Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 1803351 times)

Offline wallofwolfstreet

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What bothers me about it is that it is merely one example, in a variety of ‘scientific’ fields, in which the universe is not behaving according to established theory and, rather than adjusting the theory to fit observations the universe is adjusted to conform to established theory.  In this case, it required that 95+% of the universe consist of ‘stuff’ for which the only evidence of its existence is the requirement that the universe conform to EXISTING theory.

This is a gross mischaracterization of dark matter and dark energy.  If you think that the only reason the vast majority of professional scientists involved in building the theoretical and experimental basis of dark matter and dark energy is because they need it to hold on to existing theory, then you're wrong.  I strongly advise you to devote some time to researching these topics.   

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Meanwhile, Dr. McCulloch has a theory, which I am equally unqualified to critique, which he claims explains observations without the requirement of unobservable, undetectable ‘stuff’.  He is dismissed as a ‘kook’ and his theory is not even given cursory consideration.  Why?  Because his theory conflicts with ‘established theory’.

Why is it that whenever someone has a theory that isn't fondled by the mainstream, the immediate accusation is that it's because the mainstream doesn't like having "established theory" contradicted?  Occam's razor: the reason no one takes McCulloch's theory seriously, is because it makes no sense.  McCulloch is one individual, who has his doctorate in oceanography, not physics, who supports MiHsC.  Can you point to literally anyone else in the physics community, fringe or mainstream, professional or not, who supports MiHsC?  If not, why? 

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  I do know though that rejecting new theories because they are in conflict with old theories, even to the point in the case of DM/DE of inventing an undetectable 95% of the universe to force the universe to conform to theory, seems to me to be a singularly unpromising method of ‘advancing science’.

You realize you are essentially accusing the tens of thousands of active researchers in cosmology that work on dark matter and dark energy on a daily basis of being sub par scientists, because you, a person who just admitted to not being qualified to critique it from a scientific perspective, don't personally like it?

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In my case that goes a long way toward explaining why I am rooting against ‘established science’ in the case of the EmDrive.  I am an aficionado of manned space travel, but unless EmDrive or something functionally equivalent is real, we ain’t goin’ nowhere and we ain’t gonna do nothin’ when we get there.  So I HOPE that it is real and that one or more of the DIY’ers demonstrate measurable, repeatable thrust after accounting for experimental artifacts.  If not, maybe the NEXT 'fringe effort' WILL work. 

Well at least that's an honest way of putting it.  You don't necessarily see the evidence of the emdrive as being strong, you just wish it were true because it would be gratifying to see all those stuffy mainstream scientists be wrong and it would be really cool to travel the solar system.

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I am certainly not qualified to critique ‘dark matter/dark energy’ from a scientific perspective.

What other perspective matters?  Critiquing a scientific theory from outside a scientific perspective is like saying you think the Mona Lisa is an artistically poor painting because Leonardo da Vinci had a bad hair cut.

Offline Star One

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What bothers me about it is that it is merely one example, in a variety of ‘scientific’ fields, in which the universe is not behaving according to established theory and, rather than adjusting the theory to fit observations the universe is adjusted to conform to established theory.  In this case, it required that 95+% of the universe consist of ‘stuff’ for which the only evidence of its existence is the requirement that the universe conform to EXISTING theory.

This is a gross mischaracterization of dark matter and dark energy.  If you think that the only reason the vast majority of professional scientists involved in building the theoretical and experimental basis of dark matter and dark energy is because they need it to hold on to existing theory, then you're wrong.  I strongly advise you to devote some time to researching these topics.   

Quote
Meanwhile, Dr. McCulloch has a theory, which I am equally unqualified to critique, which he claims explains observations without the requirement of unobservable, undetectable ‘stuff’.  He is dismissed as a ‘kook’ and his theory is not even given cursory consideration.  Why?  Because his theory conflicts with ‘established theory’.

Why is it that whenever someone has a theory that isn't fondled by the mainstream, the immediate accusation is that it's because the mainstream doesn't like having "established theory" contradicted?  Occam's razor: the reason no one takes McCulloch's theory seriously, is because it makes no sense.  McCulloch is one individual, who has his doctorate in oceanography, not physics, who supports MiHsC.  Can you point to literally anyone else in the physics community, fringe or mainstream, professional or not, who supports MiHsC?  If not, why? 

Quote
  I do know though that rejecting new theories because they are in conflict with old theories, even to the point in the case of DM/DE of inventing an undetectable 95% of the universe to force the universe to conform to theory, seems to me to be a singularly unpromising method of ‘advancing science’.

You realize you are essentially accusing the tens of thousands of active researchers in cosmology that work on dark matter and dark energy on a daily basis of being sub par scientists, because you, a person who just admitted to not being qualified to critique it from a scientific perspective, don't personally like it?

Quote
In my case that goes a long way toward explaining why I am rooting against ‘established science’ in the case of the EmDrive.  I am an aficionado of manned space travel, but unless EmDrive or something functionally equivalent is real, we ain’t goin’ nowhere and we ain’t gonna do nothin’ when we get there.  So I HOPE that it is real and that one or more of the DIY’ers demonstrate measurable, repeatable thrust after accounting for experimental artifacts.  If not, maybe the NEXT 'fringe effort' WILL work. 

Well at least that's an honest way of putting it.  You don't necessarily see the evidence of the emdrive as being strong, you just wish it were true because it would be gratifying to see all those stuffy mainstream scientists be wrong and it would be really cool to travel the solar system.

Quote
I am certainly not qualified to critique ‘dark matter/dark energy’ from a scientific perspective.

What other perspective matters?  Critiquing a scientific theory from outside a scientific perspective is like saying you think the Mona Lisa is an artistically poor painting because Leonardo da Vinci had a bad hair cut.

There are an increasing number of scientists who are having doubts about the whole concept of Dark Matter/Energy. But I suppose you will not accept that because it doesn't fit in with scientific orthodoxy. In my view one of the greatest impediments to scientific advance is cleaving too closely to orthodoxy without adopting any kind of critical questioning.


I was pleased too see for example that Pluto appears to be defying the orthodoxy of what was expected of it. Scientific observation & experimentation will always trump theory made without any practical backing.
« Last Edit: 07/30/2015 06:57 PM by Star One »

Offline rfmwguy

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Re rfmwguy Post #5685
“Ps to dm...is dark matter floobie dust?”

I am certainly not qualified to critique ‘dark matter/dark energy’ from a scientific perspective.

What bothers me about it is that it is merely one example, in a variety of ‘scientific’ fields, in which the universe is not behaving according to established theory and, rather than adjusting the theory to fit observations the universe is adjusted to conform to established theory.  In this case, it required that 95+% of the universe consist of ‘stuff’ for which the only evidence of its existence is the requirement that the universe conform to EXISTING theory.

Meanwhile, Dr. McCulloch has a theory, which I am equally unqualified to critique, which he claims explains observations without the requirement of unobservable, undetectable ‘stuff’.  He is dismissed as a ‘kook’ and his theory is not even given cursory consideration.  Why?  Because his theory conflicts with ‘established theory’. 

Is dark matter real or not?  Is Dr. McCulloch’s theory right or wrong?  Haven’t the foggiest.  I do know though that rejecting new theories because they are in conflict with old theories, even to the point in the case of DM/DE of inventing an undetectable 95% of the universe to force the universe to conform to theory, seems to me to be a singularly unpromising method of ‘advancing science’. 

In my case that goes a long way toward explaining why I am rooting against ‘established science’ in the case of the EmDrive.  I am an aficionado of manned space travel, but unless EmDrive or something functionally equivalent is real, we ain’t goin’ nowhere and we ain’t gonna do nothin’ when we get there.  So I HOPE that it is real and that one or more of the DIY’ers demonstrate measurable, repeatable thrust after accounting for experimental artifacts.  If not, maybe the NEXT 'fringe effort' WILL work.
I understand your position well. I also believe in CoM and CoE but I feel its both arrogant and misguided to assume we know everything. You will find those claiming the drive is "#$^&" like a Caltech professor did recently are very protective of the existing "body of knowledge" of physics as THEY understand it. Unfortunately for them, this creates a magnet for those who can't wait to prove them wrong. Seems they're just asking for it.

Our friend deltamass here invented the term Floobie Dust, which just sounds cool to me. As a friendly skeptic of emdrive, I asked him if dark matter was indeed floobie dust. It is all in good fun.  ;)

Offline wallofwolfstreet

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There are an increasing number of scientists who are having doubts about the whole concept of Dark Matter/Energy. But I suppose you will not accept that because it doesn't fit in with scientific orthodoxy. In my view one of the greatest impediments to scientific advance is cleaving too closely to orthodoxy without adopting any kind of critical questioning.

I was pleased to see for example that Pluto appears to be defying the orthodoxy of what was expected of it. Scientific observation & experimentation will always trump theory made without any practical backing.

Haha, like whom?  Where is the list of scientists abandoning dark matter and energy?  Can you name any of these mystery scientists? 

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But I suppose you will not accept that because it doesn't fit in with scientific orthodoxy.

I won't accept that people are having doubts?  Doubts are completely natural, I'd be surprised if people didn't have them. 
« Last Edit: 07/30/2015 07:08 PM by wallofwolfstreet »

Offline phaseshift

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I am delighted to see WarpDrive and rfmwguy present theories for the EM-Drive's thrust that warp space, especially interesting is that rfmwguy's uses a 4th spatial dimension.  In my opinion this is the only way forward if the EM-Drive is real. Along the same lines I wanted to post some thinking I’ve been doing about the EM-Drive in the hopes of creating a spark in anyone that can take it and make a roaring fire out of it. Please forgive my writing style, I can only rewrite this so many times before I grow too much older. :)

Let’s keep in mind that ‘SciFi Science’ is another name for ‘magic’ and that magic is another name for a 'sufficiently advanced technology' - and yes that was penned by a Science Fiction writer so I’m not sure how valid it is ;)

It appears to me that the EM-Drive is a miniature Alcubierre Drive, and here’s why:

1. Any solution to the EM-Drive, as I see it, will require space to be warped. Without warping space CoM and CoE will be violated - we can’t have that - and thus my excitement about Todd’s and rfmwguy's theories, though I don’t think Todd has gone far enough and I haven’t digested rfmwguy's theory adequately to comment on it,

2. The warping of spacetime needs to be positively curved at one end (the small end), and negatively curved at the large end.  Just having a gravitational gradient between the end plates isn’t enough (it might be, but probably not). This gravitational gradient does not produce thrust, it is a magnifying lens.  Keep in mind that Eagleworks may have measured a negative curvature of space inside the frustum using a laser and interferometer,

3. The warping of space will magnify any thrust that is present - Dr. White showed how and why this is the case.  Note how both the Alcubierre Drive and the EM-Drive require a push to get them going. A push that is provided by conventional physics that is then magnified by ‘unconventional' physics. With the current EM-Drive this push might be outgassing or thermal effects or a number of other things and possibly the reason it currently works less well in a vacuum,

4. So how is the gravitational gradient produced in the EM-Drive?  It appears to me that it is not the endplates themselves that are doing it, rather, it is the corners where the endplates meet the side walls of the frustum that thrust first begins to appear - sort of. The differently sized endplates are there for two reasons - 1) to contain the EM field and build up a sufficient Q, 2) create the corner angles. Regards to # 2, it is possible that a Casimir effect is present in the acute angles of the large end - creating a negative curvature of space in a toroidal shape about the large end (just like an Alcubierre Drive). As Todd’s theory proposes there is a positive mass delta at the small end plate - no Casimir effect is produced as the angle is obtuse. How is this Casimir effect achieved? - I don’t know, but perhaps evanescent waves are responsible. There have been discussions about the evanescent waves present in the corners earlier in the forum. Yes, there is some hand waving in this part :)

Recall that an Alcubierre drive does not produce thrust, it warps space, and has to be given a push - this is the main reason I'm trying to connect the two drive types.  The warped space magnifies the push and is how the drive appears to produce far more thrust (from a conventional perspective) than it would from converting input energy directly into movement.

Several people have pointed out how the EM-Drive violates CoM and CoE,  certainly I have, and I have also said that any solution must be ‘outside’ of conventional physics and that space must be warped in order to achieve thrust (that’s my position and I’m sticking with it).  When space is warped the device no longer violates CoM or CoE - you can’t extract free energy from it though you might think so.  Anyone inside the area of warped space would look around and see that everything is ‘normal’.  Their reference frame is the inside of the warp bubble - just as it looks perfectly normal to someone near a blackhole where time is slowed 90% (for example).  There is no free energy extraction possible from the outside of the warp bubble either.  From the outside of the bubble it would (at least in the mind’s eye) appear that there is lots of free energy to be extracted, but try it and you will find that you won't be able to extract it.  From an external observer’s reference the free energy is inside the bubble and to reach it you will have to expend an equal amount of energy as you will end up extracting. Just like an Alcubierre drive does not violate Einstein’s 'nothing goes faster than light' law the EM-Drive does not violate CoM or CoE for the very same reasons - the laws are by-passed by warping space. So for those that present equations that show the EM-Drive going over Unity upon reaching certain speeds I’ll respond with ‘yes, your equations are correct, but the EM-Drive gets around this because space is warped locally”.

Something to consider about #3 above.  If the EM-Drive requires a push to get it going, and spacetime is magnifying the thrust - instead of trying to reduce extraneous thrust - increase it. Yes, this moves the EM-Drive away from a propellantless device, but so what, if the conventional thrust can be magnified many many times I’ll take it over a propellantless drive that doesn’t move any day. A spacecraft based on the Alcubierre Drive is also not propellantless.

Randall/Sundrum could still play a role here - if it’s not the Casimir effect it could be warping of space due to some form of EM interactions, in the acute corners, with a very small 4th spatial dimension that moves the mass of the EM-Drive farther from the Plank/Gravity Brane - however, that would not produce a negative curvature - but would reduce the apparent mass and possibly producing enough of a gravitational gradient to magnify thrust.

Scott
« Last Edit: 07/30/2015 08:16 PM by phaseshift »
"It doesn't have to be a brain storm, a drizzle will often do" - phaseshift

Offline X_RaY

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@Rodal
1.Thanks for verification (picture Tajmar device yesterday @4,556GHz).
My calculation was verry close :)

2. impressing picture of the fractal antennas... like that
But for what is that good in the frustrum? This type of antenna will be use to get large bandwide, for multiband mobilephones for example. We don't need large BW.
What is need is ~constand impedance match in the possible drift BW if a high Q is recommend like discussed before?
 
3.
"3) We also verified that one cannot excite Transverse Electric (TE) modes with a dipole antenna, regardless of orientation or placement in the truncated cone, the mode excited by a dipole antenna is a Transverse Magnetic (TM) mode."

At the center it doesn't work.

I remember that is possible to get TE resonance with a simple dipole:
(rfmwguy posted something similar / plans for his frustrum...)
 It's most simple for TE01p. At this mode there are currents in Phi vector inside the metallic endplate, the strongest at the radius who the besselfunktion is maximal.
Place a dipole at this radius close to the plate, E-field vector in Phi direction(tangetial to the radius).
The result will be the correct mode if the cone has the correct length to catch that eigenfrequence.

Something similar is possible at the sidewall, one have to activate currents in the right direction for the mode in the wall..
of course one need a full 3D model

very interesting posts today too much to read all after long day full of work  :-[

Very nice post X_Ray.  I was thinking of potentially using a 1/10 wave loop (like the square one I posted as it could be modeled) to excite a TE mode center in either center plate. The bandwidth should be around 20-30 mhz. Thoughts?

Also won't a loop on the side wall excite either mode depending on orientation?

Would love your feedback.

Shell

garbage wording.
Can you repost a link to your setup please?
I'm a little tired today, don't wanna search...
I think up to a quater wavelength will work like you want without bigger problems.
couple the end of the loop direct to the copper( matching capacitor will also work between loops end and copper).
Dipoles very close to the wall will work also.
Picture:
In general,pace the antenna in one of the positions like in the sketch.

Yang/Shell natural frequency = 2.456 GHz for TE012 (compared to 2.494 GHz for TM113)

using

epsilon0 = 8.854187817*10^(-12)
mu0 =  0.999991(*copper*)*4*Pi*10^-7)
resistivity =  1.678*10^(-8)(*pure copper*)

Theoretical Q = 68,705 for TE012 (compared to Q  = 45,039. for TM113)
same material properties: TE012 has significantly higher Q than TM113

Difference in Q is due entirely to the electromagnetic field distribution


for other materials or impure copper scale Q by the Square Root of the ratio of the actual resistivity to 1.678*10^(-8)

I attach below:

1) TE012 Yang/Shell Contour Plot of Electric Field in Azimuthal (Circumferential) direction in the flat plane with trapezium boundaries

2)  TE012 Yang/Shell Magnetic Vector Field in the flat plane with trapezium boundaries

3)  TE012 Yang/Shell Electric Vector Field in the circular cross-section at spherical radius r=0.88 m

4)  TE012 Yang/Shell Magnetic Vector Field in the circular cross-section at spherical radius r=0.88 m

CONCLUSIONS:

1) based on the actual magnitude and directions of the electromagnetic fields in the TE012 mode it does not look that easy to excite TE012 using a dipole antenna.

2) it looks like it would be much easier to excite TE012 by using a loop antenna (it could be a square loop)


It is equal which kind of antenna will be used. ExH means there are both components forming the field. If you like use a loop :)
The activation of the field depends on the antenna, its direction and the location inside the frustum.

I have derived the theta_max Radius for the H field(TE01) of SeeShells end plates (with the help of my old dokuments).
Hope i got no mistakes with the math, please correct me if i does.
Its just effective half the way between center and max_radius.
« Last Edit: 07/30/2015 08:08 PM by X_RaY »

Offline LasJayhawk


So here is my question: can you think of another phenomenon in Nature where something will accelerate only due to internal electromagnetic fields without anything ejecting to the outside?

Well I just let go of a magnet and if flew through the air, until it came to rest against a piece of iron on the wall. Pretty sure it didn't eject anything. :)

Has anyone looked to see what kind of magnetic field is surrounding this thing? Nothing fancy, maybe how close a Boy Scout compass needs to be before it deflects?

I have considered that this is just a goofy electromagnet, and is trying to move towards the nearest piece of steel (nails in the wall, etc)

Online Rodal

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So here is my question: can you think of another phenomenon in Nature where something will accelerate only due to internal electromagnetic fields without anything ejecting to the outside?

Well I just let go of a magnet and if flew through the air, until it came to rest against a piece of iron on the wall. Pretty sure it didn't eject anything. :)

Has anyone looked to see what kind of magnetic field is surrounding this thing? Nothing fancy, maybe how close a Boy Scout compass needs to be before it deflects?

I have considered that this is just a goofy electromagnet, and is trying to move towards the nearest piece of steel (nails in the wall, etc)

Yes it did.   If your magnet attached itself to the iron wall, it was because the magnetic field of your magnet was unimpeded between the iron on the wall and the magnet.

Look at this image (you can do this by placing tiny iron fragments to display the magnetic field lines) to see the reality of what is "ejected" from the poles of a magnet:



Take a gander at the boundary conditions of the electromagnetic fields inside the microwave copper enclosure . 

Quite different from the experiment that you postulate.

The magnetic fields become eddy currents in the copper and that energy dissipates into heat, which was measured by NASA Eagleworks and correlates 100% with the theoretical prediction based on classical physics.
« Last Edit: 07/30/2015 08:17 PM by Rodal »

Offline Josave

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The latest results obtained by Matin Tajmar agrees very well with MiHsc theory of Dr. McCulloch

Below is the table you can see in his blog.  T1 is the Tajmar EmDrive model:

Expt     Q       Power     Freq.       wb        ws          L            Observed     MiHsC Predicted
                     (Watts)  (GHz)      (cm)     (cm)       (cm)          (milliNewtons)
 ---------------------------------------------------------------------------------------------------


S a      5900     850       2.45       16        12.750   15.6        16              3.84

S b    45000   1000       2.45       28        12.890   34.5        80-214       148

C a     1.1e7       10.5    1.047     22        20            3.0         9             7.34
 
J 1     32000   1000       2.45       28        12.89     34.5        214          106

J 2     50000   1000       2.45       28        12.89     34.5        315          165

B a      7320       16.9    1.933     27.94    15.88    22.86        0.09        0.23

B b    18100       16.7    1.937       "           "             "           0.05        0.57

B c    22000       2.6      1.88         "           "             "           0.06        0.11

B v     6730        50       1.937       "           "             "           0.03        0.64

T 1     20.3        700      1.44        5.41      3.85       6.86       0.02        0.019

---------------------------------------------------------------------------------------------


More details in his blog entry of 13-feb-2015. I think his theory deserves more studying, after reading his book, MiHsC seems very plausible and there is nothing of esoteric physics involved, everything is explained in terms of Casimir effect....

Online Rodal

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The latest results obtained by Matin Tajmar agrees very well with MiHsc theory of Dr. McCulloch

Below is the table you can see in his blog.  T1 is the Tajmar EmDrive model:

Expt     Q       Power     Freq.       wb        ws          L            Observed     MiHsC Predicted
                     (Watts)  (GHz)      (cm)     (cm)       (cm)          (milliNewtons)
 ---------------------------------------------------------------------------------------------------


S a      5900     850       2.45       16        12.750   15.6        16              3.84

S b    45000   1000       2.45       28        12.890   34.5        80-214       148

C a     1.1e7       10.5    1.047     22        20            3.0         9             7.34
 
J 1     32000   1000       2.45       28        12.89     34.5        214          106

J 2     50000   1000       2.45       28        12.89     34.5        315          165

B a      7320       16.9    1.933     27.94    15.88    22.86        0.09        0.23

B b    18100       16.7    1.937       "           "             "           0.05        0.57

B c    22000       2.6      1.88         "           "             "           0.06        0.11

B v     6730        50       1.937       "           "             "           0.03        0.64

T 1     20.3        700      1.44        5.41      3.85       6.86       0.02        0.019

---------------------------------------------------------------------------------------------


More details in his blog entry of 13-feb-2015. I think his theory deserves more studying, after reading his book, MiHsC seems very plausible and there is nothing of esoteric physics involved, everything is explained in terms of Casimir effect....
But so does Tajmar's results correlate with Shawyer's prediction, for that test, as Tajmar himself points out.

And McCulloch's prediction is using the wrong geometry, which is off by a factor of 2, as first shown by X-Ray.

But what about the all-important experiment in vacuum ?  Is the experiment in vacuum in McCulloch's table?

And what happens if you compare McCulloch's formula with the best estimates of geometry as shown here: http://emdrive.wiki/Experimental_Results for other tests, including NASAs test in vacuum ?

Some of them are very far off.  And there is no basis on which to say that McCulloch's prediction overall is any better than Notsosureofit's or Shawyer's,

Notsosureofit's takes into account the mode shape, the other formulas do not.  That's one important thing going for Notsosureofit's formula...

///////////

As to more studying of McCulloch's theory, not sure what we can do here, we look forward to McCulloch leading that effort, by applying his theory, for example:

1) Providing quantitative analysis to explain the much lower results in vacuum found by NASA and Tajmar than in air

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?

3) Back of the envelope calculations of this photon "acceleration" using McCulloch's method appear to falls short of the acceleration required for Unruh radiation, how is this explained ?

4) What experimental evidence is there for Unruh radiation around an EM Drive and what can researchers do to test whether this Unruh radiation is real?
« Last Edit: 07/30/2015 08:35 PM by Rodal »

Offline Tron

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And McCulloch's prediction is using the wrong geometry, which is off by a factor of 2, as first shown by X-Ray


To be fair, and not defending anyone here, if you examine McCulloch's formula you'll realize that it depends on the shape of the resonant chamber and not the size.

Online Rodal

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And McCulloch's prediction is using the wrong geometry, which is off by a factor of 2, as first shown by X-Ray


To be fair, and not defending anyone here, if you examine McCulloch's formula you'll realize that it depends on the shape of the resonant chamber and not the size.

He had several equations.  One of them depended on the ratio of the length to the diameters, so in that case the factor of 2 would not affect it, you are correct. 
However another formula did NOT depend on length as the scaling parameter.  See:  http://physicsfromtheedge.blogspot.co.uk/2014/10/mihsc-vs-emdrive-updated-table.html for the two fomulae:

F = PQ/f * ((1/w_big)-(1/w_small))              MiHsC1

F = PQ L/c * ((1/w_big)-(1/w_small))            MiHsC2  (I believe this is the one in his paper)

The first formula, MIHsC1 is very much affected by a factor of 2 in the dimensions !

Then he had this formula:

F = -PQ/c * (|sin(pi*w_small/L)|-|sin(pi*w_big/L)|)   MiHsC3

He also had a 3 D formula which was different from his first formula:

F = 6PQL/c * ( 1/(L+4wb) - 1/(L+4ws) )  MiHsC4

So that's at least four different McCulloch formulae.

Has McCulloch settled on one formula? Could you provide a link to which formula is the one that he settled on?

______

EDITED to add the four formulae
« Last Edit: 07/30/2015 10:18 PM by Rodal »

Offline X_RaY

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And McCulloch's prediction is using the wrong geometry, which is off by a factor of 2, as first shown by X-Ray


To be fair, and not defending anyone here, if you examine McCulloch's formula you'll realize that it depends on the shape of the resonant chamber and not the size.
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
« Last Edit: 07/30/2015 08:31 PM by X_RaY »

Offline Star One

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There are an increasing number of scientists who are having doubts about the whole concept of Dark Matter/Energy. But I suppose you will not accept that because it doesn't fit in with scientific orthodoxy. In my view one of the greatest impediments to scientific advance is cleaving too closely to orthodoxy without adopting any kind of critical questioning.

I was pleased to see for example that Pluto appears to be defying the orthodoxy of what was expected of it. Scientific observation & experimentation will always trump theory made without any practical backing.

Haha, like whom?  Where is the list of scientists abandoning dark matter and energy?  Can you name any of these mystery scientists? 

Quote
But I suppose you will not accept that because it doesn't fit in with scientific orthodoxy.

I won't accept that people are having doubts?  Doubts are completely natural, I'd be surprised if people didn't have them.

You were quite happy to lecture a poster on here about doing further research. So I'll turn that around and suggest if you want to know the people with alternatives to dark matter theory that you do some research on the matter.

Offline Tron

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And McCulloch's prediction is using the wrong geometry, which is off by a factor of 2, as first shown by X-Ray


To be fair, and not defending anyone here, if you examine McCulloch's formula you'll realize that it depends on the shape of the resonant chamber and not the size.

He had several equations.  One of them depended on the ratio of the length to the diameters, so in that case the factor of 2 would not affect it, you are correct.  However another formula used the wavelength as the scaling parameter.  He also had a 3 D formula which was different from his first formula. Has McCulloch settled on one formula? Could you provide a link to which formula is the one that he settled on?

I was only familiar with the 3d one here:

http://physicsfromtheedge.blogspot.co.uk/2015/02/mihsc-vs-emdrive-data-3d.html

which is F = 6PQL/c * ( 1/(L+4wb) - 1/(L+4ws) )   Obviously, putting the L inside the parenthesis makes it an adimensional factor that can go from 0 to -1. (I'm surprised he didn't do it himself and called it the "Cavity form efficiency" or somesuch)

Offline wallofwolfstreet

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You were quite happy to lecture a poster on here about doing further research. So I'll turn that around and suggest if you want to know the people with alternatives to dark matter theory that you do some research on the matter.

It's not my job to justify your statements for you.

If you feel their is some exodus of scientists away from dark matter or dark energy, prove it.  I'm not going on some wild goose chase to learn about some fact I couldn't care less about.  As a "fringe" man yourself (and I don't mean that in a disparaging way, just that you are interested in alternative theories), you know how many people believe a theory has no impact on whether or not it's true.  I know this likewise, and so
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There are an increasing number of scientists who are having doubts about the whole concept of Dark Matter/Energy.
is irrelevant. 

But I figured I'd ask to see if you could rustle up the source you got that from, or if you just made it up on the spot. 
« Last Edit: 07/30/2015 10:21 PM by wallofwolfstreet »

Offline Tron

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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.

Offline zellerium

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A bit off topic, but interesting...


Yesterday, we cut off the delivery waveguide on two of our microwaves and found that it dramatically improved our quality and s11 from our initial design (antenna inserted directly into the cylinder).

One of the waveguides came with a small piece of what feels like cardboard, but looks like it has a metallic paint or something. We haven’t been able to figure out what it is, but today we figured out it definitely influences our resonance.  Its dimensions are 4 by 2 by .015 inches.

This came out of a Hamilton Beach HB-P90D23AL-DJ microwave oven.
Does anyone know what it is?


Offline flux_capacitor

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@zellerium: the "cardboard-like square part" is a thin piece made of mica which covers the end of the waveguide in a microwave oven. Mica (as well as white Teflon) is indeed transparent to microwaves. It lets the EM waves pass through it but protects the food from being impregnated by some undesirable substance that may be emitted from the magnetron cavity, like oil or metallic particles.

This is a thought to EmDrive DIYers: maybe it is a good idea to insert a Teflon or Mica sheet in the waveguide to protect the interior of the cavity from those substances, in the same manner as food is protected in the oven.
« Last Edit: 07/30/2015 08:57 PM by flux_capacitor »

Offline rfmwguy

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A bit off topic, but interesting...


Yesterday, we cut off the delivery waveguide on two of our microwaves and found that it dramatically improved our quality and s11 from our initial design (antenna inserted directly into the cylinder).

One of the waveguides came with a small piece of what feels like cardboard, but looks like it has a metallic paint or something. We haven’t been able to figure out what it is, but today we figured out it definitely influences our resonance.  Its dimensions are 4 by 2 by .015 inches.

This came out of a Hamilton Beach HB-P90D23AL-DJ microwave oven.
Does anyone know what it is?
If it covers the waveguide, I assume it is acting as an attenuator, limiting radiation into the oven. Perhaps they began to use a higher power magnetron that the microwave was not rated for.

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