Author Topic: EM Drive Developments Thread 1  (Read 765943 times)

Offline Rodal

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Re: EM Drive Developments
« Reply #1100 on: 09/29/2014 02:59 AM »
dark matter ?

Pierre Sikivie [in 1983]  showed that dark matter axions can be detected on Earth by converting them to microwave photons in an electromagnetic cavity tuned to the axion mass and permeated by a strong magnetic field. This is the principle of the Axion Dark Matter eXperiment (ADMX) at the University of Washington in Seattle.  It uses a resonant microwave cavity within in a large superconducting magnet to search for cold dark matter axions in the local galactic dark matter halo

http://www.phys.washington.edu/groups/admx/home.html

http://www.phys.ufl.edu/~tanner/PDFS/Hoskins11prd-Hires-10Hz.pdf


<<We describe the ADMX receiver in detail as well as the analysis of narrow band microwave signals. We demonstrate the sustained use of a SQUID amplifier operating between 812 and 860 MHz with a noise temperature of 1 K. The receiver has a noise equivalent power of View the MathML source in the band of operation for an integration time of View the MathML source.>>

<<ADMX converts axions to detectable microwave photons via the inverse Primakoff effect (   http://en.wikipedia.org/wiki/Primakoff_effect  ) within a tunable, high quality factor (Q ~ 50000) microwave cavity immersed in a strong magnetic field.>>

<<The ADMX detector consists of a 1-m tall, 0.5-m diameter, copper plated, stainless steel, right cylindrical
cavity kept at 1.8 K and placed in a 7.6 T magnetic field>>

Comparing the quality factors, Eagleworks measured quality factor for the Frustum was 18,100 with a power-forward/power-reflected difference of 16.74 watts and the average measured thrust was 50.1 micronewtons. So that is Q~18,100 compared with Q~50,000 at ADMX. Also Eagleworks run a quality factor of 22000, with applied power of 2.6 watts, net average thrust of 55.4 micronewtons.

Comparing frequencies, Eagleworks run at twice the required frequency:  1936.7 MHz compared with the 812 and 860 MHz at ADMX.

We are missing the 7.6 T strong magnetic field in the Eagleworks experiment.  The only magnetic field in the Eagleworks  experiments is the one produced by the three neodymium (NdFeB Grade N42) block magnets, which is there only by chance ( to dampen the swinging and torsional oscillations of the inverted pendulum).  The magnetic damper is located about a foot away from the tested microwave device (Cannae or Frustum).

For comparison, the magnetic field intensity at the surface of a neodymium magnet is 1.25 T


So, perhaps Eagleworks should see what difference it makes to have the neodymium magnets next to the tested device  :)

« Last Edit: 09/29/2014 03:38 AM by Rodal »

Online cuddihy

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Re: EM Drive Developments
« Reply #1101 on: 09/29/2014 03:02 AM »

Ok, this is preliminary and difficult. But, regardless of theories, they claim results, they claim difficult to obtain and measure but real non classical effects. Sceptic but open minded readership is not requiring cautionary phrase "assuming any propellantless effect at all is possible" at each single slide or paragraph of the publications, but the overall tone is that they have no doubt they are onto something, and trying to improve that something. But there is nothing to improve if there is nothing, and it is very possible there is nothing, that propellantless effects (better than 1/c) is not part of reality, like FTL travels. It would be very desirable but it could be just plain impossible. No matter bright theories to explain how it could be possible, and it is certainly worth investigating such possibilities, in the end it might be just plain impossible. And that is what best contemporary theories and their theoreticians are telling. They could be wrong. They very possibly could be right, even if wrong on a lot of other things.

If all the signals are false, then there is no progress to be made by comparing the signals. For instance it is irrelevant to make a theory that better explains why a thruster could better push on vacuum with a dielectric resonator than without, it is irrelevant to make devices with dielectric resonators because seeing a signal would be better than no signal. I think that they are trying too hard to see something, and not hard enough to see nothing.

There is the device and the experiment to test the device. As for the experimental part there is a force measuring system and an enclosure around the device to insure the device is isolated from the rest of the experiment and can't expel anything or push on any wall or field. Working in a vacuum is a kind of enclosure, but it is far from sufficient. If any effect at all is possible then this enclosure is irrelevant for applications. For determining the all or nothing answer of "is the effect real ?" this enclosure is paramount. The experimenters and theoreticians here seem to put so much accent on the device, some real effort on the force measuring (but maybe not the appropriate apparatus), but not much about the enclosure.

This is now several pages back but didn't want to leave it unchallenged -- frobnicat, it's not a detour for Eagleworks or Woodward to be focusing, decades into their separate work, building thrust levels as a primary focus compared to eliminating spurious, conventional sources of potential thrust. The fact is, the effort to eliminate spurious sources can go on forever if you are pumping hundreds of watts into a box and measuring micronewtons at a small distance above the noise threshold. In Woodward's case it's been over I believe 17 years of experiments.

The one thing that changes the dynamic is if you can increase the thrust/power to the level where spurious sources of thrust are differentiated by the power level. The larger the thrust being measured, the easier it is to figure out the source.

So even if the theory is wrong, after so many years of chasing something uncertain, and if you're convinced either by the underlying theory or previous results, surely it makes sense to keep trying to increase the thrust while only slowly chipping away at the spurious potential sources.

Offline ThinkerX

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Re: EM Drive Developments
« Reply #1102 on: 09/29/2014 03:30 AM »
Quote
Pierre Sikivie [in 1983]  showed that dark matter axions can be detected on Earth by converting them to microwave photons in an electromagnetic cavity tuned to the axion mass and permeated by a strong magnetic field. This is the principle of the Axion Dark Matter eXperiment (ADMX) at the University of Washington in Seattle.  It uses a resonant microwave cavity within in a large superconducting magnet to search for cold dark matter axions in the local galactic dark matter halo

http://www.phys.washington.edu/groups/admx/home.html

http://www.phys.ufl.edu/~tanner/PDFS/Hoskins11prd-Hires-10Hz.pdf


<<We describe the ADMX receiver in detail as well as the analysis of narrow band microwave signals. We demonstrate the sustained use of a SQUID amplifier operating between 812 and 860 MHz with a noise temperature of 1 K. The receiver has a noise equivalent power of View the MathML source in the band of operation for an integration time of View the MathML source.>>

<<ADMX converts axions to detectable microwave photons via the inverse Primakoff effect within a tunable,
high quality factor (Q ~ 50000) microwave cavity immersed in a strong magnetic field.>>

<<The ADMX detector consists of a 1-m tall, 0.5-m diameter, copper plated, stainless steel, right cylindrical
cavity kept at 1.8 K and placed in a 7.6 T magnetic field>>


We are missing the 7.6 T strong magnetic field in the Eagleworks experiment.  The only magnetic field is the one produced by the magnetic damper, which is there only by chance (mainly to dampen the swinging oscillations of the inverted pendulum and also the torsional oscillations).  The magnetic damper is located about a foot away from the tested microwave device (Cannae or Frustum).

Eagleworks has three Neodymium (NdFeB Grade N42) block magnets interacting with the pendulumís aluminum angle to dampen oscillatory motion.

For comparison, the magnetic field intensity at the surface of a neodymium magnet is 1.25 T

So would these 'dark matter axioms converted to microwave photons' result in net thrust...if that is what is going on? 

Offline Rodal

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Re: EM Drive Developments
« Reply #1103 on: 09/29/2014 03:42 AM »
dark matter?

Can't answer your question, they run at twice the frequency required, less than half the Q at Washington, and the main problem is that the magnetic field was ~1 T instead of ~7T, was there only by chance and too far away (a foot from the tested device).

Not really clear (even if axions do exist and if some interaction would take place) how would this generate propulsion.

We don't even know whether axions do exist.  They are trying to detect them at Washington.

As far-fetched as this would be, sounds certainly much more plausible than pumping the (dark energy) Quantum Vacuum... :)
« Last Edit: 09/29/2014 03:51 AM by Rodal »

Offline ThinkerX

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Re: EM Drive Developments
« Reply #1104 on: 09/29/2014 03:52 AM »
Quote

The interaction would be the other way around, photon interaction...

Ok, so microwave photons are creating (?) dark matter axioms?  (trying for clarity here, though this sounds a little like my earlier speculation)

Quote

Can't answer your question, they run at twice the frequency required, less than half the Q at Washington, and the main problem is that the magnetic field was there only by chance and far away (a foot from the tested device).

As far-fetched as this would be, sounds certainly much more possible than pumping the Quantum Vacuum...

Assume that by sheer chance if nothing else, the drive built and tested by the Eagleworks team is 'using microwave photons to create dark matter axioms,' which seems at least plausible as everything connected with dark matter has giant question marks attached.  If this is the case, then in your best view, would this qualify as a 'propellentless drive' or 'EM drive?'  And would we be in serious violation of the laws of physics here?




Offline frobnicat

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Re: EM Drive Developments
« Reply #1105 on: 09/29/2014 09:11 AM »
Quote

The interaction would be the other way around, photon interaction...

Ok, so microwave photons are creating (?) dark matter axioms?  (trying for clarity here, though this sounds a little like my earlier speculation)

Quote

Can't answer your question, they run at twice the frequency required, less than half the Q at Washington, and the main problem is that the magnetic field was there only by chance and far away (a foot from the tested device).

As far-fetched as this would be, sounds certainly much more possible than pumping the Quantum Vacuum...

Assume that by sheer chance if nothing else, the drive built and tested by the Eagleworks team is 'using microwave photons to create dark matter axioms,' which seems at least plausible as everything connected with dark matter has giant question marks attached.  If this is the case, then in your best view, would this qualify as a 'propellentless drive' or 'EM drive?'  And would we be in serious violation of the laws of physics here?

Dark matter is believed to be composed of real particles, WIMPs or axions. Various hypotheses for their parameters... ongoing experiments keep excluding more and more of the easiest (theoretically ? don't know for sure, experimentally for sure) parts of the parameter space (mass, electroweak coupling...). Ultra sensitive dedicated experiments have yielded no definitive answer so far (we would have heard about !) even if some candidate signals have been reported. Wimps would be high energy >>GeV while axions would be low mass (circa neutrinos or even bellow ?).

Speculations :

H1/ Given those scales if interaction with microwaves is possible it would need axions, not WIMPs.

H2/ I agree this would be much more plausible (as a source of thrust) than other more exotic explanations : even if unknown those would be real particles with real momentum to exchange with, within the formalism of relativistic QFT.

We need to discriminate two very different situations

S1/ Coupling a local RF field with existing axions that just happen to be there : pushing on the local dark matter. Since this matter is real but not interacting there is 0 chance that the average velocity of this "dark gas" is synchronised with rotating earth surface or even with earth centre of mass on its orbit around the sun. It is possible that this dark average velocity is in the same direction and grossly similar magnitude as solar system (sun) velocity orbiting the galaxy, but unknown for sure. What is certain is that in such a situation (coupling with existing dark matter) the device in a lab would see a strong relative wind of magnitude at least 30km/s (and possibly up to a few 100s km/s) with direction and exact magnitude depending of orientation to the stars (periodicity of 23 hours, 56 minutes sidereal time and day of the year (earth velocity on orbit around sun, relative to galactic referential). Will try to do some order of magnitude roughing to develop quantitatively this situation. Dr Rodal do you know of any attempt in the literature to characterize sidereal or year time periodicity of the various thrusters results ? That could explain why the results (if real) appear to be erratic...

S2/ Making (producing) axions in the device and letting them escape (undetected) in an asymmetric flow. If you want "no serious violation of the laws of physics" (even with unknown particle but still inside relativistic QFT framework) then this would be at best equivalent to a photon rocket (light particles with near c expelled velocity) or worse (heavy particles <<c) because of the higher energy to make real heavier particles (relative to the momentum benefit). So with axions it would be basically like making and expelling neutrinos, undetected or hard to detect jet, but still expelled mass_energy_momentum. Thrust/power on the order of 1/c at best. At least 2 orders of magnitude below the worst reported results (when non null results where reported).

Best

Offline frobnicat

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Re: EM Drive Developments
« Reply #1106 on: 09/29/2014 10:45 AM »

Ok, this is preliminary and difficult...
.../...
If all the signals are false, then there is no progress to be made by comparing the signals...


This is now several pages back but didn't want to leave it unchallenged -- frobnicat, it's not a detour for Eagleworks or Woodward to be focusing, decades into their separate work, building thrust levels as a primary focus compared to eliminating spurious, conventional sources of potential thrust. The fact is, the effort to eliminate spurious sources can go on forever if you are pumping hundreds of watts into a box and measuring micronewtons at a small distance above the noise threshold. In Woodward's case it's been over I believe 17 years of experiments.
But but but, if those thrust levels are false, I mean not about any backing theory but by the most basic experimental criteria : thrust/power > 1/c with no loss of mass (beyond the mass equivalence of energy involved) and not directly or indirectly pushing on a nearby ground. Those are exactly the conditions of applicability of the effect for space propulsion (and cheap energy generation BTW). This is the extraordinary experimental claim. I insist on the experimental aspect of it : possible backing theories are interesting, but need not be considered to discuss the practical implications of such experimental result, nor the methodology to ascertain the reality of the results (that is, it fulfils the above criteria). So for commodity what I call a false effect is a thrust or force that is not fulfilling those requirements, while a true effect does.

My point was, if measured forces are false effect then it is pointless to focus on devices with better thrust levels, unless very specifically this shows that the effect is false. For instance (excuse the cheap analogy, just to make my point clear) say some team of medieval scientists is interested in flying/hovering. They might note that jumping is a good start, gets them closer to the situation they want. But only for a limited amount of time. So they try to jump on a scale and measure the average weight. By integrating the weight over time they notice a small disparity of the average with the weight at rest. They deduce (posito quod deducunt ?) that a moving object has a different weight, on average, when compared to a resting mass. Now they will try to optimise the effect (lower average weight) by finding the best way to repetitively hop. They will likely succeed and getting better and better at having a lower average weight on the scale they will claim that surely there must be something since something is improving, so they are onto something. Looking at that with modern eyes we clearly see that this is a dead-end, they are only improving on exploiting some complex hard to understand measuring apparatus imperfection and coupling with varying weights, therefore improving on fooling themselves, as far as flying/hovering is concerned.

It will sound harsh and maybe unfair to put forward this cartoonesque analogy, given the genuine efforts of Woodward March et al for so many years. Even sceptics on this thread are convinced of the sincerity of those science adventurers and that we need people to take risks and explore unconventional things, otherwise we would not be discussing at length those results and theories, we wouldn't even care criticize.

Point is : " the effort to eliminate spurious sources can go on forever" will be the case if there is no true effect here, and we are just confirming the (expected) fact that it is just plain impossible, within ever better accuracy. Which is valid and interesting scientific progress : excluded at 300000/c, excluded at 1000/c, excluded at 1.0001/c ...  But then it would always be possible to say "this device is not producing thrust, but another one, backed by a better theory, could..." so yes it is endless, and will most likely be if no real effect is possible.

So before trying to improve thrusts levels of some design, please do the experiments in such a way that the effect has true meaning. If it is impossible (for budget/technical reasons) to get a clean yes/no answer to the question "is it real at all ?" then it is irrelevant (scientifically speaking) to get better thrusts and you would just be getting better at fooling yourself.

Being unable to build a consistent and reproducible experiment in 17 years is completely compatible with "no true effect is possible" or "true effect is possible but were never encountered yet", and less and less compatible with "some true effect was witnessed at some point". Regardless of priors and theories.

Quote
The one thing that changes the dynamic is if you can increase the thrust/power to the level where spurious sources of thrust are differentiated by the power level. The larger the thrust being measured, the easier it is to figure out the source.

So even if the theory is wrong, after so many years of chasing something uncertain, and if you're convinced either by the underlying theory or previous results, surely it makes sense to keep trying to increase the thrust while only slowly chipping away at the spurious potential sources.

If "my" theory is correct (true effect is impossible) : the thrust is spurious, trying to augment it is trying to augment a spurious effect. At some point it could appear clearly as spurious because it was augmented. Ok, I give you that. But it is also possible that in this antagonistic interplay between lowering the effects one recognize as spurious and augmenting the effects believed to be true (still spurious, but not recognized as such), and changing constantly from set-ups, devices, experimental conditions... one is just keeping on the level of confusion needed to maintain an illusion of true effect and progress when there is none.

So even if augmenting the thrust could be a way to find and understand it as a spurious effect (real progress) my take is that it is not the best way. Focus should be on a good appropriate balance and isolating the device, first, like Brito et al. Then if you have a positive result, this is a clean result, apply for Nobel. Else, null result (like Brito et al), this is also a clean result. Then try another theory/design. Don't expect better thrusting as any guideline for the new design as this is all or nothing, either you have a real effect (and improvement can come later, after the Nobel) or you have no real effect (and improving thrust is pointless). So every new design is a blank page.

Consider our medieval scientists, after some time at becoming expert at hoping on a given scale to optimise the averaged apparent weight they build a new and better scale. The experience gained in hoping to fool a mechanical scale is still useful to get non null result with the new model of scale, but not as good. Disparate results... but still non null, and still possible to refine the aptitude to fool this new kind of scale... (also at lower levels). Better and better scales, lower and lower effects, but still non null, and still possible to "improve" on any given scale. At some point a monk remarks that blowing downward has a very small but significant and continuous effect on apparent weight. That would be a real effect (for the goal of flying/hovering). What was gained in terms of progress by all those years of hoping when discovering this new real effect ? Better scales, I grant you that, but for the real effect it's like starting from a blank page.

This theory is falsifiable : show us a working reproducible effect fulfilling the requirements beyond any doubt. I'm not saying it would be easy (especially since I more and more believe this is impossible) but if it is possible, the methodology appears far from fundamental research standards. And I'm not the only one with this feeling. And a lot of them educated and usually open minded people won't even care sharing that thought but directly trash anything like "propellantless propulsion" in the abstract, not the least because the apparently poor methodology strategies and high confusion.

Best
« Last Edit: 09/29/2014 11:08 AM by frobnicat »

Offline frobnicat

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Re: EM Drive Developments
« Reply #1107 on: 09/29/2014 11:31 AM »
and to hit the nail on the experimental head :
The answer when asking about a clean null result is "oh yeah, but we have that theory (please read the book) that says that indeed this particular device shouldn't produce real thrust". Wait, what ? So the similar devices tested before that was reported as real results should have reported null ? Why they didn't ? And, if it proves impossible or too difficult to tell exactly why previous experiments reported positive as they should have reported null, what makes anyone believe that the new experiments with the new device from the new theory won't suffer from the same confusion between real and spurious results ?

How could a single result in years be true and not being amenable to a clean reproducible device ?
And if none of the result were true, how is the experimental situation different from a blank page ?
It would be if we were at least sure they were all null, at least it would be excluding some designs (smaller blank page) but this is not even the case...

« Last Edit: 09/29/2014 11:33 AM by frobnicat »

Offline frobnicat

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Re: EM Drive Developments
« Reply #1108 on: 09/29/2014 12:12 PM »
To sum up "what we want", or what mainstream scientists would expect (if any effect possible) :

(theory 1) device 1 -> ... clean null result
(theory 2) device 2 -> ... clean null result
(theory 3) device 3 -> ... unconclusive
(theory 4) device 4 -> ... clean null result
(theory 3) device 3 (+better instrumentation) -> ... clean null result
(theory 5) device 5 -> ... clean null result
...
(theory n) device n -> ... small but clean uncontroversial positive
-> Nobel
-> improve on device n
-> improve on theory n

Experimentally, each stage is blank page, the only progress is that the blank page is shrinking (clearly excluded designs). Sorry, this is not incremental (maybe for theory it could). This is all or nothing, hit or miss, and when missing there is no indication by how far. And there may be no target at all, be open for that. Obviously progress on instrumentation can be made incrementally, but not for the effect per se.

Teams times and budgets might make it hard to adhere to such an ideal scheme, that is understandable, but the observed deviations to orthodox methodology are way to important to give the subject the credibility it deserves "Because of the enormous commercial possibilities should it succeed".

Offline Rodal

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Re: EM Drive Developments
« Reply #1109 on: 09/29/2014 12:59 PM »

S1/ Coupling a local RF field with existing axions that just happen to be there : pushing on the local dark matter. Since this matter is real but not interacting there is 0 chance that the average velocity of this "dark gas" is synchronised with rotating earth surface or even with earth centre of mass on its orbit around the sun. It is possible that this dark average velocity is in the same direction and grossly similar magnitude as solar system (sun) velocity orbiting the galaxy, but unknown for sure. What is certain is that in such a situation (coupling with existing dark matter) the device in a lab would see a strong relative wind of magnitude at least 30km/s (and possibly up to a few 100s km/s) with direction and exact magnitude depending of orientation to the stars (periodicity of 23 hours, 56 minutes sidereal time and day of the year (earth velocity on orbit around sun, relative to galactic referential). Will try to do some order of magnitude roughing to develop quantitatively this situation. Dr Rodal do you know of any attempt in the literature to characterize sidereal or year time periodicity of the various thrusters results ? That could explain why the results (if real) appear to be erratic...


@frobnicat
Excellent analysis.  <<Coupling a local RF field with existing axions that just happen to be there : pushing on the local dark matter. >>  better explains the amount of thrust except for the problem of physical orientation of the thruster.  When Eagleworks turned the thruster device around by 180 degrees such that the ("Teflon") PTFE dielectric resonator was  oriented in the opposite direction, the measured thrust force also was in the opposite direction, so the thrust force followed the physical orientation of the thruster.

So, the thruster cannot be acting like the spinnaker on a sailboat, moving forward with the wind coming from its back, since in that case the boat could only move in the same direction as the wind, regardless of orientation of the boat. 

It would need to act more like a sailboat using its sail to go forward with the wind blowing at an angle against it.

This is possible in a sailboat because its sail is shaped like the wing of an airplane.  Wind blowing against the boat at an angle inflates the sail, and it forms an airfoil shape, creating a difference in pressure that pushes the sail perpendicular to the wind direction.

I have no idea what could be creating the "airfoil shape" in an EM thruster using dark matter.

I have to review again Dr. White's idea to "pump the quantum vacuum" but I recall it was akin to squeezing it  and using its expansion reaction to propel the spacecraft forward.  My recollection is that it did not see the quantum vacuum as a wind with a given direction.

Bottom Line: If Dark Matter's wind has a defined direction orientation, the only way that flipping the thruster around by 180 degrees could result in thrust in the opposite direction, with the thrust corresponding to physical orientation of the PTFE dielectric resonator is for the EM drive to be forming an airfoil shape to interact with the Dark Matter.  I do not see anything in the EM drive that would be forming such an airfoil shape. If we cannot come up with something in the EM drive that would be forming an airfoil shape, or if we don't conclude that Dark Matter is a directionless wind and the EM drive works by pumping the Dark Matter (as proposed by Dr White for the vacuum) then this possibility has to be discarded since it is nullified by the experiment.

If that would be the case we would be moving to consider possibility S2 for Dark Matter, where  <<Thrust/power on the order of 1/c at best. At least 2 orders of magnitude below the worst reported results>>.

Then this would be yet another explanation that produces by itself at least 2 orders of magnitude lower specific force,  and the measurements could be explained by self-excitation and mode coupling of the magnetically damped inverted pendulum.
 
« Last Edit: 09/29/2014 01:43 PM by Rodal »

Offline frobnicat

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Re: EM Drive Developments
« Reply #1110 on: 09/29/2014 01:41 PM »
.../...
It would need to act more like a sailboat using its sail to go forward with the wind blowing at an angle against it.
.../...
If we cannot come up with something in the EM drive that would be forming an airfoil shape, or if we don't conclude that Dark Matter is a directionless wind and the EM drive works by pumping the Dark Matter (as proposed by Dr White for the vacuum) then this possibility has to be discarded since it is nullified by the experiment.
.../...

A sail is a passive momentum exchange device : no input power from the ship. When considering a powered device the analogy would be more like a propeller : take the medium at a certain velocity vector and blow it on another velocity vector (magnitude and or direction). Some incoming relative speed wind effect could be smaller than the net thrust if exhaust speed is much higher. 20 km/h relative wind, forward or backward, relative to 400 km/h exhaust, would make only 10% difference. The reported thrust measurements (in "anomalous thrusts..." for instance) show some amount of disparity that could accommodate for this explanation up to a certain ratio... and indeed the ratio could be much lower as to be difficult to see at all. A scatterplot of enough data points, with magnitude against sidereal time could show such effect down to a certain threshold.

Quantitatively, the fact that direction reversal of thruster reverses thrust while keep roughly same magnitude (within what, 10% ?) would imply that the exhaust velocity of dark matter would be about 10 times higher than "dark matter wind" which in all likelihood is a least on the order of 30km/s -> more than 300km/s exhaust velocity. Got to check if it makes sense energetically. Also got to check if there is enough dark matter density to push onto. Quick search : this paper states about 1GeV/cm3. That sounds like not much. But no time to make quantitative argument right know, probably no posting for the next 48H.

Offline JasonAW3

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Re: EM Drive Developments
« Reply #1111 on: 09/29/2014 01:51 PM »
Guys,

Is it possible, that this device is somhow acting like and eductor type of device causing electrons to interact with dark matter, not so much as to push off from it, but to pull it along with itimparting more of a physical thrust?

  I imagine that there would be a fall off of effective kinetic energy from the electron stream produced as it interacts with the far heavier Dark Matter, but the overall effect may be sufficent to cause the observed effects.

I'm probably completely off base, but, it makes a whole lot more sense that "pushing off of Dark Matter"
My God!  It's full of universes!

Offline Rodal

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Re: EM Drive Developments
« Reply #1112 on: 09/29/2014 01:54 PM »
.../...
It would need to act more like a sailboat using its sail to go forward with the wind blowing at an angle against it.
.../...
If we cannot come up with something in the EM drive that would be forming an airfoil shape, or if we don't conclude that Dark Matter is a directionless wind and the EM drive works by pumping the Dark Matter (as proposed by Dr White for the vacuum) then this possibility has to be discarded since it is nullified by the experiment.
.../...

A sail is a passive momentum exchange device : no input power from the ship. When considering a powered device the analogy would be more like a propeller : take the medium at a certain velocity vector and blow it on another velocity vector (magnitude and or direction). Some incoming relative speed wind effect could be smaller than the net thrust if exhaust speed is much higher. 20 km/h relative wind, forward or backward, relative to 400 km/h exhaust, would make only 10% difference. The reported thrust measurements (in "anomalous thrusts..." for instance) show some amount of disparity that could accommodate for this explanation up to a certain ratio... and indeed the ratio could be much lower as to be difficult to see at all. A scatterplot of enough data points, with magnitude against sidereal time could show such effect down to a certain threshold.

Quantitatively, the fact that direction reversal of thruster reverses thrust while keep roughly same magnitude (within what, 10% ?) would imply that the exhaust velocity of dark matter would be about 10 times higher than "dark matter wind" which in all likelihood is a least on the order of 30km/s -> more than 300km/s exhaust velocity. Got to check if it makes sense energetically. Also got to check if there is enough dark matter density to push onto. Quick search : this paper states about 1GeV/cm3. That sounds like not much. But no time to make quantitative argument right know, probably no posting for the next 48H.

Well the propeller also has an airfoil shape (each blade of the propeller must be shaped like an airfoil), the difference, as you say being that the propeller is powered and not passive. The sail in a sailboat actually also needs some amount of human power and directional control (the sailor needs to constantly be controlling the force and trim of the sail).

 I don't see at the moment what could be giving an airfoil shape, and controlling the the airfoil, or as a set of moving airfoils as in a propeller. 

You are right that the propeller would make more sense since it is always fixed in the body (spacecraft or EM drive) direction, it does not need the human control attention that a sail needs.  The propeller better corresponds to the experimental findings of flipping the drive around by 180 degrees.

Unfortunately, I do not "see" the propeller in these EM drives.

Are you thinking of the photons inside the cavity ? or are you thinking of the PTFE dielectric resonator?

See you in 48 hours  :)
« Last Edit: 09/29/2014 02:36 PM by Rodal »

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #1113 on: 09/29/2014 01:55 PM »
You guys up there are great.  Even if you all are arcane, and subject to a mite too much dark hamster!  Still, your arguments can be followed.

Point is : " the effort to eliminate spurious sources can go on forever"

To continue with the analogy just for a bit, as the day goes by, the monks sweat, and they get lighter, increasing their hover time.  In addition, they also get tireder, decreasing their hover time.  There are many spurious forces that they must factor into their equations, as they attempt to improve their "thrust levels" as a means to proving their nascent theory.

The medieval scientist analogy is a good one.

Quote from: Frobnicat
If "my" theory is correct (true effect is impossible) : the thrust is spurious, trying to augment it is trying to augment a spurious effect. At some point it could appear clearly as spurious because it was augmented. Ok, I give you that. But it is also possible that in this antagonistic interplay between lowering the effects one recognize as spurious and augmenting the effects believed to be true (still spurious, but not recognized as such), and changing constantly from set-ups, devices, experimental conditions... one is just keeping on the level of confusion needed to maintain an illusion of true effect and progress when there is none.

... if it is possible, the methodology appears far from fundamental research standards

Which is the main point that Rodal has been hammering for many pages, to no acknowledgement. 

This is all or nothing, hit or miss, and when missing there is no indication by how far. And there may be no target at all, be open for that.

The analogy here is sighting in a new rifle/scope combo.  If you try it first at a hundred yards, you're not likely to hit the paper, therefore you don't know whether to adjust the scope up, down, left or right.  You have to tighten up the experimental apparatus by getting so close to the paper that you can't miss, then gradually backing off and verifying which direction the scope needs to be adjusted.

If, when you're close to the target, and you're still not making holes in the paper, you need to re-adjust your hypothesis completely.  Maybe you're firing blanks, not bullets, and it is not a scope adjustment issue at all.
Sometimes I just flat out don't get it.

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #1114 on: 09/29/2014 01:58 PM »
A sail is a passive momentum exchange device ...

Well the propeller also has an airfoil shape...

To continue with this line of reasoning over the next 48 Hamsters, consider making your "propellor" out of a magnetically induced force field.

I want to believe in the ether.
Sometimes I just flat out don't get it.

Offline Rodal

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Re: EM Drive Developments
« Reply #1115 on: 09/29/2014 02:02 PM »
Guys,

Is it possible, that this device is somhow acting like and eductor type of device causing electrons to interact with dark matter, not so much as to push off from it, but to pull it along with itimparting more of a physical thrust?

  I imagine that there would be a fall off of effective kinetic energy from the electron stream produced as it interacts with the far heavier Dark Matter, but the overall effect may be sufficent to cause the observed effects.

I'm probably completely off base, but, it makes a whole lot more sense that "pushing off of Dark Matter"

Sorry, I guess I'm not feeling that creative/imaginative in the morning.  I don't quite see something that could be acting like a "sail-like" airfoil, or a moving set of airfoils (a propeller) or an eductor type of device, in these EM drives.  Need some help from you to enable me to see these.

Furthermore, @frobnicat, @notsureofit and I have been discussing the photons of the microwave interacting with hypothetical (dark matter) axions (since at least the frequency of the microwave is in the right neighborhood for this, see my earlier post).

I don't understand where are the electrons coming from when you state <<causing electrons to interact with dark matter>>  are you thinking of field emission of electrons from a cracked PTFE dielectric resonator?

And why do you think that electrons in these microwave devices makes a whole lot more sense than photons to interact with (Dark Matter) axions?  Look at this : http://forum.nasaspaceflight.com/index.php?topic=29276.msg1263849#msg1263849

Sorry, I need some more coffee to wake up, I may be the one completely off base  :)
« Last Edit: 09/29/2014 03:14 PM by Rodal »

Offline Rodal

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Re: EM Drive Developments
« Reply #1116 on: 09/29/2014 03:16 PM »
A sail is a passive momentum exchange device ...

Well the propeller also has an airfoil shape...

To continue with this line of reasoning over the next 48 Hamsters, consider making your "propellor" out of a magnetically induced force field.

I want to believe in the ether.

Hey kernosabe, I came up with some numbers here http://forum.nasaspaceflight.com/index.php?topic=29276.msg1263849#msg1263849

Please give us your numbers for your ether magnetically induced force field  :)

You also get 48 Hamsters-Hours to provide those numbers.  If you do you get a drink.
« Last Edit: 09/29/2014 03:17 PM by Rodal »

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Re: EM Drive Developments
« Reply #1117 on: 09/29/2014 04:06 PM »
I want to believe in the ether.

Hey kernosabe, I came up with some numbers here http://forum.nasaspaceflight.com/index.php?topic=29276.msg1263849#msg1263849

Please give us your numbers for your ether magnetically induced force field  :)

You also get 48 Hamster-Hours to provide those numbers.  If you do you get a drink.

Ok.  How about Numbers 6:24-26?

Sadly, you ask for that which I cannot provide.  I want to believe in the ether, but it is not a fundamental need for me.  I guess it is my intuition which suggests that information can travel instantaneously, and also that there ought to be an instantaneous explanation for inertia.

The mental image of a spaceship using an "invisible" propeller shaped force field pushing against the "invisible" ether is an intriguing one for me.

You had mentioned considering a 24 hour fluctuation in the "Force" as a means of determining the direction of the "inertial wind".  Might I also throw out this paper, regarding the idea that there is change in the gravitational constant?

What is the nature of the liquid drink that you suggest?
« Last Edit: 09/29/2014 04:07 PM by JohnFornaro »
Sometimes I just flat out don't get it.

Offline Rodal

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Re: EM Drive Developments
« Reply #1118 on: 09/29/2014 04:16 PM »
I want to believe in the ether.

Hey kernosabe, I came up with some numbers here http://forum.nasaspaceflight.com/index.php?topic=29276.msg1263849#msg1263849

Please give us your numbers for your ether magnetically induced force field  :)

You also get 48 Hamster-Hours to provide those numbers.  If you do you get a drink.

Ok.  How about Numbers 6:24-26?

Sadly, you ask for that which I cannot provide.  I want to believe in the ether, but it is not a fundamental need for me.  I guess it is my intuition which suggests that information can travel instantaneously, and also that there ought to be an instantaneous explanation for inertia.

The mental image of a spaceship using an "invisible" propeller shaped force field pushing against the "invisible" ether is an intriguing one for me.

You had mentioned considering a 24 hour fluctuation in the "Force" as a means of determining the direction of the "inertial wind".  Might I also throw out this paper, regarding the idea that there is change in the gravitational constant?

What is the nature of the liquid drink that you suggest?

Hey kernosabe!

What do you know, the paper is from my alma mater , and the pendulum is a classical Cavendish type pendulum (just as used by Brito, Marini and Galian to nullify the Woodward MLT drive and used in classical experiments of inverse square law gravitation and measurement of the Casimir force) instead of that nonlinearly-coupled magnetically damped inverse pendulum.

Again: #1 priority is to replicate the Eagleworks experiments at John Hopkins using their Cavendish.

Good ol' Cavendish http://en.wikipedia.org/wiki/Cavendish_experiment  performed his experiment in 1797, 217 years ago, and he was capable of measuring a force of  0.174 microNewtons, less than 1% of the reported thrusts at Eagleworks.   

By comparison, the admitted magnetic interaction in the magnetically damped inverted pendulum at Eagleworks was ~10 microNewtons (and I think it is substantially more because of nonlinear coupling not taken into account). That's ~55 times greater than Cavendish.

Go back to the classics  :)

Oh, and the drink is a Martini

« Last Edit: 09/29/2014 04:34 PM by Rodal »

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Re: EM Drive Developments
« Reply #1119 on: 09/29/2014 04:28 PM »
Oh, and the drink is a Martini.

Huh.  Shaken or stirred?

There's also this paper:
Sometimes I just flat out don't get it.

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