IBTimes UK ; EmDrive Exclusive: Roger Shawyer confirms MoD interested in space propulsion tech (Full Version)

Replying to this here, as the original thread appears to be closed.

Quote from Zephir_AWT

... no EM wave is actually leaving the resonator, which Shawyer ignores completely ...

I noticed this as well. Shawyer seems to be oblivious of this important detail. There's blackbody radiation leaving the exterior of the cavity, of course, but elsewhere Bob Higgins has argued that photon recoil would be insufficient to account for the reported thrust. And it would probably not be very anisotropic.

Quote from Zephir_AWT

You can imagine the EMDrive like the boat without bottom (bottomless wooden washtub so to say), which is floating at the water surface. We're not allowed to use the paddles: everything what we can do are the ripples inside the resonator.

Allow me to modify the analogy: we're not allowed to use electromagnetic paddles, or paddles involving the ejection of regular matter from the drive. I think the conservation of momentum argument is probably a strong one, and that various theories that try to wiggle around it are likely to be unphysical thought experiments. But there is at least one possible way to have paddles and maintain conservation of momentum: neutrinos will pass right through the walls of the device like the walls don't exist.

Where would neutrinos come from? Electron capture or beta decay. Note that sapphire glass has aluminum in it, which will include 26Al, which is susceptible to electron capture. There may be other isotopes susceptible to EC or beta decay in components in one or another part of the drive. MeV decays will impart significant momentum to the neutrinos, and conservation of momentum means that an equal and opposite amount of momentum will be imparted to the device that is left behind. The shape of the cavity may have some role in bringing about the needed anisotropy of emission.

Quote from Eric Walker

Replying to this here, as the original thread appears to be closed.

Zephir_AWT wrote:
... no EM wave is actually leaving the resonator, which Shawyer ignores completely ...

I noticed this as well. Shawyer seems to be oblivious of this important detail.

Shawyer's functional theory relies on the different group velocity of the EM waves inside the tapered cavity, which in turn causes a difference in the imparted momentum at the each end. This delta is repeated at each reflection.

Calculations and experimental data are nicely summarized in a recent paper by Michael Harney at:

http://vixra.org/pdf/1604.0024v4.pdf

I haven't checked the calculations for error, but it's a place to start the discussion based on what Shawyer actually claims.

Quote from magicsound

I haven't checked the calculations for error, but it's a place to start the discussion based on what Shawyer actually claims.

Perhaps you will be willing to argue for his position? Can you summarize it in your own words? How does he account for the conservation of momentum? The device must surely be pushing off of something?

Quote from Eric Walker

Perhaps you will be willing to argue for his position? Can you summarize it in your own words? How does he account for the conservation of momentum? The device must surely be pushing off of something?

As I understand it, the momentum comes from loss of energy as the EM waves decay in the reflection process. The difference in group velocity between the two reflective ends of the cavity results in an offset in reflected momentum as well, thus producing thrust.

I sent a note to the author inviting him to join the discussion here.

/* neutrinos will pass right through the walls of the device like the walls don't exist */

I believe, that the scalar waves and sterile neutrinos are one and the same thing.

/* Shawyer's functional theory relies on the different group velocity of the EM waves */

It could be possible, if the group velocity of EM waves would decrease by their polarization (by their reflection under Brewster angle during each cycle). And I even think, that Shawyer knows about all of it very well, but he keeps these details for himself as a part of his know-how. Everything on this picture has an exact meaning: the coaxial waveguides and their length/wave phase, their pin-point entry inside the resonator, their location (quarter of resonator height) and mutually perpendicular orientation with respect to resonator axis.

/* as the EM waves decay in the reflection process */

They don't decay, they're doing spiral in similar way, like the jellyfish in water. First it creates a vortex and after then it expulses it. In essence Mr. Shawyer is generating standing EM vortices within his cavity.

Hi, my name is Mike Harney - thank you Alan for inviting me to the discussion. So the issue of momentum has come up many times - let me just ask you one question: How does a boat or airplane with a propeller create thrust? It doesn't have an internal reaction mass that it expels (the gasoline engine just turns the propeller)? Here's a great write up from NASA on it - https://www.grc.nasa.gov/www/k-12/airplane/propth.html , but suffice it to say that the propeller exists in a fluid (air or water) and the propeller's airfoil creates a pressure imbalance due to the Bernoulli effect - the same reason lift occurs on an airfoil or wing, because the air flows faster along one surface as opposed to the opposite surface to maintain equilibrium in the fluid. The propeller does the same thing - the surface of the propeller on one side is a longer path than the other and this causes the fluid to move faster along the longer surface to make up the difference in equilibrium at each sides of the propeller. the equations in the NASA link are characteristic too - notice the dependence on Velocity squared - this is important and we will come back to it. Now, the EM drive is using standing waves inside of a cavity (that's called resonance) and those standing EM waves do interact with the vacuum both inside and outside of the cavity. When I say vacuum I am talking about the quantum vacuum that has caused so much debate among theoretical physicists and experimenters. Some will say (as Dirac did in the 1920s) that the vacuum is filled with virtual particles, others will say it's energy and the truth is physics doesn't have a real answer because of one nasty inconsistency that nobody can explain - zero point energy. That's the energy of curved space (which we are in) due to General Relativity and any mass nearby and the correlation of that energy with the quantum vacuum. The vacuum says we can set any reference energy level as zero, but GR says that's not OK - the curved space has real energy. Therefore, we have a lot of energy in the vacuum - no question about it if we believe in GR but the question is, what is it manifested as when it's not creating virtual particles? It's wave energy - lots of it. Check out pilot wave theory and these experiments which describe the vacuum we know quite well - https://www.wired.com/2014/06/the-new-quantum-reality/ . We are waves - all of us, that is the new theory. Particles are just combinations of waves that have a circular structure as described in the wired article. That makes the vacuum easy - the wave energy outside of the EM cavity is pushing on it in all directions all the time. What makes a difference is when the standing waves inside the cavity have a different group velocity than the standing waves at the other end of the cavity - then a pressure differential is setup similar to the propeller in the NASA paper. In my paper, I describe how the Bernoulli effect of this wave energy in the vacuum creates a pressure differential because of the longer and shorter sides of the cavity, just like the propeller, there is a differential of thrust between each side. I also calculate, using basic wave equations for a standard wave, that the thrust is proportional to the difference between the square of the group velocities - again just like the NASA paper, you can see this in equation 2a and 2b of my paper (http://vixra.org/pdf/1604.0024v4.pdf) and the group velocity translates into the geometry of the taper of the cavity (cosine of the taper angle). So there is no problem with momentum - just like a boat in water running a propeller or a glider in the air producing lift. If you want to learn more about the wave theory of space, I recommend this link - www.wsminfo.org - Dr. Milo Wolff has made great progress explaining so many aspects of physics with this theory and I have written some papers as a coauthor with him and others to explain many of the mysteries of physics (special relativity has a few that are easy to explain - Google the GZK limit as an example). Hope this helps - just my take but it seems pretty simple to me if we are dealing with waves - no EM waves have to escape the cavity because the pressure on the sides is already there, we just create an imbalance with the EM drive.

/* but it's a place to start the discussion based on what Shawyer actually claims */

Why not, but the scalar waves mentioned in Michael Harney's (your's?) theory never appeared in Shawyer's theory anyway. He never talked about some "Bernoulli effect". He keeps his model strictly classical for not being rejected with mainstream physics immediately. Shawyer even insists, that his theory is strictly Lorentz symmetry and special relativity compliant, which may be possible only locally. Dr. Milo Wolff is a typical crackpot - he talks about scalar waves like many other aetherists, but he has no idea what's going on. Everyone, who is linking his papers here without any connection to subject is a crackpot too.

Quote from magicsound

As I understand it, the momentum comes from loss of energy as the EM waves decay in the reflection process. The difference in group velocity between the two reflective ends of the cavity results in an offset in reflected momentum as well, thus producing thrust.

Momentum is a property of things. In order for there to be an offset in momentum on either side of the Shawyer device, there must be things bearing momentum that pass through one end of the Shawyer device and leave it. Momentum cannot be transferred apart from photons or matter (or gravitons) that bear it away. If one has a taste for adventure, perhaps one might speculate that the things (e.g., photons) are disappearing at the inside wall of the cavity of the device and re-materializing outside the device.

Quote from Zephir_AWT

Eric: neutrinos will pass right through the walls of the device like the walls don't exist

I believe, that the scalar waves and sterile neutrinos are one and the same thing.

Just to be clear, I had in mind weak-charged neutrinos of the kind emitted in beta decays. How would your sterile neutrinos be produced? Are they the same thing as scalar waves? Are sterile neutrinos or scalar waves a thing?

Let's assume for the moment that scalar waves exist. According to this page, they do not have directionality. If this is the case, how can they be used to produce thrust?

The scalar waves are thing from Tesla experiments. They exhibit quite large mechanical momentum and reactive force, as follows from Podkletnov and Poher experiments. And they also manifest itself during it like nonconvergent superluminal beam. It''s all subject for long time discussion and dozens of links to various experiments.

The another question is, if the scalar waves and their reactive force are really necessary for explanation of EMDrive function. The momentum hidden in angular orbital momentum of EMWave can be substantially larger, than any momentum exerted by nonpolarized photons by itself. If we would force the EM wave inside the resonator to change its direction of polarization during subsequential reflections, it would be an effect comparable to discharging of capacitor, which can release quite a bit of momentum.

Quote

Shawyer's functional theory relies on the different group velocity of the EM waves inside the tapered cavity, which in turn causes a difference in the imparted momentum at the each end. This delta is repeated at each reflection.

And how about the momentum transfer between photons and the sides? The asymmetry will mean that there must be that, and it will exactly cancel the different transfer at the two ends.

The theory of this one is transparently wrong, and I've never seen experimental results that look different from expected artifact level (very low).

/* If this is the case, how can they be used to produce thrust? */

The scalar waves interact with vacuum fluctuations directly and they induce a space-time drag during it. Whole the vacuum is moving during it like the column of sparse but incompressible gaseous material and its motion affects all bodies in its path, which can interact with scalar waves too. It's most apparent from Poher experiments with discharging of high voltage into a Josephson junction formed with layers of superconductors. Whole the arm with superconductor gets a nice kick during it. It's not some esoteric, subliminal effect but quite an impulse. Once the superconductor gets replaced with copper (also cooled with liquid nitrogen), whole the effect disappears, therefore the superconductivity is necessary here.

But the interaction of scalar wave beam with common massive bodies is way weaker. These waves interact only with special materials, which have motion for charge carriers constrained in some way: charged capacitors, magnets in repulsive arrangement, superconductors and topological insulators like the graphene. And we have no such a materials within EMDrive, despite some people point to the apparent resemblance of EMDrive cavity with asymmetric capacitor of Biefeld-Brown.

If you have a better explanation of how GR and quantum theory describe the vacuum of space, please expound upon it. Until you do, i don't think you have a license to call anybody a crackpot unless you want to use it to describe somebody (hint, maybe you?) who has no valid explanation and just wants to accept the status quo of not needing an explanation to describe inconsistencies in physics. For me, a call of crackpot does not thing but show the ignorance of somebody who knows how to call names but doesn't understand the subject matter - show us your physics knowledge and debunk it logically if you actually know something about it.

/* And how about the momentum transfer between photons and the sides? */

All the sides of the resonator are supposed to reflect EM wave only as well as possible. The actual momentum transfer occurs during mutual interference of photons of the opposite spin at the end of resonator. Note that Shawyer device has two input waveguides, not just single one. This is because the EM waves aren't supposed to interact with wall of resonator, but with each other and to cancel their momentum during it. The EMDrive replicators should be cautious for to have standing waves inside the resonator with nodes at both ends of cavity. If you simply push random waves from magnetron into EMDrive through a wide window, you'll get a random mess of waves inside the cavity so you can expect some thrust only by accident. Many replicators even experienced the EMDrive thrust at the opposite direction - this may serve as another evidence for this theory. The shape of resonator is not actually important, the actual geometry of the wave resonance inside it is.

/* to call anybody a crackpot */

For me the crackpot is everyone, who is diluting the discussion with references to work or ideas, which don't contribute to the subject of particular discussion. The crackpot is simply person with incoherent illogical behavior and thinking, which cannot keep the subject (usually for the sake of spamming, but many crackpots are just silly). And in this case it actually doesn't matter, if the particular person points to otherwise correct theory and/or experiments or not. Has Millo Wolf something to do with EMDrive experiments? If not, why to discuss him right here?

Quote

All the sides of the resonator are supposed to reflect EM wave only as well as possible. The actual momentum transfer occurs during mutual interference of photons of the opposite spin at the end of resonator. Note that Shawyer device has two input waveguides, not just single one. This is because the EM waves aren't supposed to interact with wall of resonator, but with each other and to cancel their momentum during it. The EMDrive replicators should be cautious for to have standing waves inside the resonator with nodes at both ends of cavity. If you simply push random waves from magnetron into EMDrive through a wide window, you'll get a random mess of waves inside the cavity so you can expect some thrust only by accident. Many replicators even experienced the EMDrive thrust at the opposite direction - this may serve as another evidence for this theory. The shape of resonator is not actually important, the actual geometry of the wave resonance inside it is.

Maxwell's equations are pretty clear and allow em momentum to be calculated. They also obey conservation of momentum. So in this enclosed cavity there is no theory that gives thrust unless it is non-standard giving results that depart from normal (as Woodford's, for example). That is not what is claimed here.

Your statement here contains a whole load of assertions, some definitely false. The em field clearly does interact with the sides because it changes from free-field propagation. It seems Shawyer is using some wrong hand-waving metaphor for what happens if he says what you do.

As for cavity standing waves: they have to exist since it resonates with E component parallel to sides zero. That gives standing waves. A "mish-mash" would not be reflected. All mwave cavities used as high-Q resonators have this characteristic.

Anyway you don't need to solve Maxwell's equations. They imply conservation of momentum so no standard "theory" for this device works. There might be some non-standard theory of course.

Quote from magicsound

As I understand it, the momentum comes from loss of energy as the EM waves decay in the reflection process. The difference in group velocity between the two reflective ends of the cavity results in an offset in reflected momentum as well, thus producing thrust.

I conducted a regression analysis from data from previous studies, and found that the only significant predictors were the size of the large end and size of the small end. Basically, a larger large end and smaller small end was associated with more thrust. Oddly, variables such as Q, input power, and frequency were not significant predictors. Strange, and perhaps bothersome, that input power would not be a significant predictor of thrust. Seems like something is probably wrong here, or that it does not scale as one would expect.

Data is from the EM Drive wiki.

/* Maxwell's equations are pretty clear and allow em momentum to be calculated. They also obey conservation of momentum. So in this enclosed cavity there is no theory that gives thrust unless it is non-standard giving results that depart from normal (as Woodford's, for example). That is not what is claimed here. */

But the Maxwell's equations also allow the angular and/or orbital momentum of light. In this case the light wave propagates like the vortex ring and/or screw and its speed can be greatly lowered in this way. In this way, the photons behave like massive particles, because portion of their energy becomes connected with reference frame of photon itself. Such a photons would violate the Lorentz symmetry for example.

/* COP is not being violated. The excess power is coming from the vacuum. */

This discussion is not about COP or energy balance at all. In fact most of energy in EMDrive gets always wasted, just the minute portion of it gets utilized for thrust, so that there is absolutely no "excess of power".