EM-Drive – The space kicksledge rides again

The long awaited peer reviewed em-drive paper is finally out [1]. So what does this prove, that the gizmo works?

Nope. It proves absolutely nothing. Well, the peer reviewers have passed the paper so it is not absolute crapola then, I guess.

No, wait a minute. They speculate that the phenomenon could be explained by some variation of hidden variable quantum mechanics theory.

Quote from the paper:

Before providing some qualitative thoughts on the proposed physics
potentially at work in the tapered RF test articles, it will be useful to
provide a brief background on the supporting physics lines of thought.
In short, the supporting physics model used to derive a force based on
operating conditions in the test article can be categorized as a nonlocal
hidden-variable theory, or pilot-wave theory for short.[1]

Now, that’s absolute bollocks, which is obvious to anyone even remotely familiar with quantum mechanics. That chapter in the paper is completely naive and hand-wavy in it’s content.

Think about the proposition:

  1. The original theory presented by the inventor is absolute crap and has nothing to do with physical reality
  2. Couple of fringe engineers at NASA Eagleworks has managed to get they study peer reviewed
  3. The results are indistinguishable from the error margin
  4. The authors of the paper keep speculating with exotic physical theories. Again
  5. A gadget, if it works, defies the most fundamental laws of physics and is essentially an overunity device of the first kind, which can be easily proven using only high school physics

I am still calling bullshit the on space bucket and make a prediction: No exotics physics is needed to explain what is going on with the EM-Drive.


[1] Measurement of Impulsive Thrust from a Closed Radio-Frequency Cavity in Vacuum

EM-drive baloney continues

Summer vacation has given me better things to do, like wandering the Finnish wilderness, so I have not had time to follow all weird and fringe lately.

EM-drive baloney keeps to be constantly propagated, this time by a group of physicists from Finland [1].  Ah, what a treat from countrymen, again! The main contributor seems to be  Arto Annila,  a supporter of “Holistic Worldview“.

International Business Times writes [1]:

“A new peer-reviewed paper 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”

In the original paper [2], the authors deduct that:

“We infer that the EM drive expels photons in pairs where the two co-propagate with 180 degree phase difference”

Well, while I do not understand how pairs of photons like that are supposed carry out momentum and energy, let’s assume for amusement that they do.  Would that save the fabulous Em-Drive from ridicule and get us to the stars?

Whilst I do acknowledge that the writers do not seem to agree with Shawyer’s own pseudo-scientific theory, they write:

“We believe that the proposed comprehension about the paired-photon exhaust will be helpful in optimizing power to thrust by engineering the cavity so that the photons will pair with opposite phases and exit from a preferred surface.”

If correct, all this would mean that Roger Shawyer’s bucket is a very, very inefficient photon rocket. How would that be interesting or useful as a space drive. The answer is, it would not.

It would be absolutely useless.


Bummer. Double bummer.


[1] EmDrive: Finnish physicist says controversial space propulsion device does have an exhaust

[2] On the exhaust of electromagnetic drive (Arto Annila et. al.)

About fooling ourselves – and getting fooled

Ethan Siegel writes in his article [1] about how we cannot be experts in everything and how we are easily fooled by others and by ourselves.

As examples of fooled minds, bad science and scientific fraud Siegel uses for example Em-Drive and Cold Fusion.

“We like to think, as human beings, if we can only keep an open mind, that anything is possible. That if we put our minds to it, buckle down and do our research and apply ourselves 100%, we can not only understand what’s going on as well as any expert, but that we ourselves can make valuable contributions to whatever field we’re interested in. “… http://www.forbes.com/sites/startswithabang/2015/11/08/the-em-drive-nasas-impossible-engine-highlights-our-greatest-failing/

I don’t have much to add to what he says. I just wish people would understand, that while positive thinking may be important, it is equally important to practice skeptical thinking.

To avoid being fooled, if you care.

The reader comments of Siegel’s article highlight very clearly, that people actually often prefer fooling themselves, than thinking straight.

[1] The EM Drive, NASA’s ‘Impossible Engine,’ Highlights Our Greatest Failing

Silly science news – the EM-Drive is back

Roger Shawyer’s Em-Drive is back in the news, and we are seeing really funny news-lines, like The Telegraph’s super silly  ‘Impossible’ rocket drive works and could get to Moon in four hours [1].

Fours hours? Where did they get that part. Oh well, I guess someone used a calculator, but forgot to think.

Well, the fuss seems to be, that Martin Tajmar [2] from Dresden university has now confirmed, that E-Drive really produces thrust. Similar results, that NASA’s Eagleworks claimed last year [4].

“Our test campaign cannot confirm or refute the claims of the EM Drive but intends to independently assess possible side-effects in the measurements methods used so far,” said Prof Tajmar.

“Nevertheless, we do observe thrust close to the actual predictions after eliminating many possible error sources that should warrant further investigation into the phenomena.”

I am sure Tajmar is a nice guy, but he is also a big fan of funny and unrealistic theories. He has previously worked with for example anti-gravity [3]

So, taking into account that Em-Drive goes against everything we know about conservation of momentum and energy, and is in contradiction with both classical physics and relativity, which of the two is more probable:

  1. The Em-Dive really DOES work can take us to the Moon in 4 hours!
  2. The measurements by Tajmar and others are in error


Thinking is allowed. Bad science has always paired nicely with bad journalism.




[4] Space Kick-sledges and over-unity devices

Space kicksledges and overunity devices

In Finland we have a traditional vehicle called a kicksledge [1]. The sledge is propelled forward by kicking backwards against the ground, thus demonstrating the conservation of momentum.

British aerospace engineer Roger J. Shawyer have invented a kind of a space kicksledge, which is a drive that supposedly operates without propellant, but still generating thrust in some magic way.

Last month, the Wired magazine [3] wrote that Nasa had tested an other similar device, a Cannae  drive designed by one Guido Fetta.  Amazingly, they reported that the drive produced thrust. Very weak but still measurable thrust.

Ok, I have a problem with this. The device is supposed to work by bouncing microwaves in a cavity and somehow generating the thrust. I have no idea what to make out of this, but the  conclusions of Nasa test engineers are even more nonsensical.  They say in the report:

“Test campaign results indicate that the RF resonant cavity thruster design, which is unique as an electric propulsion device, is producing a force that is not attributable to any classical electromagnetic phenomenon and therefore is potentially demonstrating an interaction with the quantum vacuum virtual plasma.”

So, the space kicksledge is kicking against “quantum vacuum virtual plasma”. Now, putting it mildly, this sounds like wild speculation to me. John Baez called it “graduate-level baloney” [4].

Reactionless drive is problematic, because it is also easily an over unity device [7]. When accelerating with constant thrust without loosing propellant, the spaceships kinetic energy grows proportional to the square of the velocity.  At some point the kinetic energy can be shown to exceed the work done by the reactionless thruster and thus the spaceship becomes a perpetuum mobile.

“I cannae change the laws of physics! I’ve got to have thirty minutes!”

Shawyer says, this does not happen, because the devices thrust decreases as the velocity increases.  But I don’t know how this could be, because the principle of relativity says the laws of physics are the same in all inertial frames of reference [5].

Well, the accelerating spaceship is not an inertial frame, but if EmDrive efficiency somehow decreases when speed increases, this would anyways seem give us a method of measuring some kind of absolute speed for the spacecraft. According to relativity, such thing as absolute speed does not exist.

I may be wrong in this, but it all sounds to me like Shawyer’s space kicksledge is trying to bring back the aether theories [5].

Picture: Wikimedia Commons