragraph of TFA. The whole thing gushes like that. My only surprise is that one doesn't find the phrases, "revolutionary", "iconoclastic", or "paradigm shift".

BS (3, Funny)

mbone (558574) | about a year and a half ago | (#42828907)

All the usual signs of pseudoscience.

Show it works (note : that is not the same as saying that you have shown it works), and I'll be interested. Until then, this goes in the cold fusion circular file.

3d printers for pussy (-1)

Anonymous Coward | about a year and a half ago | (#42828919)

does it have a chinese vagina attached?

Where have I seen that before? (0)

Anonymous Coward | about a year and a half ago | (#42828923)

Tony Stark's gonna be pissed when he finds out the Chinese are ripping of his arc reactor!

Rare earth metals (0)

Anonymous Coward | about a year and a half ago | (#42828965)

It's all about the rare earth metals hoarding China is doing.

coupons (-1)

Anonymous Coward | about a year and a half ago | (#42828971)

http://coupondeals.findagooddeal.info/

"Flying Cars"? WTF? (1)

gweihir (88907) | about a year and a half ago | (#42829005)

Is it non-sense time again? Flying cars are a bad idea for a large number of reasons. Those that still ignore this are not qualified to report on anything in science or technology.

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