Author Topic: EM Drive Developments Thread 1  (Read 1472522 times)

Offline Mulletron

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Re: EM Drive Developments
« Reply #1800 on: 10/09/2014 02:41 pm »
Nobody is arguing with you over the walls of the cavity being part of the rindler horizon. The unruh waves fit between the walls of the cavity and the approaching rindler horizon.
« Last Edit: 10/09/2014 02:42 pm by Mulletron »
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Offline Rodal

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Re: EM Drive Developments
« Reply #1801 on: 10/09/2014 02:42 pm »
His ideas sold me the steak but not the whole cow.
OK, but he clearly states that his assumption is that the copper walls are acting as an event horizon, and he gives his reason why:

<<the Unruh waves are affected by the copper wall because they are partly em waves and the electrons in the copper move to cancel the field, so the Unruh wave patterns have to close at the wall just as at the Hubble horizon (but for a different reason)>>
« Last Edit: 10/09/2014 02:45 pm by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1802 on: 10/09/2014 02:42 pm »
http://m.phys.org/news/2011-07-gyroscope-unexplained-due-inertia.html

Not comparable.

The ring and the gyro are 2 physical systems, separate, but in common with the universe.

Emdrive is 2 separate physical systems one inside the other. In series.


Also there is no supercooled rotating anything in emdrive.

From the link:  "causing the gyroscope’s inertial mass to decrease to less than its gravitational mass."
Just noting, all of GR stands on EEP and EEP says that inertial and gravitational mass are always the same.  There are weak and strong readings of this, but what Dr. McCulloch is proposing would seem to imply all of GR is wrong, as EEP is wrong.  Or am I overstating the case?

I do however appreciate when anyone tries to make sense of Tajmar's findings.  It was a big surprise that he got the same readings both with and without the superconducting ring that was supposed to be causing this effect.
« Last Edit: 10/09/2014 02:43 pm by Ron Stahl »

Offline Mulletron

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Re: EM Drive Developments
« Reply #1803 on: 10/09/2014 02:49 pm »
http://m.phys.org/news/2011-07-gyroscope-unexplained-due-inertia.html

Not comparable.

The ring and the gyro are 2 physical systems, separate, but in common with the universe.

Emdrive is 2 separate physical systems one inside the other. In series.


Also there is no supercooled rotating anything in emdrive.

From the link:  "causing the gyroscope’s inertial mass to decrease to less than its gravitational mass."
Just noting, all of GR stands on EEP and EEP says that inertial and gravitational mass are always the same.  There are weak and strong readings of this, but what Dr. McCulloch is proposing would seem to imply all of GR is wrong, as EEP is wrong.  Or am I overstating the case?

I do however appreciate when anyone tries to make sense of Tajmar's findings.  It was a big surprise that he got the same readings both with and without the superconducting ring that was supposed to be causing this effect.

He is proposing that EEP is wrong. So am I. EEP falls apart under very very low accelerations.

EEP is an illusion because it is true MOST of the time.

EEP is right most of the time.

Mach's ideas were informed by the notion of, if you can't observe it, it is insignificant. That was a very big mistake and that is why everyone believes inertial mass is the same as gravitational mass ALL OF THE TIME.

It clearly is not.

Also, somehow, Mach's generalizations about the origins of inertial mass, which informed Einstein only in principle by loose association with Mach's ideas, became a strong equivalence that should not be there.

A generalization, which dismisses what which you can't observe cannot inform a strong equivalence.

Tests of the equivalence principle pass every single time here and now. Not at the edges of our galaxy and beyond.

His test of the Tajmar effect is analogous to the Nordtvedt effect. (difference is angular vs linear)

Nobody is arguing with you over the walls of the cavity being part of the rindler horizon. The unruh waves fit between the walls of the cavity and the approaching rindler horizon.


The rindler sphere is defined by the boundaries of the cavity *(horizon 1) and the approaching Rindler horizon (horizon 2).
« Last Edit: 10/09/2014 03:01 pm by Mulletron »
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Offline Mulletron

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Re: EM Drive Developments
« Reply #1804 on: 10/09/2014 03:02 pm »
GR doesn't have to be wrong in order for EEP to not fit every situation. Especially artificial situations.

"The rindler sphere is defined by the boundaries of the cavity *(horizon 1) and the approaching Rindler horizon (horizon 2)."

This new rindler sphere I just described denotes a new rindler sphere. A whole new variable.

There are 2 rindler spheres, well ellipses is more accurate. Squashed spheres then. They share an arc. The one as I drew and the one as I described. I need to add an arc to the drawing.

Thanks!

Edit:

Added pic with changes. Close enough.

It seems evident to me that MIHSC describes only the inertia component of emdrive which then enables Dr. White's ideas of thrust interactions.

Prove me wrong.
« Last Edit: 11/02/2014 06:50 am by Mulletron »
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Offline frobnicat

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Re: EM Drive Developments
« Reply #1805 on: 10/09/2014 03:56 pm »

I guess its time for my 10^7 contribution.

I've attached a current estimate of dark matter in the solar system, and for convenience converted 16.5E16 kg / AU^3 to 4.5E-17 kg/m^3.  That is quite a lot more than your number...

Yeah, I just, you know, forgot the G in GeV. Off by 9 orders of magnitude. Post corrected. Many thanks for not making myself a fool for too long. ...

This is weakly interacting after all. Please detect DM before pushing too much on it.

I was wondering about all the strike thrus.  Just go ahead and edit it so it reads better.  Add a "mea culpa" at the end.  I'm not gonna ask for an apoligy, 'cause I drop zeros all the time.

It's true tho, that you can't push very hard on something that is so rare.  But then I got confused.  You're not talking about "DM fusion", right?

Ai chihuahua.

http://samos.martech.fsu.edu/chapters/chapters/md.PDF
http://cua.mit.edu/8.422_S07/BECinDiluteGases205-214.pdf

If you grok those equations that I wouldn't touch with a ten foot pole then kudos, can't say more.
Then maybe you can say what 'a' and 'k' stand for in this apparently relevant paper :
Quote
Thus, again we can identify cs = k/(2ma) as an effective sound speed of the axion fluid.

My poor man citation will be from anonymous contributors on reddit forum (this is less classy than proper publications...) :
Quote from: TheAlgebrator
The speed of sound largely depends on the absolute temperature of the gas, and not so much due to the enhancement of quantum mechanical effects.
...
The question wasn't asking why it was 0.0022 m/s but why sound moves so slowly (compared to air). We are comparing a low, almost zero, energy medium to normal air. The elephant in the room is temperature. Air is around 300 Kelvin and a BEC has temperatures in the nano kelvin range. As mentioned in [1] paragraph 3, a good estimate for the speed of sound in an ideal gas as a function of temperature is speed=constant*sqrt(Absolute Temperature). Calculating the speed of sound in a BEC using this model I got an answer of the same magnitude as [2].

also

Quote
As far as explosions go, the atoms comprising a BEC are still very cold and even after a shockwave you would expect a relatively slow thermal expansion of the atoms. The way the atoms expansion would be similar to glass shattering into tiny pieces and expanding radially outward, but only very slowly.

I can imagine pushing too hard on DM and breaking the fragile aether into dark shards, in slow motion.

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1806 on: 10/09/2014 04:04 pm »
GR doesn't have to be wrong in order for EEP to not fit every situation. Especially artificial situations. . .

. . .Prove me wrong.
I don't need to prove you wrong.  What you're saying is completely at odds with GR and history, as well as simple observations one can make on wiki. You are simply wrong.  All of GR depends upon weak equivalence, and in addition, Einstein's version or EEP, that holds equivalence is velocity and acceleration independent. All of GR requires that inertia and gravitational mass be the same under all conditions, or a preferred frame of reference will emerge.

I'm sorry but you're just wrong.  Look it up on Wiki.

Offline Mulletron

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Re: EM Drive Developments
« Reply #1807 on: 10/09/2014 04:17 pm »
GR doesn't have to be wrong in order for EEP to not fit every situation. Especially artificial situations. . .

. . .Prove me wrong.
I don't need to prove you wrong.  What you're saying is completely at odds with GR and history, as well as simple observations one can make on wiki. You are simply wrong.  All of GR depends upon weak equivalence, and in addition, Einstein's version or EEP, that holds equivalence is velocity and acceleration independent. All of GR requires that inertia and gravitational mass be the same under all conditions, or a preferred frame of reference will emerge.

I'm sorry but you're just wrong.  Look it up on Wiki.

Seriously, stop using wikipedia to make conclusions. My version of history is consistent. Read about Ernst Mach.

I'm going to use Wikipedia itself to shutdown your argument on my views of Machian Philosophy of science:

Mach is attributed with a number of principles that distill his ideal of physical theorisation — what is now called "Machian physics":

    1. It should be based entirely on directly observable phenomena (in line with his positivistic leanings)[12]
    2. It should completely eschew absolute space and time in favor of relative motion[13]
    3. Any phenomena that would seem attributable to absolute space and time (e.g. inertia, and centrifugal force) should instead be seen as emerging from the large scale distribution of matter in the universe.

IRT #1, Were the accelerations of objects in interstellar space "observable" to anyone in Mach's time?

The commonly held ideas of the unshakable equivalence of gravitational and inertial mass are based on a slippery slope of excluding directly observable phenomena.

Also Mach didn't accept Einstein. He didn't even accept the atom.

In the end Mach was MOSTLY right, but imprecise. That still holds us back today. Now we have to believe in dark matter and are out looking for that instead of questioning our own reasoning on the origins of inertial mass.

One of these days we'll wake up.

« Last Edit: 10/09/2014 04:22 pm by Mulletron »
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Offline Rodal

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Re: EM Drive Developments
« Reply #1808 on: 10/09/2014 04:23 pm »
The important thing is what predictions are made by McCulloch's MiHsC deviation from EEP that differ from GR in such a way that the deviation can be checked agaisnt astrophysical data to nullify one or the other.  Have all the consequences from this deviation from EEP been mathematically explored  and checked against measurements?

Offline Mulletron

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Re: EM Drive Developments
« Reply #1809 on: 10/09/2014 04:29 pm »
WE are developing emdrive by asking these hard questions. You can't explain anomalous thrust using archaic reasoning. Now let's find that data! Or put mihsc to bed.
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Offline Rodal

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Re: EM Drive Developments
« Reply #1810 on: 10/09/2014 04:33 pm »
Of course, McCulloch's theory needs to satisfy, for example, these tests within the tests's precision:


Researcher   Year   Method   Result
Friedrich Wilhelm Bessel   1832   measure the period of pendulums of different mass but identical length   no measurable difference
Loránd Eötvös   1908   measure the torsion on a wire, suspending a balance beam, between two nearly identical masses under the acceleration of gravity and the rotation of the Earth   difference is less than 1 part in 109
Roll, Krotkov and Dicke   1964   Torsion balance experiment, dropping aluminum and gold test masses   |\eta(\mathrm{Al},\mathrm{Au})|=(1.3\pm1.0)\times10^{-11}[8]
David Scott   1971   Dropped a falcon feather and a hammer at the same time on the Moon   no detectable difference (not a rigorous experiment, but very dramatic being the first lunar one[9])
Braginsky and Panov   1971   Torsion balance, aluminum and platinum test masses, measuring acceleration towards the sun   difference is less than 1 part in 10^12
Eöt-Wash group   1987–   Torsion balance, measuring acceleration of different masses towards the earth, sun and galactic center, using several different kinds of masses   \eta(\text{Earth},\text{Be-Ti})=(0.3 \pm 1.8   )        \times 10^{-13}[10]
« Last Edit: 10/09/2014 04:36 pm by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1811 on: 10/09/2014 04:38 pm »
No one who believes Mach's Principle believes it based upon some authority, so chasing down Mach's other beliefs is just a distraction fallacy.  The point we're here concerned with is not even Mach.  It is Einstein.  So don't change the subject.  If you believe that inertial and gravitational mass are at any time different, then you believe a preferred reference frame will emerge and all of GR is completely WRONG.  This is why everyone who understands Einstein's theories holds that both the weak equivalence and Einstein's equivalence principle MUST be true.

Sorry, you you need to know this theory is contradictory to good ol' Uncle Al.  It is therefore suspect and for most of us, not to be taken seriously.  GR has a fantastical amount of observational support, and none of this has anything whatsoever to do with Mach refusing to believe in atoms.

Offline Mulletron

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Re: EM Drive Developments
« Reply #1812 on: 10/09/2014 04:45 pm »
@Ron
You realize that MET thrusters ALSO depend on mihsc being correct right? Also Mach informed Einstein. There is no distraction. Being obtuse doesn't give rise to progress either. Respectfully. Let's work together here.
« Last Edit: 10/09/2014 04:49 pm by Mulletron »
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Offline Mulletron

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Re: EM Drive Developments
« Reply #1813 on: 10/09/2014 04:52 pm »
Of course, McCulloch's theory needs to satisfy, for example, these tests within the tests's precision:


Researcher   Year   Method   Result
Friedrich Wilhelm Bessel   1832   measure the period of pendulums of different mass but identical length   no measurable difference
Loránd Eötvös   1908   measure the torsion on a wire, suspending a balance beam, between two nearly identical masses under the acceleration of gravity and the rotation of the Earth   difference is less than 1 part in 109
Roll, Krotkov and Dicke   1964   Torsion balance experiment, dropping aluminum and gold test masses   |\eta(\mathrm{Al},\mathrm{Au})|=(1.3\pm1.0)\times10^{-11}[8]
David Scott   1971   Dropped a falcon feather and a hammer at the same time on the Moon   no detectable difference (not a rigorous experiment, but very dramatic being the first lunar one[9])
Braginsky and Panov   1971   Torsion balance, aluminum and platinum test masses, measuring acceleration towards the sun   difference is less than 1 part in 10^12
Eöt-Wash group   1987–   Torsion balance, measuring acceleration of different masses towards the earth, sun and galactic center, using several different kinds of masses   \eta(\text{Earth},\text{Be-Ti})=(0.3 \pm 1.8   )        \times 10^{-13}[10]

Yeah but there is a distinction. Those above tests which are in fact correct in every way, are in a different domain. LOCAL They don't hold over interstellar domains. (dropping a hammer from the very edge of the galaxy, lasering a distant moon very very far away) Big difference. There is a horizon where the above tests fall apart, where Machian inertia no longer holds true as described.

MiHsC depends on the origin of inertia being Machian, but is derived differently.
There is a Machian limit out there.
« Last Edit: 10/09/2014 05:01 pm by Mulletron »
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Offline Rodal

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Re: EM Drive Developments
« Reply #1814 on: 10/09/2014 05:02 pm »
GR doesn't have to be wrong in order for EEP to not fit every situation. Especially artificial situations.

"The rindler sphere is defined by the boundaries of the cavity *(horizon 1) and the approaching Rindler horizon (horizon 2)."

This new rindler sphere I just described denotes a new rindler sphere. A whole new variable.

There are 2 rindler spheres, well ellipses is more accurate. Squashed spheres then. They share an arc. The one as I drew and the one as I described. I need to add an arc to the drawing.

Thanks!

Edit:

Added pic with changes. Close enough.

It seems evident to me that MIHSC describes only the inertia component of emdrive which then enables Dr. White's ideas of thrust interactions.

Prove me wrong.
First of all thank you for going through the effort to put your ideas into pictorial form.  That is very commendable, as it much easier for people to write words.

Second, it appears to me that you favor physical (rather than mathematical) explanations.  I draw that conclusion from the notes about Casimir attraction, and for you searching for a physical interaction that will ultimately enable the movement.   I operate differently, I prefer John von Neumann's mathematical approach to physics.  One critical aspect of this approach are conservation laws.  I don't interpret the Casimir effect as an attractive force due to the quantum vacuum.  What I see in Prof. McCulloch's formulation is the assumption that a finite number of Unruh waves can fit in one or the other surfaces perpendicular to the 1 D direction of motion.  Again to me conservation of momentum is a critical law and given a change of inertia, that there must be a force (producing an acceleration) to conserve momentum is a satisfactory explanation.  The reason why this looks "unphysical" is because we are all accustomed to EEP: anything that deviates from EEP by its very nature feels unphysical.  Explaining the movement as enabling Dr. White's interactions with the Quantum Vacuum (modeled by him as a plasma) may be helpful to you but not to me, I just prefer McCulloch's explanation that it must be acted by a force to conserve momentum.  And as difficult as it maybe if forced to dispense with one or the other, I rather dispense with EEP than with conservation of momentum.  Of course, one still has to consider that the NASA, Chinese and Shawyer experiments still maybe an experimental artifact and they may not serve as a means of propulsion in outer space.
« Last Edit: 10/09/2014 05:09 pm by Rodal »

Offline Notsosureofit

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Re: EM Drive Developments
« Reply #1815 on: 10/09/2014 05:06 pm »

If you grok those equations that I wouldn't touch with a ten foot pole then kudos, can't say more.
Then maybe you can say what 'a' and 'k' stand for in this apparently relevant paper :
Quote
Thus, again we can identify cs = k/(2ma) as an effective sound speed of the axion fluid.

Well, k is the wave number and a is a coefficient (where I would have just used 1/2 as in the simpleminded "perfect" superconducting cavity case)

Great ref by the by.  If I can grok it at all it says I should be able to write a 3 PD set of equations for the EM cavity and insert coefficients for a viscous term using the equation of state they give.  But, it still looks like the sound speed, etc., has to be experimentally determined from the axion mass.  (the 300m/s was the assumption to get a power figure as an example)

And NO, I'm not promising I CAN write those equations (and solve them with the boundary conditions), but I have been in that situation in the dim, very dark past.

Offline Mulletron

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Re: EM Drive Developments
« Reply #1816 on: 10/09/2014 05:32 pm »
GR doesn't have to be wrong in order for EEP to not fit every situation. Especially artificial situations.

"The rindler sphere is defined by the boundaries of the cavity *(horizon 1) and the approaching Rindler horizon (horizon 2)."

This new rindler sphere I just described denotes a new rindler sphere. A whole new variable.

There are 2 rindler spheres, well ellipses is more accurate. Squashed spheres then. They share an arc. The one as I drew and the one as I described. I need to add an arc to the drawing.

Thanks!

Edit:

Added pic with changes. Close enough.

It seems evident to me that MIHSC describes only the inertia component of emdrive which then enables Dr. White's ideas of thrust interactions.

Prove me wrong.
First of all thank you for going through the effort to put your ideas into pictorial form.  That is very commendable, as it much easier for people to write words.

Second, it appears to me that you favor physical (rather than mathematical) explanations.  I draw that conclusion from the notes about Casimir attraction, and for you searching for a physical interaction that will ultimately enable the movement.   I operate differently, I prefer John von Neumann's mathematical approach to physics.  One critical aspect of this approach are conservation laws.  I don't interpret the Casimir effect as an attractive force due to the quantum vacuum.  What I see in Prof. McCulloch's formulation is the assumption that a finite number of Unruh waves can fit in one or the other surfaces perpendicular to the 1 D direction of motion.  Again to me conservation of momentum is a critical law and given a change of inertia, that there must be a force (producing an acceleration) to conserve momentum is a satisfactory explanation.  The reason why this looks "unphysical" is because we are all accustomed to EEP: anything that deviates from EEP by its very nature feels unphysical.  Explaining the movement as enabling Dr. White's interactions with the Quantum Vacuum (modeled by him as a plasma) may be helpful to you but not to me, I just prefer McCulloch's explanation that it must be acted by a force to conserve momentum.  And as difficult as it maybe if forced to dispense with one or the other, I rather dispense with EEP than with conservation of momentum.  Of course, one still has to consider that the NASA, Chinese and Shawyer experiments still maybe an experimental artifact and they may not serve as a means of propulsion in outer space.

I couldn't agree more. I deal in the physical world of electronics in my daily life. Engineering, some math. You are a math guy. I hope we're both right in the end because we compliment eachother.

On the notion of MiHsC violating GR by virtue of violating the EEP.....
Did anyone notice a few pages back, where I took Dr.  McCulloch's ideas on dark matter and the inertia of particles with very very low accelerations, and wrapped that right back into General Relativity by further defining the origin of inertia as a function of time? The higher up a gravity well you are, the faster time flows. Look it up. A particle would have less inertia (resistance to acceleration if you want to call it that) over time, if it's time was running faster compared to others on very large scales. Large magnitudes of time differential effect acceleration and inertia as a consequence of spacetime. Accelerations affect inertia. Why is it such a stretch to understand there is an energy difference of potential between two clocks running different rates? Get it? Time runs slower down low. Time runs faster up high. What is low or high on a cosmic scale? MiHsC doesn't violate Relativity, it confined EEP to a different, more precise domain. The essence of Inertia is time.

Anyone wanna put math to that? Any math guys out there?


« Last Edit: 10/09/2014 06:02 pm by Mulletron »
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Offline aero

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Re: EM Drive Developments
« Reply #1817 on: 10/09/2014 05:36 pm »
So if the inertia varies within the cavity then what is to prevent a Dean drive from working like depicted in the attached sketch? Apart from interference effects.

In words, the mass rotates around a central support with high inertia at the bottom and low inertia at the top pulling the whole attached cavity downward by centrifugal force. Of course a spinning flywheel would work just as well, better in fact, but the blob of mass is easier to visualize.
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Offline Rodal

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Re: EM Drive Developments
« Reply #1818 on: 10/09/2014 05:48 pm »
So if the inertia varies within the cavity then what is to prevent a Dean drive from working like depicted in the attached sketch? Apart from interference effects.

In words, the mass rotates around a central support with high inertia at the bottom and low inertia at the top pulling the whole attached cavity downward by centrifugal force. Of course a spinning flywheel would work just as well, better in fact, but the blob of mass is easier to visualize.
McCulloch is dealing with the inertia of the electrons (in the walls) and the photons within the cavity.  His simple formula is a 1 dimensional approximation along the (proposed unidirectional) direction of motion (of the drive's center of mass), with the small and large flat surfaces perpendicular to the direction of motion.  The proposed 1-D direction of motion is along the cone's central axis, which is an axis of symmetry.

To posit a rotation as envisioned in the diagram one needs at least a multidimensional analysis and propose a reason why the photons in the cavity and the electrons in the copper walls would be executing an overall rotational motion.  In general (refer to the wave modes in the cavity, at 2 GHz the modes shapes are not executing such overall rotation but there are rotational cells of smaller scale).  If I am not mistaken the rotational cells are such that they are clockwise and counterclockwise like eddies in a fluid, to satisfy the same direction of motion at their common boundary.  As such their rotations seem to be self-cancelling.

This is a good question.  The modes have to be examined.  The Electric Field is completely confined within the cavity that acts as a Faraday cage. 
« Last Edit: 10/09/2014 06:00 pm by Rodal »

Offline aero

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Re: EM Drive Developments
« Reply #1819 on: 10/09/2014 06:01 pm »
So if the inertia varies within the cavity then what is to prevent a Dean drive from working like depicted in the attached sketch? Apart from interference effects.

In words, the mass rotates around a central support with high inertia at the bottom and low inertia at the top pulling the whole attached cavity downward by centrifugal force. Of course a spinning flywheel would work just as well, better in fact, but the blob of mass is easier to visualize.
McCulloch is dealing with the inertia of the electrons (in the walls) and the photons within the cavity.  His simple formula is a 1 dimensional approximation along the (proposed unidirectional) direction of motion (of the drive's center of mass), with the small and large flat surfaces perpendicular to the direction of motion. 

To posit a rotation as envisioned in the diagram one needs at least a 2-D analysis and propose a reason why the photons in the cavity and the electrons in the copper walls would be executing an overall rotational motion.  In general (refer to the wave modes in the cavity, at 2 GHz the modes shapes are not executing such overall rotation but there are rotational cells of smaller scale).  If I am not mistaken the rotational cells are such that they are clockwise and counterclockwise like eddies in a fluid, to satisfy the same direction of motion at their common boundary.  As such their rotations seem to be self-cancelling.

Sorry, I really wasn't addressing the EM drive at all, just the variable inertia. My rotating flywheel (or ball) is a complete mechanism in itself. It just operates within the cavity where inertia varies top to bottom.

My point being that this variable inertia is certainly counter intuitive and provides a fast track to a whole raft of new inventions.

Proof of concept anyone?
« Last Edit: 10/09/2014 06:09 pm by aero »
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