Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 1876767 times)

Offline X_RaY

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Thats why it is a little bit freaky to me opinion. That can only be true for modes with p value equal to zero, and only if the diameter fits frequency. The angle alone tells nothing. again IMHO

Well, the formula also contains Q and if you derive it from the cavity's size ultimately it will contain the length. But if you're supplied with a Q and the dimension then the formula works even if all the dimensions are cut by the same factor.

Ultimately it doesn't matter IMHO because it predicts the thrust should start immediately after turning the magnetron, it should be proportional to the power and it should end as soon the magnetron is turned off. Since none of those are true, so either the results come from experimental error and they are useless, or they disprove the theory. Time to go back to lurking.
I have to agree in at this point. From that viewpoint it's true, Q depends on the dimensions. Undersized dimensions leads to Q-->0 and no thrust at all.
And you are right again, we need much more experimental data to confirm. futurewise i hope we will see who is right and whats the matching model.
Nobel winks to the one who's right  ;) ::)

Offline qraal

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On Dark Matter and Dark Energy, as a watcher of astrophysics for the last ~25 years I know for a fact that multiple theories exist as to their natures. Everything from geometry, topology, higher-dimensions, neutrino physics, exotic bosons and so forth have ALL been proposed and discussed. There are multiple Modified Gravity theories out there, such as Milgrom's MOND, Moffat's MoG, and others, like McCulloch's.

The problem with any comprehensive theory is getting all the data points to marry up. This is not an easy thing because no researcher can be aware of ALL the relevant observations.

So enough name-calling. Look around for a theory and come up with an observational test. Multitudes of Dark Matter theories have been cast aside due to the latest Planck and Supernova data. Think up a new test and do some science.

Offline SeeShells

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...
Interestingly enough Doc it doesn't agree with the data published about thrusts. Is the data from the Yang tests totally bogus? Or we don't have the matter of the RF injection correct yet?

I'd be wondering what your stress / poynting vector analysis is really showing? As of now it is only showing a asymetrical differential of stress levels from one end vs the other.  What are you looking for your asymmetrical stress figures to do I guess would be the question?

Right now I can take a enclosed can of air, put a air pump in it blowing at one end and the can sits still, but the pressure is higher at one end vs the other. If your saying that the increased stress in one end compresses and acts like a gravity induced gradient at that end and that causes the can to "squirt" along in it's own micro gravity well trying to equalize itself than that's a gravity warp drive.

shell

These are my views on the subject, submitted for whatever little (or nothing :) ) they may be worth. 

I submit them now, since you still have time to change the geometry of what you are going to test, and you may want to consider the following points in selecting your geometry.

<<Interestingly enough Doc it doesn't agree with the data published about thrusts. Is the data from the Yang tests totally bogus?>>

1) My statement above that the net force is zero for Yang/Shell is based on a completely different program using the energy-momentum covariant tensor in General Relativity.  This program is NOT the program that processes the Meep output to come up with the stress tensor and forces. Not based on the Meep runs

2) The Yang-Shell geometry should not be assumed to be the geometry used by Yang in her tests 
I should know, since I was the one that calculated the Yang/Shell geometry as the best estimate of her dimensions based on her early theoretical paper, and then placed those dimensions in the EM Drive wiki (explaining where they came from). Those dimensions were a best effort at inferring what the geometry was in one of her earlier papers:

a) Yang has several papers, the geometry for which Yang/Shell is based on is from a different paper where she  reports the highest forces reported.  The assumption that the geometry applies to both is just an assumption.

b) Yang does not explicitly give all the dimensions of her frustum.   Tajmar gave the dimensions for his EM Drive and it turns out that they were off by a factor of 2.  It is quite possible that something was lost in translation and the dimensions of her frustrum are different.  The geometry in her drawings looks quite different than the geometry assumed in Yang/Shell.  Her drawings show shorter length and a much larger cone angle than the cone angle in Yang/Shell.

c) IMO I think that conducting experiments based on the Yang/Shell geometry is more risky because:

c1) The Yang/Shell geometry was not provided by Yang.  Better to use a geometry provided by one of the researchers.  For example the geometry provided by NASA, which we know 100% as to being the true geometry being tested.

c2) The Yang/Shell geometry is the closest to a cylinder, having the smallest cone-angle and the largest distance between the small base and the apex of the cone.  I would use a geometry having the small base much closer to the apex: the NASA geometry or the Shawyer Demonstrator

c3) the Meep runs and my separate runs show the NSF-1701 geometry as more sensitive to test than the Yang/Shell geometry.  The Meep runs show NSF-1701 to be much more sensitive to antenna placement: very different behavior of NSF-1701, force orientation when antenna is placed at one end vs the other end.  My separate computations of Yang/Shell show it to be very close to a cylinder in its behavior, self-balanced force distribution.

c4) Based on the following formulas, the Yang/Shell geometry should be the one producing lowest thrust because:

c4A) Marco Frasca General Relativity derivation: the closest to the vertex the better.  Yang/Shell is the geometry furthest away from vertex of the cone

c4B) Todd "WarpTech" Zang and Fan paper: critical parameter is kr.  Yang/Shell has highest kr, which is worse, according to the theory

c4C) McCulloch and Notsosureofit thrust is highly dependent on the difference between the radii of the bases.  Yang/Shell is the closest to a cylinder: should generate the least thrust.

<<I'd be wondering what your stress / poynting vector analysis is really showing? As of now it is only showing a asymetrical differential of stress levels from one end vs the other.  What are you looking for your asymmetrical stress figures to do I guess would be the question? >>

The stress analysis based on the Meep runs is completely independent of the Poynting vector analysis.  The stress analysis is not at all based on the Poynting vector. 

What is more intuitive to look at are the forces calculated and displayed.  The forces are the integral of the normal stress over the cross-sectional areas.  Forces is what people talk about when discussing the EM Drive.  It is most important to understand what the forces are, how they behave vs. time and how they confirm or nullify the very simplified theories that are being thrown around.

<<Right now I can take a enclosed can of air, put a air pump in it blowing at one end and the can sits still, but the pressure is higher at one end vs the other>>

The air pressure should not be higher at one end than the other (at least in steady state, which I expect to be rapidly reached).  The equilibirum pressure should be uniformly distributed inside, no matter what the shape.  PV = nRT.  I don't understand the thought-experiment as to why the air pressure varies on the inner surface of the air can.

I can show that if one has uniform pressure inside an EM Drive, the normal stress (which is the same thing as pressure) being constant on the inner surfaces, translates to a balanced zero net force.  This is NOT what the Maxwell's equations solutions show.  The electromagnetic fields do NOT result in a uniform pressure on the inside.

IMHO based on the analysis, and as discussed above the NSF-1701 geometry is the one I would test because it has the same diameters as the NASA frustum and the one tested by Iulian Berca, and because the Meep analysis shows it to be more sensitive, while the Yang/Shell geometry is unknown whether it is representative of any EM Drive tested by Yang, and the computer results shows it to be much less sensitive, and its geometry is much closer to a cylinder, and has the small base very distant from the vertex.

Since rfmwguy is testing a geometry close to NASA, to be complementary, and since we don't quite know the Yang geometry, but we seem to have a better fix on the Shawyer geometry (from TheTraveller's communication with Shawyer) I would probably choose Shawyer's Demonstrator as the geometry, based on present information, IMHO.  :)

SeeShell, I think you have a fabulous testing set-up and testing approach, that's why I spent this time in giving you this lengthy opinion.
Dr. Rodal, Thank you for taking the time to detail out the what and why of the Yang model and to explain what your stress calculations are made of I was never sure as there are so many .
Gravitational stress-energy tensor
Electromagnetic stress-energy tensor
Acceleration stress-energy tensor
Pressure stress-energy tensor
Post-Marital Stress Field

As to the dimensions of the Yang model I would agree on some points, but behind it I have a theory I need to follow through with that I've never mentioned here and it's one reason it really is a split cavity and that idea goes back when I first joined and in some tests done by EagleWorks. The things I can get from Yang's (6 degree sidewall) is a very high Q, the variable geometry of the Hexagonal endplates, and the ability to support different smaller plates along the cavity exciting different modes wins over the quest for the all mighty thrust. Don't forget I'm for the data and there is no bad data.

I've put a lot of effort to build a test stand that is not cavity specific and will have the ability to test more than one design. This isn't (for me) a one night stand hanging a cavity on the shower curtain rod to test for maximum thrust.

I realize you have a idea of what you think is causing directional thrust and may be working on a paper or two and that gives me hope.  I have a lot of respect for your deep knowledge of how things work and how you (others here too) can simply spew out formula's on the fly simply amazes me. It takes me a while to digest and decode all of it sometimes.

I've got company again so I'll fill this in some more later. Thanks again.

shell

ERROR!
Fixed
 BBL
« Last Edit: 07/30/2015 10:45 PM by SeeShells »

Offline Josave

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2) Explaining what is the "acceleration" (and corresponding inertia modification) of photons inside the EM Drive.  What is accelerated?  If photon travels at c, nothing is accelerated.  Is he using the group velocity? the phase velocity? why?


To help in this question it deserves a look the Gerald Kaiser work "Electromagnetic inertia, reactive energy and energy flow velocity" http://iopscience.iop.org/1751-8121/44/34/345206/ and subsequent works by others easy to track in Thomson Reuters WoS.

The key is to look at the process of reflection itself, giving rise to a non trivial field configurations, as Kaiser pointed out in his 1994 book about electromagnetic wavelets. At that time he suggested applications of his wavelets to radar and scattering.

Maybe a good starting point to face EM Drive challenge is to characterize a cavity by irradiating it with wavelets instead of sinusoidal waves...

But there is no way to transmit wavelets, unless using a extremely wideband linear amplifier and antenna (fractal antenna?). Well some tentative of building these amplifiers do exist: http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6851224 . Although not viable to manage high power due to low efficiency, can be a good starting point to create an arbitrary field distribution regardless of cavity shape and size and study more on electromagnetic inertia and ultimately test the Kaiser and McCulloch theories.




Offline Devilstower

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Wouldn't any theory of EM drive that involves a fourth spatial dimension one that's not infinitesimal necessarily place us in ultrahyperbolic spacetime? Which I've always thought was a rather bad spot for physical constructs dependent on consistent laws. That was always my understanding going back to Klein. No extra spatial dimensions for you! Not unless those dimensions are bound in a compact manifold making them about as easy to access as other parts of the multiverse.

But hey, I've got my own heresies. I'm still a fan of the idea that dark matter is just probabilistic gravity leakage across branes rather than some invisible stuff in own universe. It notonly seems neater that way, it blows open fun doors in information theory.

(Note: this from a guy whose degrees are biology and geology. No one should allow this post to sway their physics opinions one Planck length.)



Offline deltaMass

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Somebody asked if anyone could cite a device that accelerates propellantlessly, and of course the answer was given (to precis and generalise the answer) that an external field often does the trick. Let me riff off that observation in the context of the Lorentz force.

The scalar expression (I won't bother with cool vector notation because it's Thursday) is simply
F = B*I*L
where F=force (N), B=magnetic field (T), I=current (A), L=conductor length (m).
We use the right-hand rule to deduce the direction of F given (B, I along L). For max effect, B is at right angles to I,L (it's a cross-product I L^B).
So that's all just a backgrounder for interested neophytes, and very cursory.

It can be easily shown that, for any closed system of conductors looping current in an external B-field, the net Lorentz force in any direction is identically zero. Were that not the case, I hazard a guess that our current transportation tech would look very different (and doubtless much cooler). But alas 'tis not thus.

Not one single EmDrive experiment to date is fully self-contained. There are wires entering and exiting the apparatus in all cases. So when you draw your virtual "force integration box" around such apparatuses, you will get a net force (however large or small) because the current source at the other end of those wires isn't in your box. This is standard physics and should come as no surprise. It is also why any EmDrive you test should be fully boxed, should run on batteries inside that box, and have no trailing wires outside that box. Yes, I'm a broken record  ::)

Let's run a sample calculation for order-of-magnitude purposes.
The Earth's field is on order 5*10-5 T
Let's peg the sort of forces being reported as on order 50 uN = 5*10-5 N
If this force is all due to the experimental artifact of a Lorentz force, then
F/B = I*L = 1 Amp-metre
That's not a lot, is it, considering the sort of dimensions and currents we're talking about re. EmDrives?
And it's easy to ask that this figure be a lot lower when the value of B is jacked up to represent an ambient magnetic field due to other current-carrying conductors in the vicinity. So we see that

It's quite easy to get Lorentz forces comparable to the measured thrusts.

Cannae is the oddball here. Fetta's simulator, an expensive professional piece of kit (whose name currently escapes me) calculates a net Lorentz force inside his cavity that is non-zero. This is a rather mysterious result, since we are talking about a closed system of currents. Last I checked, he didn't understand it, the simulator bods didn't understand it, and I for sure don't understand it.

It might be instructive for the MEEPers to take a look at this domain of behaviour.

Lastly, I have not studied how the Lorentz force transforms under SR and GR. I will leave that as an open question.


Offline QuantumG

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Combined with a setup that encourages ratcheting, just about any force will do.
Jeff Bezos has billions to spend on rockets and can go at whatever pace he likes! Wow! What pace is he going at? Well... have you heard of Zeno's paradox?

Offline deltaMass

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Post-Marital Stress Field is my favorite :)

that would be a great title for a paper :)
Tell me about it!

Offline martinc

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don't know if this is of interest/help
contains pictures of particle accelerator rf cavities.. they're very round
also interesting comment about ion's injected into it.. looks like the author's friend is quite knowledgable would be nice to see him write a follow up as his info is now quite out of date..

http://arstechnica.com/science/2014/08/dont-buy-stock-in-impossible-space-drives-just-yet/

martin
« Last Edit: 07/30/2015 10:22 PM by martinc »

Offline phaseshift

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Wouldn't any theory of EM drive that involves a fourth spatial dimension one that's not infinitesimal necessarily place us in ultrahyperbolic spacetime? Which I've always thought was a rather bad spot for physical constructs dependent on consistent laws. That was always my understanding going back to Klein. No extra spatial dimensions for you! Not unless those dimensions are bound in a compact manifold making them about as easy to access as other parts of the multiverse.

But hey, I've got my own heresies. I'm still a fan of the idea that dark matter is just probabilistic gravity leakage across branes rather than some invisible stuff in own universe. It notonly seems neater that way, it blows open fun doors in information theory.

(Note: this from a guy whose degrees are biology and geology. No one should allow this post to sway their physics opinions one Planck length.)

Read up on the Randall/Sundrum theory that places a short finite length dimension between our brane and a gravity brane, attempting to explain why gravity is so relatively weak.
"It doesn't have to be a brain storm, a drizzle will often do" - phaseshift

Offline wallofwolfstreet

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Somebody asked if anyone could cite a device that accelerates propellantlessly, and of course the answer was given (to precis and generalise the answer) that an external field often does the trick. Let me riff off that observation in the context of the Lorentz force.

The scalar expression (I won't bother with cool vector notation because it's Thursday) is simply
F = B*I*L
where F=force (N), B=magnetic field (T), I=current (A), L=conductor length (m).
We use the right-hand rule to deduce the direction of F given (B, I along L). For max effect, B is at right angles to I,L (it's a cross-product I L^B).
So that's all just a backgrounder for interested neophytes, and very cursory.

It can be easily shown that, for any closed system of conductors looping current in an external B-field, the net Lorentz force in any direction is identically zero. Were that not the case, I hazard a guess that our current transportation tech would look very different (and doubtless much cooler). But alas 'tis not thus.

Not one single EmDrive experiment to date is fully self-contained. There are wires entering and exiting the apparatus in all cases. So when you draw your virtual "force integration box" around such apparatuses, you will get a net force (however large or small) because the current source at the other end of those wires isn't in your box. This is standard physics and should come as no surprise. It is also why any EmDrive you test should be fully boxed, should run on batteries inside that box, and have no trailing wires outside that box. Yes, I'm a broken record  ::)

Let's run a sample calculation for order-of-magnitude purposes.
The Earth's field is on order 5*10-5 T
Let's peg the sort of forces being reported as on order 50 uN = 5*10-5 N
If this force is all due to the experimental artifact of a Lorentz force, then
F/B = I*L = 1 Amp-metre
That's not a lot, is it, considering the sort of dimensions and currents we're talking about re. EmDrives?
And it's easy to ask that this figure be a lot lower when the value of B is jacked up to represent an ambient magnetic field due to other current-carrying conductors in the vicinity. So we see that

It's quite easy to get Lorentz forces comparable to the measured thrusts.

Cannae is the oddball here. Fetta's simulator, an expensive professional piece of kit (whose name currently escapes me) calculates a net Lorentz force inside his cavity that is non-zero. This is a rather mysterious result, since we are talking about a closed system of currents. Last I checked, he didn't understand it, the simulator bods didn't understand it, and I for sure don't understand it.

It might be instructive for the MEEPers to take a look at this domain of behaviour.

Lastly, I have not studied how the Lorentz force transforms under SR and GR. I will leave that as an open question.

There is a common experiment to illustrate this principle.  All you need is:
a battery
two lengths copper wire
salt
water
some floaty bits (optional)

Dissolve the salt in the water.  Connect one length of the copper wire to one of the batteries electrodes and place it in the water.  Do the same with the other length of the copper wire and other electrode, so that both ends of the wires immersed in the water are a short distance apart.  If you sprinkle those floaty bits in the water between the copper wires, you'll notice they all move in the same direction.  If you have a big battery and make a loop with your wire, you can even see the water move without any aid.  This is because the lorentz force acting on the ions in the salt water (the ions have velocity from being propelled by the battery and interact with the magnetic field from the rest of the circuit) drive them all in the same direction, and the ions transfer momentum to the surrounding water molecules.  It's basically a poor man's electromagnetic pump.

Point is, the lorentz force on a free moving portion of an electric circuit (such as the ions in the water, or the wires on an emdrive measuring apparatus) is none trivial, and can be seen with the naked eye.     

Offline TheTraveller

Quote from: deltaMass
It is also why any EmDrive you test should be fully boxed, should run on batteries inside that box, and have no trailing wires outside that box. Yes, I'm a broken record ;)

Fully agree.

Plus be tested on a rotary test rig as static testing can't deliver accelerative data.

Yes, I'm also a broken record :)
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline Rodal

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Continuing from this post:
http://forum.nasaspaceflight.com/index.php?topic=37642.msg1411085#msg1411085

aero re-run, at my request, NSF-1701 with the antenna at the small base, to confirm whether the previous results posted here:
http://forum.nasaspaceflight.com/index.php?topic=37642.msg1406062#msg1406062

(which are so at odds with the Yang/Shell results with the antenna at either end and with the NSF-1701 with the antenna at the big end) were correct.

I confirm that the previous results (http://forum.nasaspaceflight.com/index.php?topic=37642.msg1406062#msg1406062) were correct.

In order to save bandwidth, I am not posting the stresses at the small and the big base (although the new results contain a few more time slices).  However I am posting here the:

EM DRIVE FORCE vs. TIME

Because this new run contains longer amount of information through time (3 extra times slices).
Antenna perpendicular to longitudinal direction placed near the Small Base for NSF-1701

Compare with
http://forum.nasaspaceflight.com/index.php?topic=37642.msg1411071#msg1411071

which are the results for the antenna at the Big Base of NSF-1701

The results shown here (NSF-1701 with antenna near the small end) are the only Meep runs that show a force directed from the small base to the big base. All the other Meep results (NSF-1701 with antenna at big end and Yang/Shell regardless of antenna placement) show a force in the opposite direction, from big end to small end.

It will be exciting to see the NSF-1701 experiment run with the antenna at either end.  These computer runs show that the behavior of NSF-1701 is fundamentally different from Yang/Shell as NSF-1701 force changes direction according to antenna placement.

Regardless of how one interprets this, one thing is clear:

NSF-1701 (the NASA and the Iulian Berca geometry) has a completely different stress (and force) distribution according to where one places the antenna.

Quote from: aer
NSF-1701 - 245x261x261
This is the final summary output from the log file.
run 0 finished at t = 13.054 (6527 timesteps)
Total number of slices 14, the last 14 of 32 full cycles, or periods at 0.1 period intervals. That is, at 30.7, 30.8 and so forth to 32.0 periods of the drive center frequency.
Number of time steps, 6527 and total meep time = 13.054 time units.

Quote from: aero
Same antenna, 58 mm in the y direction, Ez excitation.

(set! antlongx 0)                               ; direction vector of dipole antenna SI units
(set! antlongy 0.058)                           ; = 58 mm
(set! antlongz 0)
« Last Edit: 07/30/2015 11:39 PM by Rodal »

Online RonM

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Wouldn't any theory of EM drive that involves a fourth spatial dimension one that's not infinitesimal necessarily place us in ultrahyperbolic spacetime? Which I've always thought was a rather bad spot for physical constructs dependent on consistent laws. That was always my understanding going back to Klein. No extra spatial dimensions for you! Not unless those dimensions are bound in a compact manifold making them about as easy to access as other parts of the multiverse.

But hey, I've got my own heresies. I'm still a fan of the idea that dark matter is just probabilistic gravity leakage across branes rather than some invisible stuff in own universe. It notonly seems neater that way, it blows open fun doors in information theory.

(Note: this from a guy whose degrees are biology and geology. No one should allow this post to sway their physics opinions one Planck length.)

Read up on the Randall/Sundrum theory that places a short finite length dimension between our brane and a gravity brane, attempting to explain why gravity is so relatively weak.

Ah, string theory, or M theory if you prefer. Eloquent math, but less experimental evidence than EM drives.

Sorry, but until proponents of string theory can come up with some experiments that can be done to confirm their predictions, string theory is more philosophy than science.

Offline deltaMass

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@Rodal:
Clearly your net force over time has a DC component, which means a time-averaged measurement would return a nonzero reading. Thus a suggestion: plot the time average instead, cycle by cycle. That's a useful distillation of your data.

Oh, and make sure us non-MEEPers can read off Newtons and seconds!
« Last Edit: 07/30/2015 11:25 PM by deltaMass »

Offline Rodal

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@Rodal:
Clearly your net force over time has a DC component, which means a time-averaged measurement would return a nonzero reading. Thus a suggestion: plot the time average instead, cycle by cycle. That's a useful distillation of your data.
What specific method would you prefer to do that?
Using a moving average would imply a time lag of one cycle.  Would you plot the moving average showing that full time lag? Would you center it (so the time lag would be 1/2 a cycle)?

Non-parametric,  and other averages are possibilities but they all imply arbitrary conditions at the ends.



Oh, and make sure us non-MEEPers can read off Newtons and seconds!

The vertical axis is in Newtons already (for a power input of 43 watts if I recall correctly).  It could also be plotted as Newtons/Watt.  Is that what you would prefer?
« Last Edit: 07/30/2015 11:38 PM by Rodal »

Offline Prunesquallor

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Wouldn't any theory of EM drive that involves a fourth spatial dimension one that's not infinitesimal necessarily place us in ultrahyperbolic spacetime? Which I've always thought was a rather bad spot for physical constructs dependent on consistent laws. That was always my understanding going back to Klein. No extra spatial dimensions for you! Not unless those dimensions are bound in a compact manifold making them about as easy to access as other parts of the multiverse.

But hey, I've got my own heresies. I'm still a fan of the idea that dark matter is just probabilistic gravity leakage across branes rather than some invisible stuff in own universe. It notonly seems neater that way, it blows open fun doors in information theory.

(Note: this from a guy whose degrees are biology and geology. No one should allow this post to sway their physics opinions one Planck length.)

Read up on the Randall/Sundrum theory that places a short finite length dimension between our brane and a gravity brane, attempting to explain why gravity is so relatively weak.

I seem to recall Randall had proposed some CERN experiments to watch for momentum being transferred to/from extra dimensions. Does anyone know if those are still on the books?
Retired, yet... not

Offline deltaMass

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@Rodal:
N/W vertically is good. As for the preferred averaging window, clearly it must be two Pi radians in length or an integer multiple thereof. The phase offset will only make a second order difference.


I assume what you're plotting at the moment is a highly-zoomed snapshot of initial transient behaviour, and that if we zoomed right out we'd see this time averaged apparent thrust average plus and minus to zero and settle to zero asymptotically as time->infinity.
« Last Edit: 07/31/2015 12:09 AM by deltaMass »

Offline deltaMass

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Remember Lifters? They drove the woo community nutso with excitement until it was discovered they worked on an ion wind principle. But this didn't prevent every crackpot theorist with internet access chiming in with their pet theories. What is interesting is how these folks responded after it was discovered that the Emperor had no clothes. They didn't. They just walked away, silently, trailing their tattered mathematics behind them.

Now, if you have a theory that definitively predicts EmDrive thrust, and it is later shown that no such thrust exists because all measurements are experimental artifacts, what are you going to say about your theory, now clearly wrong? What suddenly changed to make it wrong? - nothing changed in the mathematics! Will we see any post hoc explanations?  Will theories be publicly abandoned? Usually this is never the case.

In an ideal world, the faulty assumptions are isolated, identified and discussed.
« Last Edit: 07/31/2015 12:24 AM by deltaMass »

Offline SeeShells

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Right now I can take a enclosed can of air, put a air pump in it blowing at one end and the can sits still, but the pressure is higher at one end vs the other. If your saying that the increased stress in one end compresses and acts like a gravity induced gradient at that end and that causes the can to "squirt" along in it's own micro gravity well trying to equalize itself then that's a gravity warp drive.

shell

Which is a hypothesis that's been covered several times in these threads....

Back on for a bit. That is why I brought it up again. In the case of a closed cavity using air, it simply cannot disappear into another form or change it's normal mater attributes so as to not be effected buy the pressure differentials in the cavity. Well I could block off one end and pump it up but when the barrier is removed it will equalize.
Here is a thought.
Now I do it with cavitating EM waves in a asymetrical cavity creating at one end high stress and wave pressures (because of the Q of the cavity) and the waves will then decay (because of the shape and nature of the cavity) into evanescent waves imparting their extraordinary spin and momentum into the walls of the cavity (and surrounding air) but it's unlike pressurized air, that imparted of spin and momentum of an evanescent decay cannot return and if I understand the equations well enough it's not all converted into heat.
Just a hot tub thought.

Shell

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