Here's why scientists haven't invented an impossible space engine – despite what you may have read

July 31, 2015 by , The Conversation
From Earth to the Moon in four hours? Still impossible. Shutterstock

What if I told you that recent experiments have revealed a revolutionary new method of propulsion that threatens to overthrow the laws of physics as we know them? That its inventor claims it could allow us to travel to the Moon in four hours without the use of fuel? What if I then told you we cannot explain exactly how it works and, in fact, there are some very good reasons why it shouldn't work at all?

I wouldn't blame you for being sceptical.The somewhat fantastical EMDrive (short for Electromagnetic Drive) recently returned to the public eye after an academic claimed to have recorded the drive producing measurable thrust. The experiments from Professor Martin Tajmar's group at the Dresden University of Technology have spawned numerous overexcited headlines making claims that –- let's be very clear here –- are not supported by the science.The idea for the EMDrive was first proposed by Roger Shawyer in 1999 but, tellingly, he has only recently published any work on it in a peer-reviewed scientific journal, and a rather obscure one at that. Shawyer claims his device works by bouncing microwaves around inside a conical cavity. According to him, the taper of the cavity creates a change in the group velocity of the microwaves as they move from one end to the other, which leads to an unbalanced force, which then translates into a thrust. If it worked, the EMDrive would be a propulsion method unlike any other, requiring no propellant to produce thrust.

Fundamental problems

There is, of course, a flaw in this idea. The design instantly violates the principle of conservation of momentum. This states the total momentum (mass x velocity) of objects in a system must remain the same and is linked to Newton's Third Law. Essentially, for an object to accelerate in one direction, there must be an equal force directed the opposite way. In the case of engines, this usually means firing out particles (such as propellant) or radiation.The EMDrive is designed to be a closed system that doesn't emit any particles or radiation. It cannot possibly generate any thrust without breaking some seriously fundamental laws of physics. To put it bluntly, it's like trying to pull yourself up by your shoelaces and hoping you'll levitate.From Earth to the Moon in four hours? Still impossible. ShutterstockNonetheless, a few open-minded experimental groups have built prototype EMDrives and all seem to see it generate some form of thrust. This has led to a lot of excitement. Maybe the laws of physics as we know them are wrong?Eagleworks, a NASA-based group, built a prototype and last year reported 30-50 micronewtons of thrust that could not be explained by any conventional theory. This work was not peer-reviewed. Now, Tajmar's group in Dresden say they have built a new version of the EMDrive and detected 20 micronewtons of thrust. This is a much smaller value, but still significant if it really is generated by some new principle.

Experimental problems

Straightaway, there are problems with this experiment. The abstract states: "Our test campaign cannot confirm or refute the claims of the EMDrive." Then, a careful reading of the paper reveals this observation: "The control experiment actually gave the biggest thrust … We were really puzzled by this large thrust from our control experiment where we expected to measure zero."Yes, the control experiment designed not to generate any thrust still measures a thrust. Then there's the peculiar gradual way the thrust seems to turn on and off that looks suspiciously like a thermal effect, and then there are acknowledged heating problems. All this leads to the conclusion stated in the paper that "such a set-up does not seem to be able to adequately measure precise thrusts." Similar problems were seen by the Eagleworks group, with thrust also mysteriously appearing in their control test.Taken together, these results strongly suggest that the measured signatures of thrust are subtle experimental errors. Possible sources include thermal effects, problems with magnetic shielding or even a non-uniform gravitational field in the laboratory leading to erroneous force measurements. As a comparison, the force measured in this latest experiment is roughly comparable to the gravitational attraction between two average-sized people (100kg) standing about 15cm apart. It is an extremely small force.That the experiments detect a measureable thrust is undeniable. Where the comes from, whether it is real or erroneous, is inconclusive. That the experiments in any way confirm the EMDrive works is a falsehood. This was noted by Tajmar himself, who told the International Business Times "I believe there is no real news here yet."The experimental scientists involved have done their jobs to the best of their ability, having tested a hypothesis – albeit a spectacularly unlikely one – and reported their results. These scientists aren't actually claiming to have invented a warp drive or to have broken the laws of physics. All they're saying at the moment is that they've found something odd and unexplained that might be something new but is likely an experimental artefact that needs further study. The panoply of clickbait headlines and poorly researched articles on the topic are doing something of a disservice to their scientific integrity by claiming otherwise.

Explore further: Testing shows using microwaves to propel a craft into space might work

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spencerpencer
4 / 5 (4) Jul 31, 2015
Party pooper. :P
shavera
4.4 / 5 (7) Jul 31, 2015
Just as a VERY important note, the conservation of momentum is not a "law" like the law of gravitation, where we simply observe something to be true. It's far more strict. It's a mathematical *proof* that arises from the fact that if you take that "drive" and move it a meter to the left, it is still, fundamentally, the same physical system.

So unless all of our reality depends precisely on where we are within it (and there's no evidence this is the case, and a preponderance of evidence it is not), then the EM drive cannot break the law of conservation of momentum any more than any other perpetual motion machine can.(oh also, there's a similar law for conservation of energy and when an experiment occurs, too)
El_Nose
4.4 / 5 (9) Jul 31, 2015
it's like the e-cat

can we get a peer review so we can once and for all confirm and have a party or deny and get on with life.
.
And conservation of momentum IS A LAW -- every reaction has an equal and opposite reaction -- newton's 3rd -- but who am I

gravity IS NOT A LAW its a force
HeavyKev
2.3 / 5 (6) Jul 31, 2015
But the article states that "These scientists aren't actually claiming to have invented a warp drive or to have broken the laws of physics. All they're saying at the moment is that they've found something odd and unexplained that might be something new but is likely an experimental artifact that needs further study.". This not a definitive "NO", since further study is needed.

If there is evidence coming from the study, which is still needed, that shows there is something happening then the next step would be to find out what kind of particle is being produced to provide the thrust. If what is happening isn't completely some kind of experimental error then the problem isn't that it's defying the laws of physics. The problem is in defining how it is not. Just because you can not currently explain the effect doesn't mean that the effect isn't real
docile
Jul 31, 2015
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El_Nose
5 / 5 (1) Jul 31, 2015
my statement above is @ shavera
docile
Jul 31, 2015
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docile
Jul 31, 2015
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TopCat22
3 / 5 (4) Jul 31, 2015
Even though it is one of the fundamental laws of physics, Newton's third law can be violated in certain nonequilibrium (out-of-balance) situations. When two objects or particles violate the third law, they are said to have nonreciprocal interactions. Violations can occur when the environment becomes involved in the interaction between the two particles in some way, such as when an environment moves with respect to the two particles.

Read more at: http://phys.org/n...html#jCp
docile
Jul 31, 2015
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docile
Jul 31, 2015
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docile
Jul 31, 2015
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shavera
4.6 / 5 (10) Jul 31, 2015
El Nose: The word "law" isn't well defined in science. Newton referred to a "universal law of gravitation" in that apples falling from a tree are affected by exactly the same thing that causes planets to orbit the sun. The "law" aspect being an observed correlation between observations.

Another example of a law is "Hooke's law." The force of a spring is proportional to the amount a spring is stretched or compressed. And this one illustrates the problem of using the word "law" in physics. Hooke's law is valid.... to a point. You can stretch a spring hard enough that it doesn't stretch back. And some springs you can't compress any further than they already are. Laws have limits of applicability.

So when we get to something like Noether's Theorem (the proof I mention above), it's much much more firm than the law of universal gravitation or Hooke's law or Ohm's law etc. It's a rigorous proof from first principles, rather than an observed correlation among data.
El_Nose
3.3 / 5 (3) Jul 31, 2015
Gravity has since been redefined to an aspect of geometry per Einstein. the kinematics have seen no such revision as they too have been proved by first principals. The proof and googling is trivial and left as an exercise for the reader. ( snark )
El_Nose
3 / 5 (3) Jul 31, 2015
but seriously ... kinematics have been proved from first principals.
Egleton
3 / 5 (4) Jul 31, 2015
It really concerns me when "scientists" give more credence to their models rather than the empirical evidence.
Isn't that exactly why science broke from religious dogma?
And here we are again, back in the 14th century, with scientific dogma having replaced religious dogma.
Welcome to the Dark Ages.
Kneel before the empirical evidence, arrogant ape!
El_Nose
3 / 5 (4) Jul 31, 2015
@egleton

Thats not what this is about. Its really about the funding necessary to even test this thing. You need a vaccum chamber and a caliper to test micro Newton forces. Thats expensive. And based on principals that we know are true... and by know I mean the universe would not work if there were any deviation from these principals... your car wouldn't move, your doors wouldn't close.

Empirical evidence is the issue here and the ONLY reason people are taking time to look into it.

The issue is that no one has a concrete theory as to why it should work.
No one has a theory as to how it might improve performance.

Example: if i push a ball it will move ... if i push the ball harder it will move faster
Testable.

EM drive: If i turn it on it will move.
Test states: when you turn it on it moves. When we turned it off, it moved more for a little while, then finally stopped moving.

See the issue.
docile
Jul 31, 2015
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Egleton
1.8 / 5 (5) Jul 31, 2015
You are evading the nub of the issue el Nose.
No matter how elegant the theory, no matter how well tested, no matter how well supported by the evidence, no matter it's pedigree or heritage.

It is still a model of reality. It is not reality.

One observation can blow it clean out of the water.
If the very foundations of physics collapse because of that one observation then so be it.
To that end I offer you the quantum erasure experiment, which has demolished history and therefore cause and effect.
Everything has to be reconsidered, reworked.
docile
Jul 31, 2015
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docile
Jul 31, 2015
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docile
Jul 31, 2015
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TheGhostofOtto1923
3.5 / 5 (11) Jul 31, 2015
not supported by the science
It doesn't need to be supported by the science. The science needs to support it if the evidence is unequivocal. And science is happy to do this.

From the dresden paper:

"Nevertheless, we do observe thrusts close to the magnitude of the actual predictions after eliminating many possible error sources that should warrant further investigation into the phenomena."
like the ecat... not peer reviewed
The ecat has been peer reviewed and is now in the middle of a one year trial run, connected to a production line in an actual manufacturing facility.

Sorry I'm tired of posting the links. Try ecat world.

And again there is plenty of time for science to catch up.
Mordechai Mineakoitzen
1.5 / 5 (8) Jul 31, 2015
Recent Romanian test of EMDrive


The experimenter's first efforts seem to have produced thermal effects. In his 'results' variant, it's vertical on his measuring device, making one suspect hot air buoyancy within, still.

As I understand EMDrive, the operative notion is that the microwaves deliver impact force, similar to photons and their force on a surface…and if that's true, opposite reaction matters not since you have EM energy in effect hitting the thrust plate, adding tiny mass effects. But it remains unproven, to the extent anyone can say "definitely works". One can hope.

Some EMD experiments which have been said to work also employ a dielectric, which brings to mind the observation of T Townsend Brown, that a charged dielectric can move in the direction of its positive electrode. This video (if real) is notable because the elements are encased in epoxy minimizing any ion wind, the usual suspect.

Video: https://www.youtu...Pm5RUhP8
Whydening Gyre
4.5 / 5 (10) Jul 31, 2015
Thats not what this is about ... And based on principals that we know are true... and by know I mean the universe would not work if there were any deviation from these principals... your car wouldn't move, your doors wouldn't close.

A slight deviation - given enough time, they won't...:-)
Empirical evidence is the issue here and the ONLY reason people are taking time to look into it.
The issue is that no one has a concrete theory as to why it should work.
No one has a theory as to how it might improve performance.

Example: if i push a ball it will move ... if i push the ball harder it will move faster
Testable.

EM drive: If i turn it on it will move.
Test states: when you turn it on it moves. When we turned it off, it moved more for a little while, then finally stopped moving.

See the issue.

It's "coasting"...?
PhysicsMatter
2.7 / 5 (7) Jul 31, 2015
The problem is that there is no mathematical theory of physics without conservation of momentum and energy because of the fact of choosing certain mathematical (functional) space for calculations.

The conservation of energy is an assumption not the result of certain theory. This assumption is being applied to interpretation scheme or framework of the experimental results as well as definition of observables that are used for calculation of energy balance.

This issue of energy conservation came up when discussing H-theorem and Loschmidt's paradox suggesting that individual molecular collisions in microcosm deviate from momentum conservation laws and hence are conserved only on average for collective of large number of molecules.

If in reality there are no laws of energy/momentum conservation it would be hard to theoretically prove it. This is basic problem of any theory. See more:

https://questforn...reality/
Bongstar420
not rated yet Jul 31, 2015
Just wondering...which direction do things move in a gravity field?
RichManJoe
3 / 5 (6) Jul 31, 2015
I just removed the magnetron from our the microwave oven and am going to build one. I have to hurry and do this before Mom gets home.
EyeNStein
5 / 5 (2) Jul 31, 2015
http://www.emdriv...2012.pdf
If the above paper is accurate then a substantial thrust of 720mN was generated for 2.5kW in a high Q cavity.
The folk at NASA also found net thrust after eliminating all the orientation and thermal errors they could think of:- http://ntrs.nasa....052.pdf

The experiments are still mostly being done at the solder and epoxy glue level but at least some tests are with superconducting cavities and in hard vacuum: So some peer reviewed reproducible results should be forthcoming (or not).

Read more at: http://phys.org/n...html#jCp
EWH
3.4 / 5 (5) Jul 31, 2015
Regardless of whether or not EM drive works, this article ignored most of the papers and experiments on such devices. There are also theoretical papers on how this effect might work, and though they aren't all that convincing, they do give ideas to test, such as increasing the Q of the cavity, increasing the dielectric constant of the material in one end of the device, and potential non-linear power intensity effects. The (admittedly unconvincing) theory proposed by some of the researchers is that momentum is conserved by reaction against all the mass in the universe. Conservation of energy is put in by hand so that the device produces less thrust at higher velocities (though this begs the question of "velocity relative to what"). Pre-publication peer review is not a sine qua non for science, and indeed having articles discussed by scientists and the public at large is far more rigorous than the usual peer review. Nextbigfuture has several good discussions on EM/ cannae drive.
EyeNStein
5 / 5 (4) Jul 31, 2015
Sorry the Nasa paper is at:-
http://ntrs.nasa....6052.pdf
eljo
2.8 / 5 (9) Jul 31, 2015
The author of this article doesn't seem to understand the scientific method. If you observe an effect, you look for a theory; if it doesn't fit old theories, who cares? You still observe the effect.

The effect is real. Deal with it.
iluminandi
2.3 / 5 (9) Jul 31, 2015
actually there is something that threatens to overthrow the laws of physics as we know them
and it has been for over century
I am talking about Abraham–Minkowski controversy (en.wikipedia.org/wiki/Abraham%E2%80%93Minkowski_controversy)

"The Abraham–Minkowski controversy is a physics debate concerning electromagnetic momentum within dielectric media. Related theories have been put forward that, should their principles be proven, may allow the design of a reactionless drive."

"Theoretically speaking, the Abraham–Minkowski controversy is focused on the issues of how to understand some basic principles and concepts in special theory of relativity and classical electrodynamics.[23] For example, when there exist dielectric materials in space,
Is the principle of relativity still valid?"
as far as I remember this is why Einstein didn't get a nobel prise because due to this controversy we don't know if his theory doesn't give false prediction
cgsperling
1.6 / 5 (7) Jul 31, 2015
I really, really wanted this to be true, but my BS detector never dropped lower than 65% during this whole escapade.
big_hairy_jimbo
3.7 / 5 (6) Jul 31, 2015
I seem to recall reading somewhere that while the EMdrive violated Newtonian Physics, it was perfectly in line with Quantum Physics. The interaction is believed to be with the virtual particles of space.
Obviously more testing is required.
Keep in mind if we stick to what is known, then we won't learn anything new!!

Stick one in the X37 Military shuttle and see if you can change orbits slowly using solar panels to provide the power.
pauljpease
2.8 / 5 (9) Jul 31, 2015
The author of this article doesn't seem to understand the scientific method. If you observe an effect, you look for a theory; if it doesn't fit old theories, who cares? You still observe the effect.

The effect is real. Deal with it.


The effect is an experimental artifact. Like when homer simpson tried to weigh himself and measured value X, only to realize his belly was hung up on a towel rack, so his actual weight was Y, not X. They admit they measure "thrust" in a control experiment where there should be no thrust, therefore the experiment is flawed and no positive result can be claimed. Period.
Whydening Gyre
4.6 / 5 (10) Jul 31, 2015
Just wondering...which direction do things move in a gravity field?

helically towards the strongest gravitational field within a given locality...
someone11235813
2 / 5 (4) Jul 31, 2015

gravity IS NOT A LAW its a force


Is it even a force? It behaves as a force but gravity as we currently understand it is curvature in spacetime. Is it not?
Frosted Flake
1.8 / 5 (10) Aug 01, 2015
Quote : Maybe the laws of physics as we know them are wrong?

No maybe about it. This much we know for certain. And when an experiment produces results theory cannot account for, progress can be made. Or, we can throw the results away and keep the theory.

But then, as some folks noted and some didn't, science becomes religion. Imagine where we would be if Newton and Einstein And Faraday and Franklin (and on and on and on) had been treated like Galileo.
AlainCo
2.4 / 5 (11) Aug 01, 2015
That paragraph on null drive is simply a shameful fallacy, used to manipulate the reader.
This null drive was designed to check the theory of Fetta, and this refuted the theory and it produced thrust as Shawyers predicted.

there was a blank test done with a resistor that proved the test bench was working well, and the thrust (tested later in vacuum) was real.

using that trick to fool the reader cancel any credibility of the author.
Get better sources, like Yang Juan papers, or those from EW.

It is possible the EmDrive is a tricky effects, but the line of evidence today is quite impressive, and this requires more investigations, not armchair critics ans imaginary artifact claims.

This tricky effects resisted many debunking, including the latest German scientist who si a debunker, a real one, not an armchair debunker. Many tests refuted artifacts (changing position, direction, vacuum)...
The effect is linked to resonance, which eliminate thermal effects.
Egleton
3.4 / 5 (5) Aug 01, 2015
I read somewhere that NASA shone a laser into the cavity and detected a warping of space/time. If that doesn't make you excited, check your pulse.
Good to see you contribute Alain.
Osiris1
1.7 / 5 (6) Aug 01, 2015
I wrote a feedback letter to the site about this shameful slur on a working device by some shadowy 'group', the 'conversation'. Both or government and the Chinese government are testing this as we read here. It is a low thrust device of sorts, but the Chinese have demonstrated and annotated the research on one of there test beds producing .75N or thrust per 2.3-2,5 kW of power applied. Some tuning is involved as the Q of the system needs to be high for it to achieve peak performance in given geometrical configurations. Shawyer himself wrote in 2001 that either this system works or Einstein's relativity is wrong. So its forces seem weak. The ancestor of the laser, the 'maser' was a very weak and inefficient device at first as well, nothing like the 2.5MegaWatt behemoth we later mounted on a 747 that was able to shoot down ICBM's. The Chinese think they can make a working space shuttle with it if they can increase the power and thrust. This is a race we can not afford to lose.
Egleton
3 / 5 (4) Aug 01, 2015
"X-rays will prove to be a hoax." Lord Kelvin.
Him of the Kelvin scale.
Take heed, Ape.
eljo
3 / 5 (6) Aug 01, 2015
The author of this article doesn't seem to understand the scientific method. If you observe an effect, you look for a theory; if it doesn't fit old theories, who cares? You still observe the effect.

The effect is real. Deal with it.

"The effect is an experimental artifact. Like when homer simpson tried to weigh himself and measured value X, only to realize his belly was hung up on a towel rack, so his actual weight was Y, not X. They admit they measure "thrust" in a control experiment where there should be no thrust, therefore the experiment is flawed and no positive result can be claimed. Period."

No it is not. It is a real effect measured by multiple international teams and even in a hard vacuüm where thermal effects can be eliminated. Failure of one group to properly design a control experiment (how can you if you have no theory) is no reason to doubt the other endeavours. The setup works, theory will follow.
docile
Aug 01, 2015
This comment has been removed by a moderator.
Benni
2.8 / 5 (11) Aug 01, 2015
The effect is an experimental artifact. Like when homer simpson tried to weigh himself and measured value X, only to realize his belly was hung up on a towel rack, so his actual weight was Y, not X. They admit they measure "thrust" in a control experiment where there should be no thrust, therefore the experiment is flawed and no positive result can be claimed. Period.


They probably have not accounted for the expansion effects of ambient humidity. When you examine the paltry quantity of thrust generated as compared to the energy input & calculate efficiency, it is horrendous.
Mark Thomas
1.4 / 5 (11) Aug 01, 2015
It is literally a cone shaped microwave oven. The first version borrowed the magnetron from a 850 watt kitchen type microwave oven. The amount of thrust involved wouldn't lift a paperclip and could simply be due to heating one side more then the other (Pioneer Effect) or repulsion of the Earth's magnetic field. Investigate this all you want, but it will never produce any practical benefit. In 1968 a nuclear thermal rocket engine ran for 12 minutes putting out 4 gigawatts of power, but here we are nearly 50 years later playing with microwave ovens. Pathetic.
nathj72
2.8 / 5 (9) Aug 01, 2015
I dismissed this almost completely at first, but the optical measurements made me think twice. The guys that work at NASA propose that the virtual electrons and positron pairs are the material that is being used as a propellent. If this is the case, the drive should affect the density of electron-positron pairs inside it. The optical measurements produced a signal that could be similar to the Scharnhorst effect. However, until these optical measurements are done in vacuum the optical measurements could due to other more reasonable effects. The general consensus in the physics community is that momentum cannot be extracted from quantum fluctuations.

If the drive is producing thrust through virtual particles the momentum still must be conserved some how, maybe it is passed from one virtual particle pair to another before annihilation. I would check the walls of the vacuum chamber for heating effects.

My money is on measurement errors.
docile
Aug 01, 2015
This comment has been removed by a moderator.
Mark Thomas
2.1 / 5 (11) Aug 01, 2015
"Such a nuclear rocket would pollute the atmosphere for many years at the case of crash - it would be something like the Chernobyl at the high altitude."

That's it? Your recommendation is to give up on the best propulsion we have and play with microwave ovens? No wonder we have made zero progress in propulsion. How about sending the fuel up separately in hardened canisters that can survive a rocket explosion? The nuclear engine itself is only used in space where the solar wind will disperse any remnants. If we are smart, we can use ceramic pellets developed decades ago where no fuel is lost.

Anytime you find yourself saying the risk is too great, consider if better engineering or a different approach would help.
docile
Aug 01, 2015
This comment has been removed by a moderator.
bluehigh
3 / 5 (4) Aug 01, 2015
helically towards the strongest gravitational field within a given locality...
- WG

Do you know why?

It's a bit more complex than your snippet. So it's a bit annoying to see you simply repeating something from the Google Brain. Then again maybe you can explain from personal knowledge. Just checking you're not playing popularity games.

Benni
3.2 / 5 (11) Aug 01, 2015
....... until these optical measurements are done in vacuum the optical measurements could due to other more reasonable effects.
......like ambient humidity. I've seen those pictures of the NASA rigup, it is a badly sealed (?) environment for elimination external ambient gases. With all those microwaves heating & expanding waterborne gases, of course some effluent will be detected & measured.

romesh6626
1.8 / 5 (5) Aug 01, 2015
Just as a VERY important note, the conservation of momentum is not a "law" like the law of gravitation, where we simply observe something to be true. It's far more strict. It's a mathematical *proof* that arises from the fact that if you take that "drive" and move it a meter to the left, it is still, fundamentally, the same physical system.


I think that there is one way to break the 'law' of conservation of momentum - Imagine a universe where there are two kind of particles. Particle A attracts particle B but particle B repels particle A. This would lead to failure of law of conservation of momentum. So it really depends upon the nature of fundamental laws which are formulated based on observation as you said.
Andrew Palfreyman
2.3 / 5 (9) Aug 01, 2015
What a stupid headline. We know why ANYBODY has not invented an impossible ANYTHING.

Clue: It's impossible.
Whydening Gyre
4.6 / 5 (9) Aug 01, 2015
helically towards the strongest gravitational field within a given locality...

- WG
Do you know why?
Because that's the way shit works... (counterclockwise)

It's a bit more complex than your snippet. So it's a bit annoying to see you simply repeating something from the Google Brain. Then again maybe you can explain from personal knowledge. Just checking you're not playing popularity games.

More complex - agreed. No annoyment necessary, since I have no idea what "Google Brain" is. I have no direct knowledge, just direct rationalization from what I observe. Who would I being popular with?!? it's an alternative viewpoint...
Let's go do some Crown and discuss it...

docile
Aug 02, 2015
This comment has been removed by a moderator.
Benni
3.3 / 5 (12) Aug 02, 2015
helically towards the strongest gravitational field within a given locality - WG


Do you know why?

It's a bit more complex than your snippet. So it's a bit annoying to see you simply repeating something from the Google Brain. Then again maybe you can explain from personal knowledge. Just checking you're not playing popularity games.


Fewer than half those who post Commentary here & who vote, do so because they have any interest in the topic being discussed, this group is best known by their profuse quantity of name calling & profanity. The first time you call them on their name calling & profanity, they never forget it, from that point forward they troll your name no matter how much more knowledgeable you are than they about any topic under discussion, the Stumpy/Ira voting clique is endemic with this mentality simply because they cannot compete within the arena of discussions in science. I only stay here & continue posting because it galls them so much.
Uncle Ira
3.7 / 5 (15) Aug 02, 2015
Stumpy/Ira voting clique is endemic


@ Bennie-Skippy. I did not even vote on this article or write any postums yet. And I will tell you another thing too. I do not use the bad words but do sometimes call peoples names. So right now I am going to call you the couyon AND give you the bad vote for dragging me into this one before I even tried to be in it.
Mark Thomas
1.6 / 5 (7) Aug 02, 2015
"Of course not, the cold fusion already exhibits higher energy density, than the nuclear reactors - and it's completely safe. The connection with 'microwave owen", i.e. EMDrive would make it an unbeatable combination"

An unworkable power source and an unworkable drive will produce nothing but waste. Engineering is about making stuff work in real world. Nuclear power works in the real world. Cold fusion has powered nothing since 1989. Nuclear thermal rockets were favored by the Werner Von Braun, the guy who got us to the moon, for real. The EM drive is a cone-shaped microwave oven that has moved nothing. The presumably un-powered control setup put out more thrust! Rock sold physics support nuclear thermal rocket engines and the 1968 test put out 4 BILLION watts of power for 12 minutes. You've got nothing but a goofy fantasy based on wishful thinking and fundamentally flawed concepts well outside a century of physics.
Benni
3.4 / 5 (10) Aug 02, 2015
Engineering is about making stuff work in real world. ....... Nuclear thermal rockets were favored by the Werner Von Braun, the guy who got us to the moon, for real. ...... Rock sold physics support nuclear thermal rocket engines and the 1968 test put out 4 BILLION watts of power for 12 minutes.
.....speaking of which, did you see the sketch for a patent Boeing has applied for? Looks like they are trying to apply an isotope thermocouple in tandem with a fusion process as effluent to generate thrust, a step up from what Von Braun was attempting to do.
docile
Aug 02, 2015
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docile
Aug 02, 2015
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docile
Aug 02, 2015
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Mark Thomas
2.1 / 5 (7) Aug 02, 2015
"Werner Von Braun was genius, but solely adventurous and opportunist scientist . . ."

Just thinking logically and without judging him, it certainly would have been preferable to us Americans to have had a home-grown American scientist run the American space program without any question marks in his personal history. But Werner Von Braun was a genius and you cannot argue with his success, ever. I would also argue that although his past was questionable, what matters most was that he helped moved the human race forward. That is everything. To be candid, this is why I pull my punches a little less when it comes to things that don't produce real results and distract us from what does work, i.e., they are not moving us forward. After 42 years of not having left low Earth orbit (LEO), let's go with what we know works and get out there again!
Mark Thomas
2.5 / 5 (8) Aug 02, 2015
Docile, the currently generation's understanding of science and technology is undoubtedly at an all-time high. If the microwave oven cone works against all expectations, and huge chunks of modern physics are overturned, I think the current generation should be forgiven for not seeing such a bizarre occurrence. However, I wouldn't worry about this happening, because it won't.

I am sensing frustration and I share that frustration when it comes to manned space exploration. We have not left LEO since 1972. Can anybody really argue that we are incapable of doing better? But in many ways, it is amazing we are moving forward at all. Hopefully, even if the best we can do is our current glacial pace, enough of us will figure this out to make it happen. Go boldly.
docile
Aug 02, 2015
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bluehigh
not rated yet Aug 02, 2015
and I'm getting downvoted for every post.


I have helped with a bit of up voting for you. I may or may not agree with you on this subject. However your comments are interesting. Don't be concerned with the votes as they are often skewed by personal issues rather than comment content. (You should already know that, you've been around in one form or another for a while)!

Don't let the bastards grind you down.

Mark Thomas
2 / 5 (8) Aug 02, 2015
"I cannot take seriously the ethical judgment from people, who are biased in the same way, like von Braun did."

Docile, please try to appreciate that fact that the human race is trying to pull itself up from nothing. Not only was every person who made a contribution a flawed individual, it would be shocking if that weren't the case. Ok, so maybe Mother Theresa was close to perfect, who knows? But it is clear she was not typical of the human race. Not by a long shot. Here's how to begin reconcile this, ask yourself is the world better off because this person existed? The answer for Werner Von Braun is clearly yes. We all need to apply this standard to our own lives as well and work to ensure that the answer is yes.
docile
Aug 02, 2015
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docile
Aug 03, 2015
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docile
Aug 03, 2015
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docile
Aug 03, 2015
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docile
Aug 03, 2015
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docile
Aug 03, 2015
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antialias_physorg
4.2 / 5 (5) Aug 03, 2015
Ok, so maybe Mother Theresa was close to perfect, who knows?

Not really.
https://en.wikipe...riticism
(Don't get me wrong, she did a lot of good. But she was far from perfect)
docile
Aug 03, 2015
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docile
Aug 03, 2015
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docile
Aug 03, 2015
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Mark Thomas
1.7 / 5 (6) Aug 03, 2015
"which will result into similar pushing effect, like the superconductive layers did in Podkletnov/Poher experiments in impulse regime.

Docile, do you use anything other than wishful thinking to separate "frontier research" from scientific fraud? Eugene Podkletnov is a pathological liar. If it were possible to shield gravity this way, placing one side of a flywheel over the superconducting/gravity shielding disk would cause the flywheel to spin because one side would always be heavier than the other. The axis of the flywheel connected to an electric motor would give you unlimited free energy, i.e., it would be a perpetual motion machine violating conservation of energy. You should also be deeply troubled that Podkletnov's 1992 antigravity assertion is now 23 years old and we have zero working devices. Why not try the experiment yourself? You can buy a superconducting disk on Amazon for $53.
http://www.amazon...00701BXI
ogg_ogg
4 / 5 (1) Aug 03, 2015
Most discussion here misses the point: if experiment doesn't fit theory, then 1 the experiment is wrong,2 theory is wrong,or 3 interpretation is wrong (or some combination) & we know our theories are almost certainly wrong & are certainly incomplete. I hold as a fundamental Truth that experiments can NOT be wrong, rather our interpretation often is. In reading the comments, they used 2.5 kW to produce a couple dozen uN. The article claims that "no particles are emitted"-but that claim is rubbish. You just can't use 2.5 kW and not have waste heat, and I'm sure the paper makes no such claim. Also, a Newton is a force, so what does 30-50 uN even MEAN?? They ACTUALLY measured WHAT? deflection? current? what? BTW a law is a theory which has been extremely well tested. Extraordinary claims require extraordinary 'proof'.Some here would profit by assuming an engine w/perfect conversion of E to p and then running the calcs for a-centuri trip. Disappointing to the Star Trekkies.
docile
Aug 03, 2015
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Mark Thomas
2 / 5 (8) Aug 03, 2015
"Disappointing to the Star Trekkies."

Learning that my microwave oven won't carry me to Mars is hardly disappointing. I expect it to heat up leftovers, not morph into warp drive.
Mark Thomas
2.3 / 5 (9) Aug 03, 2015
Docile, apparently you are one of those people who rejects any information that does not fit with your conclusion. I am afraid we are done here.
Tangent2
not rated yet Aug 03, 2015
For anyone interested, there are several parties that are still performing ongoing research into the emdrive. Here is their discussion:
http://forum.nasa...642.6300

And here is their results so far:
http://emdrive.wi..._Results
docile
Aug 03, 2015
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Jay_C
2.3 / 5 (3) Sep 02, 2015
From the Inventor's website FAQ...

The EmDrive does not violate any known law of physics. The basic laws that are applied in the theory of the EmDrive operation are as follows:

Newton's laws are applied in the derivation of the basic static thrust equation (Equation 11 in the theory paper) and have also been demonstrated to apply to the EmDrive experimentally.

The law of conservation of momentum is the basis of Newtons laws and therefore applies to the EmDrive. It is satisfied both theoretically and experimentally.

The law of conservation of energy is the basis of the dynamic thrust equation which applies to the EmDrive under acceleration,(see Equation 16 in the theory paper).

The principles of electromagnetic theory are used to derive the basic design equations.

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