Author Topic: EM Drive Developments Thread 1  (Read 1472569 times)

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #1660 on: 10/07/2014 02:44 pm »
Given Woodward's assertions about exciting an oscillation in a dielectric and then pushing on it at an opportune time to move forward clearly does violate conservation of momentum.

If I'm not gravely mistaken, Woodward's theory is supposed to involve excitation of mass fluctuations much larger than the E/cē you'd calculate from the local electromagnetics, via gravitational interaction with distant matter.  It's supposed to conserve momentum via that same interaction.

Mulletron does not seem to acknowledge the "gravitational interaction with distant matter" part.  In fact, that has not yet been discussed all that much (or at least to my satisfaction and education).  "That" being, the definition of inertia thing suggested by Mach and Sciama.  Solo dicendo, on that.

Quote from: 93143
They're the same thing.  They both gravitate and have inertia.  The scale is wildly different, but that's immaterial.
http://en.wikipedia.org/wiki/Nordtvedt_effect

http://en.wikipedia.org/wiki/Equivalence_principle

Also note that the Nordtvedt effect has not been observed, despite multiple attempts.

I still object to 93143's take because the scale is so "wildly different".  The energy in a covalent bond is far smaller than the rest mass energy in the atom's nucleus.  On one level, a rubber band powerd balsawood airplane is the same thing as a C-5 Galaxy, but it would be unwise for our military to confuse the difference in scale.

But I also think Mulletron is premature to rest his argument on the one cite; note that the oracle has very little info on the .  It is by no means settled science.

Quote from: Mulletron
They are not the same thing in our universe...

Rest mass energy and covalent bond energy are not the same thing.

[Pre-posting edit:

I just noticed that Mulletron has addressed 93143's comment here: 

http://forum.nasaspaceflight.com/index.php?topic=29276.msg1267489#msg1267489 ]


Quote from: Mulletron
Remember that mass is constrained over space and energy is constrained over time!

Quote from: 93143
Perhaps you should rephrase this, because right now it makes no sense.

Well my take on that is that mass is energy bound in the tiny geometrical confines of a particle on the one hand. OTOH, energy, loosely speaqking, blobs out over space at a rate; and a rate is an acknowledgement of time.

I want to be careful not to get too "tit-for-tat' here, but one more comment:

I'm also assuming it is safe to say that Gravitational Mass can never be separated from Rest Mass, that they are invariant. I think it is safe to say that indeed gravitational self energy does indeed contribute to inertial mass, and that may not be the only thing or the only way which in which mechanisms contributes to inertial mass, in our universe, either way gravitational self energy DOES. Verified by experiment.

Quote from: 93143
What exactly do you mean by "verified by experiment"?

He means this.  Right now, gravitational and inertial mass appear to be the same thing, but he allows that may not be true, because there might be other mechanisms discovered which would have to be verified by experiment.

Quote from: 93143
And what do you mean by "safe"?

"Safe" in the sense that, should you provide calcs assuming gravitational and inertial mass to be the same value, your calcs would not be falsifiable, to date, on that basis.

Sometimes I just flat out don't get it.

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #1661 on: 10/07/2014 02:47 pm »
The MCL amplifier used is a Class AB amp.   The output, unless it has a DC blocking cap inside the amp, will have a DC offset = Vdd/2.   My guess is the amp does not have a DC blocking cap because that would affect the bandwidth and MCL likes to advertise their amplifiers as being broadband.

In an earlier setup, they used a Carvin DCM-1000 amp.  Is this pertinent to your argument?  See the attached PPT, p20.

the theory of this device has something to do with its cone shape.   But as an RF device it is a cavity filter.   It is also a Faraday cage because the inside is all Cu.

Nobody here has seen the inside of this device.  It may be full of compressed hummingbird wings, for all we know.  Or a vial of ebola.  Solo dicendo.

[Sorry.  The Inappropriate Humor Department (IHD) sneaks those in from time to time.]

Seriously, what's inside the cupric conical device?
Sometimes I just flat out don't get it.

Offline Rodal

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Re: EM Drive Developments
« Reply #1662 on: 10/07/2014 02:50 pm »
...White and his misunderstanding of vacuum fluctuations require nothing inside these resonators.  So why are they putting the [dielectric] stuff in?...
Very good question.  Since Dr. White or his staff are not involved in this thread, let me try an answer for him: they would probably state that the dielectric resonator functions as a resonator for millimeter-wavelength radio waves.   At the resonant frequencies, the microwaves form standing waves in the resonator, oscillating with large amplitudes. The resonant frequency is determined by the overall physical dimensions of the resonator and the dielectric constant of the material.

So, he would state that the dielectric resonator functions similarly to the cavity resonator, except that the radio waves are reflected by the large change in permittivity rather than by the conductivity of metal. At millimeter wave frequencies, metal surfaces become lossy reflectors, so dielectric resonators are used at these [shorter wavelength] frequencies.  So, effectively Dr.White would state that the dielectric resonator replaces the cavity at these smaller wavelengths.  The cavity's purpose is for resonance at the longer wavelengths, and the dielectric resonator is resonance at the millimeter wavelengths.  Since he is using both a cavity and the dielectric resonator, he must have been unsure as to which wavelength was the important one to resonate.  Similarly in the detection for axions in the ADMX experiment it was not clear at what wavelength they will find axions.  They started the ADMX experiment at longer wavelengths and now they are exploring shorter wavelengths.
« Last Edit: 10/07/2014 03:01 pm by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1663 on: 10/07/2014 02:53 pm »
The Woodward effect is trying to connect electromechanical self energy with inertial mass and gravitational self energy.
No offense, but you really should not write these fantastically long posts devoted to critiquing a theory you haven't read.  You have no way to know whether what you're criticizing is actual theory.  I can tell you, all of your comments about conservation are completely wrong, and you would know this if you had read the book.  You should not be arguing that Woodward is supposedly trying to do this or that, when you have not read his work.


I find it is best to try and break people's theories and find better ones. Then try to break those too. Not to fall in love with an idea that might not work, and hinder progress.
Okay.  Heh!  But do read the book.  It's a fun read!
« Last Edit: 10/07/2014 02:54 pm by Ron Stahl »

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #1664 on: 10/07/2014 02:59 pm »
So lets define clear terms and differences between them:

...
Do gluons need an environment in order to have mass? kinda but no, no because of precise language (Bill Clinton method)
...


Which is an excellent mixture of physics and politics.  Plus:  Even Socrates could understand your line of questioning!

Whoah, there kemosabe:  What?

Quote from: Mulletron
Do objects undergoing NO acceleration have inertial mass? NO

This one's not going to be easy to prove.  If I assume that the universe revolves (or pulsates, or expands, or whatever) around me, then I have no inertia. Fine, but that's probably not the case.

Show me ANY object or particle NOT undergoing some kind of acceleration.

Quote from:
ulletron
So we have to create a whole new universe within our real universe with slightly modified rules so we can get some work done by modifying inertia. This is what the shape of the emdrive does. It doesn't shield gravity and make the gravitational effects of inertia and more of less strong within the cavity. It gives the small percentage left, the .0000???? left a boost. So when we fire photons through the thing from small to large end, they gain inertial mass across the length of the cavity. Normally this would be equaled out and canceled in our universe because spacetime is symmetrical. But in the tubes universe, spacetime is not symmetrical. There is a bias.

My bold.  That's what they say, sure.  It's an extraordinary claim to think that a "new" universe" can be created, with its own laws, for such a small expenditure of energy and mass.

Totally great post.
Sometimes I just flat out don't get it.

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1665 on: 10/07/2014 02:59 pm »
...White and his misunderstanding of vacuum fluctuations require nothing inside these resonators.  So why are they putting the [dielectric] stuff in?...
Very good question.  Since Dr. White or his staff are not involved in this thread, let me try an answer for him: they would probably state that the dielectric resonator functions as a resonator for millimeter-wavelength radio waves.   At the resonant frequencies, the microwaves form standing waves in the resonator, oscillating with large amplitudes. The resonant frequency is determined by the overall physical dimensions of the resonator and the dielectric constant of the material.

So, he would state that the dielectric resonator functions similarly to the cavity resonator, except that the radio waves are reflected by the large change in permittivity rather than by the conductivity of metal. At millimeter wave frequencies, metal surfaces become lossy reflectors, so dielectric resonators are used at these [shorter wavelength] frequencies.  So, effectively Dr.White would state that the dielectric resonator replaces the cavity at these smaller wavelengths.  The cavity's purpose is for resonance at the longer wavelengths, and the dielectric resonator is resonance at the millimeter wavelengths.
I'm lost.  They're powering with <2Ghz.  How are they getting millimeter waves (30-300Ghz) and if that's what they wanted, why would they not just use a millimeter wave amp?  I've sent Paul links to dozens of them over the years.

To I would note that very few materials have ionic responses in the millimeter wave range.  So there wouldn't be much if any bulk acceleration at these frequencies.

Offline Rodal

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Re: EM Drive Developments
« Reply #1666 on: 10/07/2014 03:14 pm »
...White and his misunderstanding of vacuum fluctuations require nothing inside these resonators.  So why are they putting the [dielectric] stuff in?...
Very good question.  Since Dr. White or his staff are not involved in this thread, let me try an answer for him: they would probably state that the dielectric resonator functions as a resonator for millimeter-wavelength radio waves.   At the resonant frequencies, the microwaves form standing waves in the resonator, oscillating with large amplitudes. The resonant frequency is determined by the overall physical dimensions of the resonator and the dielectric constant of the material.

So, he would state that the dielectric resonator functions similarly to the cavity resonator, except that the radio waves are reflected by the large change in permittivity rather than by the conductivity of metal. At millimeter wave frequencies, metal surfaces become lossy reflectors, so dielectric resonators are used at these [shorter wavelength] frequencies.  So, effectively Dr.White would state that the dielectric resonator replaces the cavity at these smaller wavelengths.  The cavity's purpose is for resonance at the longer wavelengths, and the dielectric resonator is resonance at the millimeter wavelengths.
I'm lost.  They're powering with <2Ghz.  How are they getting millimeter waves (30-300Ghz) and if that's what they wanted, why would they not just use a millimeter wave amp?  I've sent Paul links to dozens of them over the years.

To I would note that very few materials have ionic responses in the millimeter wave range.  So there wouldn't be much if any bulk acceleration at these frequencies.
Well they wrote a lengthy report with lots of pictures of a vacuum chamber, description of a vacuum chamber and in the end they did not conduct the experiments in the vacuum chamber [and their explanation is because of the electrolytic capacitors?].  Maybe eventually they were planning to go over 30 GHz using a different amplifier ?

They tried removing the dielectric resonator from the truncated cone and they measured no thrust without the dielectric resonator. They offer no theoretical explanation for why the dielectric resonator plays such an important role in their results at ~2 GHz

They do not state what dielectric resonator material they used for the truncated cone experiments.
« Last Edit: 10/07/2014 03:19 pm by Rodal »

Offline Notsosureofit

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Re: EM Drive Developments
« Reply #1667 on: 10/07/2014 03:29 pm »
...White and his misunderstanding of vacuum fluctuations require nothing inside these resonators.  So why are they putting the [dielectric] stuff in?...
Very good question.  Since Dr. White or his staff are not involved in this thread, let me try an answer for him: they would probably state that the dielectric resonator functions as a resonator for millimeter-wavelength radio waves.   At the resonant frequencies, the microwaves form standing waves in the resonator, oscillating with large amplitudes. The resonant frequency is determined by the overall physical dimensions of the resonator and the dielectric constant of the material.

So, he would state that the dielectric resonator functions similarly to the cavity resonator, except that the radio waves are reflected by the large change in permittivity rather than by the conductivity of metal. At millimeter wave frequencies, metal surfaces become lossy reflectors, so dielectric resonators are used at these [shorter wavelength] frequencies.  So, effectively Dr.White would state that the dielectric resonator replaces the cavity at these smaller wavelengths.  The cavity's purpose is for resonance at the longer wavelengths, and the dielectric resonator is resonance at the millimeter wavelengths.  Since he is using both a cavity and the dielectric resonator, he must have been unsure as to which wavelength was the important one to resonate.  Similarly in the detection for axions in the ADMX experiment it was not clear at what wavelength they will find axions.  They started the ADMX experiment at longer wavelengths and now they are exploring shorter wavelengths.

Are you thinking 30GHz ?

Yup, I guess you are !
« Last Edit: 10/07/2014 03:33 pm by Notsosureofit »

Offline Rodal

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Re: EM Drive Developments
« Reply #1668 on: 10/07/2014 03:36 pm »
...White and his misunderstanding of vacuum fluctuations require nothing inside these resonators.  So why are they putting the [dielectric] stuff in?...
Very good question.  Since Dr. White or his staff are not involved in this thread, let me try an answer for him: they would probably state that the dielectric resonator functions as a resonator for millimeter-wavelength radio waves.   At the resonant frequencies, the microwaves form standing waves in the resonator, oscillating with large amplitudes. The resonant frequency is determined by the overall physical dimensions of the resonator and the dielectric constant of the material.

So, he would state that the dielectric resonator functions similarly to the cavity resonator, except that the radio waves are reflected by the large change in permittivity rather than by the conductivity of metal. At millimeter wave frequencies, metal surfaces become lossy reflectors, so dielectric resonators are used at these [shorter wavelength] frequencies.  So, effectively Dr.White would state that the dielectric resonator replaces the cavity at these smaller wavelengths.  The cavity's purpose is for resonance at the longer wavelengths, and the dielectric resonator is resonance at the millimeter wavelengths.  Since he is using both a cavity and the dielectric resonator, he must have been unsure as to which wavelength was the important one to resonate.  Similarly in the detection for axions in the ADMX experiment it was not clear at what wavelength they will find axions.  They started the ADMX experiment at longer wavelengths and now they are exploring shorter wavelengths.

Are you thinking 30GHz ?
Yes, not clear what was in their mind.  Just like they wrote a lengthy report with lots of pictures of a vacuum chamber, description of a vacuum chamber and in the end they did not conduct the experiments in the vacuum chamber [and their explanation is because of the electrolytic capacitors?].

If the purpose was just to test at room pressure operating conditions they would have been much better off using an oil-damped Cavendish type of balance, yet they started a program with a magnetically damped inverted pendulum that could fit inside their small vacuum chamber. But in the end they did not use their vacuum chamber.

 Maybe eventually they were planning to go over 30 GHz using a different amplifier ?

They tried removing the dielectric resonator and perhaps they were surprised (?) to find out they measured no thrust whatsoever. They offer no theoretical explanation for this. It is though, an experimental fact we have to understand and explain: the paramount role of the dielectric resonator at ~2 GHz
« Last Edit: 10/07/2014 03:40 pm by Rodal »

Offline Mulletron

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Re: EM Drive Developments
« Reply #1669 on: 10/07/2014 03:56 pm »
Quoting myself here: "Remember that mass is constrained over space and energy is constrained over time!"

This isn't any new insight I have. Nothing I throw around are my own insight, except the mistakes I make.

Here's what I mean though:

Mass over symmetric space, energy over asymmetric time. Matter is just energy constrained over time that has a high probability of being there occupying a point in space. Particles in the vacuum have a low probability of being there, because they pop in and out of existence so quickly. Because of that, forces associated with mass such as momentum, acceleration, have to be conserved. Momentum, inertia, acceleration are also constrained in space. This also gives us an arrow of time to follow over spacetime.  The closer you get to C, this breaks down.

I can go up, down, left or right. I push something up, I get pushed right back down. I can only go forward in time. Anything that has a symmetry also has and associated conservation. Until the symmetry is broken.
« Last Edit: 10/07/2014 03:57 pm by Mulletron »
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Offline aero

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Re: EM Drive Developments
« Reply #1670 on: 10/07/2014 03:56 pm »
Question - Is there any way to know the shapes of the standing waves within the cavity, with and without the resonator?
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Offline Rodal

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Re: EM Drive Developments
« Reply #1671 on: 10/07/2014 04:00 pm »
Question - Is there any way to know the shapes of the standing waves within the cavity, with and without the resonator?
See here for a curved truncated cone:  http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html
for the cavity itself (not the dielectric resonator)


Observe that the ends, however are not flat in this solution for 1/r not equal to zero.  Shawyer's and NASA truncated cone have flat ends with 1/r = 0 (r-> Infinity at ends)
« Last Edit: 10/07/2014 04:07 pm by Rodal »

Offline Notsosureofit

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Re: EM Drive Developments
« Reply #1672 on: 10/07/2014 04:02 pm »
...White and his misunderstanding of vacuum fluctuations require nothing inside these resonators.  So why are they putting the [dielectric] stuff in?...
Very good question.  Since Dr. White or his staff are not involved in this thread, let me try an answer for him: they would probably state that the dielectric resonator functions as a resonator for millimeter-wavelength radio waves.   At the resonant frequencies, the microwaves form standing waves in the resonator, oscillating with large amplitudes. The resonant frequency is determined by the overall physical dimensions of the resonator and the dielectric constant of the material.

So, he would state that the dielectric resonator functions similarly to the cavity resonator, except that the radio waves are reflected by the large change in permittivity rather than by the conductivity of metal. At millimeter wave frequencies, metal surfaces become lossy reflectors, so dielectric resonators are used at these [shorter wavelength] frequencies.  So, effectively Dr.White would state that the dielectric resonator replaces the cavity at these smaller wavelengths.  The cavity's purpose is for resonance at the longer wavelengths, and the dielectric resonator is resonance at the millimeter wavelengths.  Since he is using both a cavity and the dielectric resonator, he must have been unsure as to which wavelength was the important one to resonate.  Similarly in the detection for axions in the ADMX experiment it was not clear at what wavelength they will find axions.  They started the ADMX experiment at longer wavelengths and now they are exploring shorter wavelengths.

Are you thinking 30GHz ?
Yes, not clear what was in their mind.  Just like they wrote a lengthy report with lots of pictures of a vacuum chamber, description of a vacuum chamber and in the end they did not conduct the experiments in the vacuum chamber [and their explanation is because of the electrolytic capacitors?].

If the purpose was just to test at room pressure operating conditions they would have been much better off using an oil-damped Cavendish type of balance, yet they started a program with a magnetically damped inverted pendulum that could fit inside their small vacuum chamber. But in the end they did not use their vacuum chamber.

 Maybe eventually they were planning to go over 30 GHz using a different amplifier ?

They tried removing the dielectric resonator and perhaps they were surprised (?) to find out they measured no thrust whatsoever. They offer no theoretical explanation for this. It is though, an experimental fact we have to understand and explain: the paramount role of the dielectric resonator at ~2 GHz

Dielectrics can  have very interesting (weird) responses vs frequency which are caused by individual dipole elements passing through resonance.  These are all material related, but in general, the dielectric constants decrease w/ frequency except at these resonance points.  Artificial resonators are used to construct metamaterials of engineered characteristics.

Oh, and they aren't necessarily linear.

Offline Rodal

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Re: EM Drive Developments
« Reply #1673 on: 10/07/2014 04:05 pm »
...White and his misunderstanding of vacuum fluctuations require nothing inside these resonators.  So why are they putting the [dielectric] stuff in?...
Very good question.  Since Dr. White or his staff are not involved in this thread, let me try an answer for him: they would probably state that the dielectric resonator functions as a resonator for millimeter-wavelength radio waves.   At the resonant frequencies, the microwaves form standing waves in the resonator, oscillating with large amplitudes. The resonant frequency is determined by the overall physical dimensions of the resonator and the dielectric constant of the material.

So, he would state that the dielectric resonator functions similarly to the cavity resonator, except that the radio waves are reflected by the large change in permittivity rather than by the conductivity of metal. At millimeter wave frequencies, metal surfaces become lossy reflectors, so dielectric resonators are used at these [shorter wavelength] frequencies.  So, effectively Dr.White would state that the dielectric resonator replaces the cavity at these smaller wavelengths.  The cavity's purpose is for resonance at the longer wavelengths, and the dielectric resonator is resonance at the millimeter wavelengths.  Since he is using both a cavity and the dielectric resonator, he must have been unsure as to which wavelength was the important one to resonate.  Similarly in the detection for axions in the ADMX experiment it was not clear at what wavelength they will find axions.  They started the ADMX experiment at longer wavelengths and now they are exploring shorter wavelengths.

Are you thinking 30GHz ?
Yes, not clear what was in their mind.  Just like they wrote a lengthy report with lots of pictures of a vacuum chamber, description of a vacuum chamber and in the end they did not conduct the experiments in the vacuum chamber [and their explanation is because of the electrolytic capacitors?].

If the purpose was just to test at room pressure operating conditions they would have been much better off using an oil-damped Cavendish type of balance, yet they started a program with a magnetically damped inverted pendulum that could fit inside their small vacuum chamber. But in the end they did not use their vacuum chamber.

 Maybe eventually they were planning to go over 30 GHz using a different amplifier ?

They tried removing the dielectric resonator and perhaps they were surprised (?) to find out they measured no thrust whatsoever. They offer no theoretical explanation for this. It is though, an experimental fact we have to understand and explain: the paramount role of the dielectric resonator at ~2 GHz

Dielectrics can  have very interesting (weird) responses vs frequency which are caused by individual dipole elements passing through resonance.  These are all material related, but in general, the dielectric constants decrease w/ frequency except at these resonance points.  Artificial resonators are used to construct metamaterials of engineered characteristics.

Oh, and they aren't necessarily linear.
Yes, thank you.  That must be the explanation.  Unfortunately they did not specify the material that was used as a dielectric resonator for the truncated cone.  Perhaps we could consider the high likelihood of it being a ceramic, as proposed by @zen-in

Offline Rodal

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Re: EM Drive Developments
« Reply #1674 on: 10/07/2014 04:27 pm »
..
Dielectrics can  have very interesting (weird) responses vs frequency which are caused by individual dipole elements passing through resonance.  These are all material related, but in general, the dielectric constants decrease w/ frequency except at these resonance points.  Artificial resonators are used to construct metamaterials of engineered characteristics.

Oh, and they aren't necessarily linear.
And the experiments (see attached) show a very nonlinear response (a 6 fold increase in power input results in a decrease of thrust force of 10%, and an increase in frequency of 0.3% (practically the same frequency) results in 2.5 times higher Q and 1/2 the thrust force).

The copper does not have a nonlinear response.  The empty cavity does not have a nonlinear response.

What can be responsible for a nonlinear response?

The dielectric material of course
« Last Edit: 10/07/2014 04:29 pm by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1675 on: 10/07/2014 04:29 pm »
I think that's unlikely.  Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin.  Paul believes both Woodward and White are correct.  Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory.  Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time.  Teflon has a very poor k~2, but it is good up into microwave territory.  Most ceramics the k drops off way before.  In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal.  They are certainly not using that.

Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.

Offline Rodal

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Re: EM Drive Developments
« Reply #1676 on: 10/07/2014 04:34 pm »
I think that's unlikely.  Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin.  Paul believes both Woodward and White are correct.  Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory.  Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time.  Teflon has a very poor k~2, but it is good up into microwave territory.  Most ceramics the k drops off way before.  In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal.  They are certainly not using that.

Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.

Thanks, Ron as your post should motivate further reflection on what dielectric material NASA used for the truncated cone. Teflon was an initial assumption (just based on the fact that Teflon was the only dielectric material mentioned in the report, albeit for the Cannae drive).  We didn't have your additional arguments.

Let me add another argument: nonlinear response from Teflon (PTFE), particularly with Teflon exposed to an electric field ~ 45000 Volt/meter [Note this is based on back of the envelope calculations: not too different a field than from the maximum for the Cannae drive, NASA did not give the COMSOL numbers for the truncated cone electric field, particularly at the dielectric resonator]

Interested on what others  think about Ron's reasoning above for Teflon instead of a ceramic as the dielectric  for NASA's truncated cone.
« Last Edit: 10/07/2014 05:12 pm by Rodal »

Offline aero

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Re: EM Drive Developments
« Reply #1677 on: 10/07/2014 05:02 pm »
Question - Is there any way to know the shapes of the standing waves within the cavity, with and without the resonator?
See here for a curved truncated cone:  http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html
for the cavity itself (not the dielectric resonator)


Observe that the ends, however are not flat in this solution for 1/r not equal to zero.  Shawyer's and NASA truncated cone have flat ends with 1/r = 0 (r-> Infinity at ends)
Thanks. That's helpful, I think.

Edit - fixed the end quote.
« Last Edit: 10/07/2014 05:06 pm by aero »
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Offline Notsosureofit

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Re: EM Drive Developments
« Reply #1678 on: 10/07/2014 05:11 pm »
I think that's unlikely.  Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin.  Paul believes both Woodward and White are correct.  Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory.  Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time.  Teflon has a very poor k~2, but it is good up into microwave territory.  Most ceramics the k drops off way before.  In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal.  They are certainly not using that.

Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.

Thanks, Ron as your post should motivate further reflection on what dielectric material NASA used for the truncated cone. Teflon was an initial assumption (just based on the fact that Teflon was the only dielectric material mentioned in the report, albeit for the Cannae drive).  We didn't have your additional arguments.

Let me add another argument: I expect a more nonlinear response from Teflon (PTFE) than from a ceramic, particularly with Teflon exposed to an electric field ~ 45000 Volt/meter [Note this is based on back of the envelope calculations: not too different a field than from the maximum for the Cannae drive, NASA did not give the COMSOL numbers for the truncated cone electric field, particularly at the dielectric resonator]

Interested on what others  think about Ron's reasoning above for Teflon instead of a ceramic as the dielectric  for NASA's truncated cone.

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19700003017.pdf

???

The results of this investigation along with existing data at lower frequencies were used to verify the theoretically predicted transition which occurs in the microwave region and continues into the millimeter region.

see p 33 and esp p45 !!!
« Last Edit: 10/07/2014 05:21 pm by Notsosureofit »

Offline Rodal

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Re: EM Drive Developments
« Reply #1679 on: 10/07/2014 05:17 pm »
I think that's unlikely.  Paul has been looking at teflon for along time and probably because he is of the opinion that Woodward's and White's models form different sides of the same coin.  Paul believes both Woodward and White are correct.  Even though i can't agree, I would note that one logical response to this belief is to stick dielectric into a resonator to test Jim's theory.  Sonny would never do this--test Woodward's work--unless he had convinced himself he was testing his own model at the same time.  Teflon has a very poor k~2, but it is good up into microwave territory.  Most ceramics the k drops off way before.  In fact I only know of one that maintains it's high k to about 1 Ghz, and that is single crystal.  They are certainly not using that.

Probably just a teflon sheet, though if its there to check Woodward's theory, then it is installed with one side against one of the ends of the resonator chamber and would act in 1/4 wave fashion.

Thanks, Ron as your post should motivate further reflection on what dielectric material NASA used for the truncated cone. Teflon was an initial assumption (just based on the fact that Teflon was the only dielectric material mentioned in the report, albeit for the Cannae drive).  We didn't have your additional arguments.

Let me add another argument: I expect a more nonlinear response from Teflon (PTFE) than from a ceramic, particularly with Teflon exposed to an electric field ~ 45000 Volt/meter [Note this is based on back of the envelope calculations: not too different a field than from the maximum for the Cannae drive, NASA did not give the COMSOL numbers for the truncated cone electric field, particularly at the dielectric resonator]

Interested on what others  think about Ron's reasoning above for Teflon instead of a ceramic as the dielectric  for NASA's truncated cone.

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19700003017.pdf

???

Great reference.  See page 45 for Teflon.  At 2Ghz it starts to get nonlinear, however this is at what amount of electric field and temperature?

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