Author Topic: EM Drive Developments Thread 1  (Read 1473110 times)

Offline frobnicat

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Re: EM Drive Developments
« Reply #3140 on: 11/11/2014 06:28 pm »


The test campaigns are discussed in the video too.

@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!

NASA Ames Research Director’s Colloquium, August 12, 2014.

discusses Infrared camera image of the Cannae test article at @36 minutes

Of course, as posted previously, there is no heating of the exterior round lateral surface of the cone.
White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.

What we see on the IR picture is the Cannae where there is no low thermal conduction PCB plate involved...

And even on this mostly copper apparatus we see not a lot of heat going out, "because it's High Q". But high Q or not, driven at resonance or not, power pumped in frustum should be dissipated from frustum. The RF amplifier heats a lot (comparatively). I don't find again the actual values of power injected for Cannae, nor the value of power injected to amplifier (as DC current of 5.6 A). I get that the RF amplifier has a limited efficiency (how much ?) and delivers less in microwave watts than it takes in DC watts, that would account for such a disparity in dissipated power from RF amplifier relative to frustum ? What when the RF power is less (like 2.6 W) : the amplifier eats less DC ( I remember someone told it was class AB...) or dissipates more (like a class A that takes as much power input, whether outputting AC or not) ?

My doubt : is the microwave power (indicated as reference for all the experiments, like 16.9 W ...) really pumped in the cavity "one way" or isn't a large part of this power bouncing back at the RF amplifier and being dissipated there, making for a lower net power input to cavity ? Opinions from people knowing RF circuits and microwave generators better ?

Offline Mulletron

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Re: EM Drive Developments
« Reply #3141 on: 11/11/2014 06:38 pm »


The test campaigns are discussed in the video too.

@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!

NASA Ames Research Director’s Colloquium, August 12, 2014.

discusses Infrared camera image of the Cannae test article at @36 minutes

Of course, as posted previously, there is no heating of the exterior round lateral surface of the cone.
White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.

What we see on the IR picture is the Cannae where there is no low thermal conduction PCB plate involved...

And even on this mostly copper apparatus we see not a lot of heat going out, "because it's High Q". But high Q or not, driven at resonance or not, power pumped in frustum should be dissipated from frustum. The RF amplifier heats a lot (comparatively). I don't find again the actual values of power injected for Cannae, nor the value of power injected to amplifier (as DC current of 5.6 A). I get that the RF amplifier has a limited efficiency (how much ?) and delivers less in microwave watts than it takes in DC watts, that would account for such a disparity in dissipated power from RF amplifier relative to frustum ? What when the RF power is less (like 2.6 W) : the amplifier eats less DC ( I remember someone told it was class AB...) or dissipates more (like a class A that takes as much power input, whether outputting AC or not) ?

My doubt : is the microwave power (indicated as reference for all the experiments, like 16.9 W ...) really pumped in the cavity "one way" or isn't a large part of this power bouncing back at the RF amplifier and being dissipated there, making for a lower net power input to cavity ? Opinions from people knowing RF circuits and microwave generators better ?

The point of a well engineered rf system is to keep forward power high and reflected power low. This is evidenced by using a dual port directional coupler with fwd/reflected power sample ports tied to power meters so you can tune your device to keep reflected power from going back into your amp/sig gen/whatever. This is called VSWR and is a ratio. So the rf energy going into the cavity will eventually be absorbed by the cavity as a function of Q and be converted to heat. You would never want your power to be reflected back into your signal generating gear. This stuff is my day job.
« Last Edit: 11/11/2014 06:43 pm by Mulletron »
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Offline Rodal

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Re: EM Drive Developments
« Reply #3142 on: 11/11/2014 07:25 pm »


The test campaigns are discussed in the video too.

@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!

NASA Ames Research Director’s Colloquium, August 12, 2014.

discusses Infrared camera image of the Cannae test article at @36 minutes

Of course, as posted previously, there is no heating of the exterior round lateral surface of the cone.
White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.

What we see on the IR picture is the Cannae where there is no low thermal conduction PCB plate involved...

.....

Thank you for emphasizing that.

The COMSOL FE analysis shows the electric field in the dielectric (Teflon PTFE) to be 20 to 50 times higher than elsewhere in the Cannae.

However both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are non-polar, hence no dipole microwave heating can take place unless they contain some water molecules.

PTFE ("Teflon") is also hydrophobic so not likely to contain water molecules and hence very unlikely to be microwave heated.

Both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are also dielectric-heat-transparent to RF frequencies so negligible dielectric heating in them as well.

So if there is any internal heating in the Cannae it must be the result of the electromagnetic field on the copper.  Unfortunately the magnetic field is not shown.  So no further comments on this unless we analyze the magnetic field in the Cannae, to see whether the dielectric polymer plug is in the way of a magnetic axial field. 

There are questions as to what is the use of the "pillbox" in the Cannae design as brought up by Mulletron and by White.
« Last Edit: 11/11/2014 07:34 pm by Rodal »

Offline birchoff

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Re: EM Drive Developments
« Reply #3143 on: 11/11/2014 07:32 pm »


The test campaigns are discussed in the video too.

@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!

NASA Ames Research Director’s Colloquium, August 12, 2014.

discusses Infrared camera image of the Cannae test article at @36 minutes

Of course, as posted previously, there is no heating of the exterior round lateral surface of the cone.
White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.

What we see on the IR picture is the Cannae where there is no low thermal conduction PCB plate involved...

.....

Thank you for emphasizing that.

The COMSOL FE analysis shows the electric field in the dielectric (Teflon PTFE) to be 20 to 50 times higher than elsewhere in the Cannae.

However both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are non-polar, hence no dipole microwave heating can take place unless they contain some water molecules.

PTFE ("Teflon") is also hydrophobic so not likely to contain water molecules and hence very unlikely to be microwave heated.

Both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are also transparent to RF frequencies so negligible dielectric heating in them as well.

So if there is any internal heating in the Cannae it must be the result of the electromagnetic field on the copper.  Unfortunately the magnetic field is not shown.  So no further comments on this unless we analyze the magnetic field in the Cannae.

If I understand what you said. and the IR camera image from the presentation is not faked. Wouldn't that put a nail in the coffin of thermal effects artifact? At least as far as the Cannae testing is concerned.

Offline birchoff

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Re: EM Drive Developments
« Reply #3144 on: 11/11/2014 07:37 pm »

The test campaigns are discussed in the video too.

@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!

I think the most interesting thing in this entire presentation for me was the elaboration of the next steps. Assuming they wait until after all of the Eagleworks portion of the next steps is done to publish another paper. I suspect there should be more than enough information at that point to know if this is a real effect or not. Especially if they are actually able to run a Null configuration of their thruster in vaccum.

Secondarily, prior to the Q-Thruster testing summary. It looks like White is pushing on with his Warp drive experiments. Wish him the best of luck. Though I am most skeptical as it seems like if the Q-Thruster stuff is shown to not be a real effect but something classical, like Heat or Magnetic coupling. Then he would have no way to justify that any artifacts observed by his interferometer was caused by space warping.

Offline Rodal

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Re: EM Drive Developments
« Reply #3145 on: 11/11/2014 07:40 pm »


The test campaigns are discussed in the video too.

@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!

NASA Ames Research Director’s Colloquium, August 12, 2014.

discusses Infrared camera image of the Cannae test article at @36 minutes

Of course, as posted previously, there is no heating of the exterior round lateral surface of the cone.
White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.

What we see on the IR picture is the Cannae where there is no low thermal conduction PCB plate involved...

.....

Thank you for emphasizing that.

The COMSOL FE analysis shows the electric field in the dielectric (Teflon PTFE) to be 20 to 50 times higher than elsewhere in the Cannae.

However both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are non-polar, hence no dipole microwave heating can take place unless they contain some water molecules.

PTFE ("Teflon") is also hydrophobic so not likely to contain water molecules and hence very unlikely to be microwave heated.

Both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are also transparent to RF frequencies so negligible dielectric heating in them as well.

So if there is any internal heating in the Cannae it must be the result of the electromagnetic field on the copper.  Unfortunately the magnetic field is not shown.  So no further comments on this unless we analyze the magnetic field in the Cannae.

If I understand what you said. and the IR camera image from the presentation is not faked. Wouldn't that put a nail in the coffin of thermal effects artifact? At least as far as the Cannae testing is concerned.

Well, I had said no further comments on this, but since you ask ... :)

I think (but I would need to analyze this to be sure) that there is an axial magnetic field through the axis of the Cannae, while the electric field is rotationally transverse, as in the TE012 mode of a cylinder.  If this is the case, the dielectric polymer could be blocking the magnetic field heating of the copper in the long end of the Cannae.  (Unfortunately White did not provide the magnetic field for the Cannae and he did not provide the dimensions of the Teflon plug or the internal dimensions of the Cannae long section and how the dielectric fits inside it (how snug is it?)

No nail in the coffin but certainly the Cannae would require much more analysis to show it as a thermal artifact as compared to the truncated cone where I have preliminary numbers showing the initial impulse to be due to internal heating of the copper at the big diameter flat end.
« Last Edit: 11/11/2014 07:45 pm by Rodal »

Offline aceshigh

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Re: EM Drive Developments
« Reply #3146 on: 11/11/2014 09:04 pm »
He answers that the Alcubierre drive doesn't violate causality and that it cannot be used for time travel to the past because the spacecraft never travels faster than the speed of light in its local spacetime.

I remember an astrophysicist friend of mine and other people at physics forums saying that no matter if the local spacetime didn't change (warp) or you got instantaneously from one point to another (warp), it was still time travel to the past, because of the light cone or something like that. Any opinion Dr Rodal?

Offline frobnicat

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Re: EM Drive Developments
« Reply #3147 on: 11/11/2014 09:14 pm »
.../...
Both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are also transparent to RF frequencies so negligible dielectric heating in them as well.

So if there is any internal heating in the Cannae it must be the result of the electromagnetic field on the copper.  Unfortunately the magnetic field is not shown.  So no further comments on this unless we analyze the magnetic field in the Cannae.

If I understand what you said. and the IR camera image from the presentation is not faked. Wouldn't that put a nail in the coffin of thermal effects artifact? At least as far as the Cannae testing is concerned.

Obviously it would be difficult to definitely prove thermal effects artefacts as the main contributor to the reported thrust, at a distance from the experiment and given the sparse published information. What I'm confident we can do (on spare time...) even at amateur level (serious amateur level) is bring forward possible thermal modes of "failure", maybe in qualitative agreement (parameters dependencies the right way) and roughly quantitative agreement with what is published : if such is the case, that would not prove definitely the results as being thermal in origin but would require experimenters (or preferably third parties) to see in-situ that it is not thermal as hypothesized by the amateurs...

The authors have been fast at dismissing the possible thermal effects and to answer remarks on the subject. The IR picture is showing that they are thinking about it and making real effort on this (as I guess that is one of the most common doubt raised on their experimental results, beyond theoretical scepticism) but the impression is that they give too much credit to the steepness of their step response so that "it surely can't be thermal, or not all thermal" as common sense would tell "because thermal would be too slow for such a step response".

For instance (that's my working hypothesis at the moment), air has a very low thermal capacity but can give high forces with very modest heat energies basically through pV = nRT. Air temperature don't really show up in the IR picture. A one °C in a closed cavity will give 10s of pascals differential pressure buildup, 10N/m² that's more than .1N differential between small end and big end and we are measuring 10s of µN so this is 4 orders of magnitude less. Granted : if the cavity is perfectly hermetic this pressure buildup can't really make any net thrust. But the slightest leak, especially the slightest leak, will jet this modest overpressure enough to make the relevant µN magnitude.

If there are big holes, like vents in a microwave oven, no pressure buildup, no efficient jet. If there are no holes at all, no jet. That would need a clarification from the experimenters : are the cavity perfectly hermetic or not. And if they are not, what is the path the air is taking to equilibrate to ambient. The fact that removing a dielectric plug in the Cannae makes thrust plummet would be in agreement with that : the leak path would become too big to make an efficient nozzle.

If humidity of air is enough to couple with high energy density standing waves (high Q...) there is instantaneously a constant rate of dT/dt, and it don't take much time for a pressure buildup and reaching a plateau of thrust from a "warm" air jet escaping the cavity. Hence a steplike response. But I'm stuck with this question of the volumetric heating of ordinary lab air (30% to 70% relative I guess) by "high Q microwaves" (by that I mean that even a high transparency material relative to microwaves still has a chance to couple with some amount of power). This would probably be a very simple question to answer for some specialist.

So for instance, there is no nail in the coffin of this idea before the questions of air leaks and volumetric air heating are settled.

Offline Rodal

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Re: EM Drive Developments
« Reply #3148 on: 11/11/2014 09:34 pm »
He answers that the Alcubierre drive doesn't violate causality and that it cannot be used for time travel to the past because the spacecraft never travels faster than the speed of light in its local spacetime.

I remember an astrophysicist friend of mine and other people at physics forums saying that no matter if the local spacetime didn't change (warp) or you got instantaneously from one point to another (warp), it was still time travel to the past, because of the light cone or something like that. Any opinion Dr Rodal?
I agree with the astrophysicist friend of yours that if the Alcubierre superluminal warp vehicle would be possible it could also act as a time machine because it distorts the spacetime around the spacecraft, and therefore time-loops are possible (regardless of the actual internal local speed of the spacecraft)  but I'm not interested in engaging into a long multi-post argument with anybody that agrees with Dr. White, as I don't think this thread is the proper place to have such time-travel arguments.

I have seen this stuff debated by others.  What most physicists (including Alcubierre himself) agree with (except apparently Dr. White and a few others including a Portuguese scientist),  is that the Alcubierre drive is not practically feasible and that wormholes remain as the only way to possibly ever travel superluminally.  I haven't watched the movie "Interstellar" yet  :)



« Last Edit: 11/11/2014 09:47 pm by Rodal »

Offline aceshigh

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Re: EM Drive Developments
« Reply #3149 on: 11/11/2014 09:46 pm »
João Magueiro?

Offline ThinkerX

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Re: EM Drive Developments
« Reply #3150 on: 11/11/2014 11:52 pm »
Quote
I have seen this stuff debated by others.  What most physicists (including Alcubierre himself) agree with (except apparently Dr. White and a few others including a Portuguese scientist),  is that the Alcubierre drive is not practically feasible and that wormholes remain as the only way to possibly ever travel superluminally.  I haven't watched the movie "Interstellar" yet  :)

Doctor McCulloch (MiHsC) claims his theory offers a super-luminal possibility, though the details are beyond me (as is much else).

As to 'Interstellar': overly long, badly flawed in places (you WILL want to launch the organ into space) but it did pay a fair bit of attention to the science, including some of the stranger effects possible with worm holes, time dilation, and what might as well be...hmmm...best leave that out. 

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #3151 on: 11/12/2014 02:03 pm »
Fun to play around with:
http://amrita.vlab.co.in/?sub=1&brch=280&sim=1518&cnt=4

Nothing is suspended from a wire:

Quote from: Brady, March, White, et.al.
The pendulum arm pivots about two linear flexure bearings in a plane normal to gravitational acceleration. The flexure bearings provide an essentially-frictionless and hysteresis-free interface between the static test stand fixed structure and the dynamic pendulum arm. Test article force is measured by measuring the pendulum arm displacement and calculating the force via the flexure bearing spring constants that were determined during test facility setup

NASA Eagleworks has an inverted pendulum.

According to Paul March, NASA Eagleworks uses as a torsional spring two Riverhawk C-flex bearing blocks with torsional spring constant


(http://flexpivots.com/cantilevered-single-ended-pivot-bearings/) centered 2.38" above and below the centerline of the 24.00" long by 1.50" Faztek aluminum pendulum arm. The long end of the pendulum arm is 15.5" from the torque pendulum's center of rotation, which makes the other short-end of the pendulum arm 8.5" from the center of rotation. 

However, the NASA report shows a linear flexure bearing  http://flexpivots.com/linear-flexure-bearing/

Well, the pic shows the bearing block anyway, not necc the c-flecs  (always used c-flex me self back then)

So, who are we to believe you think based on your experience and looking at the picture?  (Honest question, not a trick question)

The report that states linear bearing or Paul March that stated C-Flex bearing?
It is indeed a C-Flex torsion balance.  I think calling it "inverted" is causing more trouble than it's solving.  This is the design used by Woodward, who was the first to put the liquid metal contacts in, and adopted by him in 2005 from the Austrian Research Center who has been running one for more than a decade.  It was in light of this Woodward named his balance the "ARC Lite" but it turns out, ARC did not invent the balance either.  It was in service at UCLA before this and several other places, and is certainly the most precise balance design to date.  Suspension balances suffer different issues, so it is a toss up which is better, but the torsion balance is certainly more accurate as it has nN resolution and can carry a great deal of mass and retain that resolution.

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #3152 on: 11/12/2014 02:10 pm »
@Rodal - Did you write that the side walls of the cone are not subject to heating?

Because if the side walls did warm the outside boundary layer of air then the warmer boundary layer would rise causing a reduced pressure over the outside of the cone walls. The result would be a net force toward the small end.
The balance design unfortunately does suffer some small amount of vertical to horizontal coupling as changes in vertical force can show up as small horizontal thrusts.  This is one reason why Woodward's balance (and one supposes the one at Eagleworks) includes the ability to physically reorient the thruster to point left and right, so that sort of coupling can be subtracted out as common noise.  Precise explanations of this out ought to appear in any peer review lit that eventually comes from Eagle.

Offline Rodal

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Re: EM Drive Developments
« Reply #3153 on: 11/12/2014 02:50 pm »
@Rodal - Did you write that the side walls of the cone are not subject to heating?

Because if the side walls did warm the outside boundary layer of air then the warmer boundary layer would rise causing a reduced pressure over the outside of the cone walls. The result would be a net force toward the small end.
The balance design unfortunately does suffer some small amount of vertical to horizontal coupling as changes in vertical force can show up as small horizontal thrusts.  This is one reason why Woodward's balance (and one supposes the one at Eagleworks) includes the ability to physically reorient the thruster to point left and right, so that sort of coupling can be subtracted out as common noise.  Precise explanations of this out ought to appear in any peer review lit that eventually comes from Eagle.

Rather than arguing about what something should be called (whether this balance should be called inverted or something else -it is an undeniable fact that it has a stiff flexural vertical components-) scientists proceed with analytical models of the testing equipment they use.  This is the case at CERN, and it is the case for Physics and Engineering thesis at MIT: all experimental work should be accompanied by analytical models of the testing equipment. 

With Mathematica I have modeled the full system of coupled nonlinear differential equations for the Eagleworks balance.  I am not aware of Eagleworks having conducted similar analytical models (coupled nonlinear differential equations) of their testing equipment. 

The reason why I modeled the full system of coupled differential equations for their testing equipment was both that I had the ability to do so (from my prior professional experience) and also because of my professional curiosity.  There are quite a number of studies at MIT on testing equipment and balances of different types to study electric propulsion and other forms of propulsion.  It is known that due to the thrusters exhibiting a wide frequency spectrum, that parasitic, Duffing, Hill equation, and many other forms of nonlinear vibration can take place due to self-excitation, coupling, and nonlinearities in general.  Without an analytical model one cannot dismiss outright these effects from taking place. 

So, I modeled the testing equipment in case the thruster would exhibit high frequency components.  What do I see from running the model? The same thing I (and Frobnicat among others) see from looking at the response: it is behaving as a simple horizontal torsional pendulum.  There are no high frequency components, no nonlinearities. No self excitation.  So, for the exhibited response of this thruster so far at Eagleworks, I have no problem in calling this a simple horizontal torsional pendulum.   The lack of excitation of higher frequencies, is not just a characteristic of the testing equipment, it is also a characteristic of the tested thruster.  This is what's important here, something that frobnicat with his experience in dynamics has also noticed: this thruster is not exhibiting a complex high-frequency response.  The pendulum arm (only 1.5 inch by 1.5 inch aluminum Faztek, which is not rigid by any consideration) frequency is not being excited.  No higher mode excitation.   

It does behave as a microwave heater attached to a horizontal torsional pendulum:

The Fourier Transform analysis I conducted shows practically nothing with period less than 2 seconds.  Nothing.  Nada.

The autocorrelation analysis I posted shows a boring simple harmonic response.  No random excitation. None.  Nada.

The amplitude response vs. time does not indicate it either.

This shows me that there is nothing anomalous about the response of the truncated cone: it is most probably due to thermal effects.   Even a chemical thruster exhibits complex response.  This is not the case here.  As frobnicat pointed out there is a huge amount of effort in trying to see the effects of the Quantum Vacuum and not enough effort to try to see the effect of classical physics.
« Last Edit: 11/12/2014 03:21 pm by Rodal »

Offline D_Dom

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Re: EM Drive Developments
« Reply #3154 on: 11/12/2014 03:18 pm »
This shows me that there is nothing anomalous about the response of the truncated cone: it is most probably due to thermal effects.   Even a chemical thruster exhibits complex response.  This is not the case here.

Thanks for your efforts investigating this experiment. As I understand what you are saying (which is not much ) thermal effects create none of the complex response normally found in a chemical or electric thruster.

Page after page of this discussion have me convinced that I will take some time, visit the links, work some equations and generate an understanding of the topic. Thanks for explanations that seem within reach though I am not yet able to grasp.

Space is not merely a matter of life or death, it is considerably more important than that!

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #3155 on: 11/12/2014 03:57 pm »
. . .all experimental work should be accompanied by analytical models of the testing equipment.

. . .As frobnicat pointed out there is a huge amount of effort in trying to see the effects of the Quantum Vacuum and not enough effort to try to see the effect of classical physics.

It took the guys at Eagle a couple years to characterize the new balance. Normally it takes about a year but they had trouble with coupling to the stainless tank, which is common for this kind of setup.  George Hathaway documents this kind of struggle somewhere on the web and it took his lab up in Canada more than a year to solve the coupling issue.  Woodward took far less time because he uses acrylic so there's less opportunity for high voltage to couple.  Personally I think the best compromise is polycarbonate like Lexan since it has a lower vapor pressure than acrylic so one can pull harder vacuum.  I think Woodward can only pull E-3T and Lexan can provide E-5T.  I would just note to those who always want to see E-12T, that if you don't see a source scale at ambient to E-3T, you know you don't have things like thermal and ionic wind, so it is a poor trade to spend an extra $100k to the vacuum system, and an extra year characterizing the setup, just to have harder vacuum.  IMHO, leave the hard vacuum for those doing validation studies who already have such things available.  Clear is also nice in that your thermal sensing and doppler vibrometer can have easy access without going inside the chamber.

I think you're again mistaking your resource.  I will remind you again, you are analyzing a CONFERENCE PAPER.  It is not normal to put the kinds of detail into a conference paper that you are complaining are missing.  You are doing analysis that is quite impressive, but you are working without the real details because you are working from a conference paper. 

IMHO, if Eagle can get other NASA centers to investigate this without publishing in peer review, this is likely what they will do.  Sonny has always shied away from careful inspection of his work.  I see no reason for him to publish in peer review when he can get 3 other NASA centers to go after validation without risking anything.  He's very shrewd that way.
« Last Edit: 11/12/2014 04:04 pm by Ron Stahl »

Offline Rodal

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Re: EM Drive Developments
« Reply #3156 on: 11/12/2014 04:10 pm »
....I see no reason for him to publish in peer review when he can get 3 other NASA centers to go after validation without risking anything.  He's very shrewd that way.

When you write " to go after validation without risking anything.  He's very shrewd that way" I don't understand what is not being risked and why is this being "shrewd".

A scientist wants as much peer review as he can get.  You want to publish in peer review journals.  It  is to your own benefit. If you are correct you get the recognition.  If you are incorrect the sooner you find out the better.  If others point out that you are missing something it is to your benefit. If one doesn't get peer review and discussion with other scientists, then one really may end up wasting precious years of your life in the wrong path and not really learn anything.

Quote from:  Benjamin Franklin
Lost time is never found again.


« Last Edit: 11/12/2014 04:14 pm by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #3157 on: 11/12/2014 05:23 pm »
When you write " to go after validation without risking anything.  He's very shrewd that way" I don't understand what is not being risked and why is this being "shrewd".

A scientist wants as much peer review as he can get.  You want to publish in peer review journals.  It  is to your own benefit. If you are correct you get the recognition.  If you are incorrect the sooner you find out the better.  If others point out that you are missing something it is to your benefit. If one doesn't get peer review and discussion with other scientists, then one really may end up wasting precious years of your life in the wrong path and not really learn anything.

In my experience, Sonny has always taken the path of least resistance.  I don't know if he's ever published in peer review and in fact, doing so is problematic since ZPF and QVF are not well liked in the journals.  When Sonny went to do his doctoral thesis, he was denied use of his QVF model since it is not the stuff physicists want to waste time with.

I do however agree with your point.  I'm just answering your question.

What you might do if you want more detail on the balance, is contact Dr. Duncan Cummins (PhD Oxford? or Cambridge?--I often confuse them), who runs the little Stardrive group that did some analysis on the Eagle balance when it was being characterized.  Duncan is a skeptic who thinks this stuff is all naive, but he runs the little yahoo group that looks into these things.  IIUC, Paul March and Sonny are both a part of that group, as is Andrew Palfreyman (also Oxford, unless I'm confusing it with Cambridge again) and David Mathes of CalTech.  It was Duncan who said to me back in May or so that Eagle had had lots of signal until they grounded the balance properly and then it all went away.  Don't think that's really true but you could ask him.  He'd probably be thrilled to have someone with your skills and experience commenting in his group.

[email protected]

And about the shrewdness thing. . .it is good to note that without publishing in peer review and putting out all the work this entails, Sonny has managed not only to redirect substantial NASA resources and DARPA funding onto his project, but now several NASA centers will be pursuing it.  That is at the least, highly efficient, and he still hasn't stuck his neck out for his QVF model.  That's more than shrewd.  It's clever even.  I'm not suggesting this is how science should be done, but he is getting what he wants.  The trouble is, that eventually everyone will figure out the truth of the issue and the consequences of that will be interesting to say the least.
« Last Edit: 11/12/2014 05:56 pm by Ron Stahl »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #3158 on: 11/12/2014 06:07 pm »
Here's a pic on the web of Woodward's torsion balance, the "ARC Lite".  The thruster is in a squarish Faraday cage on the right.  This is out of the chamber for some sort of work, so things like the cable draped over on the left are out of place.  Note the coaxial liquid metal contacts centered over the torsion bearing at center, the aluminum damper at left, and at lower right the open coils used to calibrate the balance.  I expect this is how the Eagle balance works as well.  You just can't see much of it from the Eagle pics.

http://nextbigfuture.com/2011/06/james-woodward-reports-consistent-and.html

Would that we could see some of this same level of investigation of Woodward's data.  Personally I am more impressed with the analysis here in this thread than that at NASA, even by folks like Creon Levit.  If Dr. Rodel, you want to offer your services to do analysis for Levit, let me know and I'll send a private link.

can you tell me, where I would find more folks able to do the level of analysis you've been doing in this thread--someone to lead an exploration into M-E physics?
« Last Edit: 11/12/2014 06:21 pm by Ron Stahl »

Offline birchoff

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Re: EM Drive Developments
« Reply #3159 on: 11/12/2014 08:48 pm »
...

And about the shrewdness thing. . .it is good to note that without publishing in peer review and putting out all the work this entails, Sonny has managed not only to redirect substantial NASA resources and DARPA funding onto his project, but now several NASA centers will be pursuing it.  That is at the least, highly efficient, and he still hasn't stuck his neck out for his QVF model.  That's more than shrewd.  It's clever even.  I'm not suggesting this is how science should be done, but he is getting what he wants.  The trouble is, that eventually everyone will figure out the truth of the issue and the consequences of that will be interesting to say the least.

So maybe I am missing something, but if I take what your saying here at face value. The conclusion I am forced to draw is the scrutiny the NASA labs will do of White's QVF model will be significantly less than if he had attempted to get it into a peer review journal. Am I the only one that finds this to be a weird conclusion. Shouldn't labs be doing an equivalent level of review of another teams work before taking on the job of doing validation. At the very least I would hope that the validation is at least required to do more than simply taking the assembled equipment from EagleWorks and running it in a different geographical location.

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