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#1740 by RFPlumber on 15 Jan, 2016 19:16
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Quote
I thought Shell only had one side connected, and the other one floating... Has she chosen the right side?
First off good luck. To address your question both of my endplates are electrically connected. The large bottom plate is soldered and then a bead of silver epoxy to seal it airtight.
The small top endplate floats is right but it floats on a Beryllium flexible gasket.
Here are a few on ebay.
http://www.ebay.com/sch/i.html?_odkw=Beryllium+Copper+EMI+Gasket+Strip&_osacat=0&_from=R40&_trksid=m570.l1313&_nkw=Beryllium+Copper+EMI+Gasket+Strip&_sacat=0
(mod corrected url)
This does several things. Allows me to keep the small endplate conductive to the frustum walls while sliding up and down inside of the tune chamber and also allows heated air out of the cavity through the gaps. The very top of the tune cavity is sealed off and I have a small airline connected to it running back down the beam to vent heated air.
I really want to be able to tune the chamber through the resonance points plotting any thrusts I get and put this cutoff or no cutoff issue to bed. This means an extended full power run. Currently I've been working on a little DC variable speed motor on the end of the micrometer at the large end to slowly slide the small plate up and down.
Good luck on your run and your data. Very nice work.
Shell
Shell,
Any chance you have a drawing of your setup? I am trying to keep a mental compilation of all the details for it based on your posts and pictures, but it would be so much easier if there were a drawing...
Thanks! -
#1741 by lvirany on 15 Jan, 2016 19:26
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As Thane Heins' patent agent and someone with a loose MIT connection to Markus Zahn, I was of course very gratified to see "Rodal" post a citation to the newly-issued US#9,230,730.
It took me some time to see how Mr. Heins' claims, though seemingly fanciful, were grounded in genuine innovation. The fact that I knew him in high school helped me to suspend disbelief.
I encourage everyone to also inspect the as-yet-unexamined patent application for the "Perepiteia" itself:
www.google.com/patents/US20140111054
Both above patent documents include competent explanations of what might be termed "the Heins effect." The complete explanation took a great deal of time and work and is an ongoing project.
Yes Virginia, there are undiscovered inventions waiting to be found by the unlikeliest of people, in the unlikeliest of places.
Les Virany BSEE MIT, Registered Patent Agent
Licensed to teach physics in the state of MA. -
#1742 by SeeShells on 15 Jan, 2016 19:30
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....
If anyone knows why this frustum should not be producing thrust then speak now or forever hold your peace.
Ladies and Gentleman, you can now make your bets. (I have already simulated mode frequency shifts for difference thicknesses of HDPE disks at the small end, so this gives a good hint as to what my own prediction for this upcoming test is…)
Here is my bet: No thrust. Why? Because I believe EmDrive effect does not exist.
And my bet, while the same, is slightly more optimistic: it seems that the only existing report to date of somebody being able to observe thrust from an RF cavity without dielectric and without using 700W ofheatDC powerRF magnetron energy is Cannae Superconducting. They have (presumably) got like 10 mN from 10W at 10M Q. Well, if the effect does exist and it scales linearly with Q then the most optimistic estimate for one operating with 30W and 10K unloaded Q is ... ~30 uN
This is most likely below the resolution of my setup.
However, I am now pretty convinced (ok, not yet but I most likely will be after the next test) that any effects on the order of ~400 mN / KW cannot be replicated under pure single freq RF power using solely information available in the public domain. Note I am not saying they don't exist
I am saying there is no compelling reason to believe that they exist as of today...
I believe it's critical to symmetrically introduce the RF into the cavity (proven here by dozens of meep simulations). Your bottom modified loop dipole is a good idea and I seriously though about using it in the smallend to feed the top mode of the TE012 but your building skills seem better than mine at doing antennas. They seemed to be to sensitive to angles and lengths to futz with them and I tried. So I just split the power up to two waveguides and let the frustum create the mode resonance of the cavity instead of forcing it.
There is some compelling evidence from EagleWorks as well from their pat tests. It's enforced by them expanding the project and going into a Blue Ribbon panel peer review with their current tests. I think they went quiet for the simple reason of the media frenzy they saw the last time and it was a smart move.
I am looking forward to your tests.
Shell -
#1743 by SeeShells on 15 Jan, 2016 19:32
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Quote
I thought Shell only had one side connected, and the other one floating... Has she chosen the right side?
First off good luck. To address your question both of my endplates are electrically connected. The large bottom plate is soldered and then a bead of silver epoxy to seal it airtight.
The small top endplate floats is right but it floats on a Beryllium flexible gasket.
Here are a few on ebay.
http://www.ebay.com/sch/i.html?_odkw=Beryllium+Copper+EMI+Gasket+Strip&_osacat=0&_from=R40&_trksid=m570.l1313&_nkw=Beryllium+Copper+EMI+Gasket+Strip&_sacat=0
(mod corrected url)
This does several things. Allows me to keep the small endplate conductive to the frustum walls while sliding up and down inside of the tune chamber and also allows heated air out of the cavity through the gaps. The very top of the tune cavity is sealed off and I have a small airline connected to it running back down the beam to vent heated air.
I really want to be able to tune the chamber through the resonance points plotting any thrusts I get and put this cutoff or no cutoff issue to bed. This means an extended full power run. Currently I've been working on a little DC variable speed motor on the end of the micrometer at the large end to slowly slide the small plate up and down.
Good luck on your run and your data. Very nice work.
Shell
Shell,
Any chance you have a drawing of your setup? I am trying to keep a mental compilation of all the details for it based on your posts and pictures, but it would be so much easier if there were a drawing...
Thanks!
I'll post you something but I've got company banging at the door. Give me a couple hours....
Standard WR340 Waveguides Coax>Waveguide 1/4 Wl antenna @2.47GHz
http://imgur.com/gzwV3yu
http://imgur.com/Kgkddmn
LENGTH-x = 0.1761 m, BIG DIA.-y,z = 0.3077 m, Small dia. = 0.1727 m
I'll dig out the drawings later.... -
#1744 by Rodal on 15 Jan, 2016 19:45
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As Thane Heins' patent agent and someone with a loose MIT connection to Markus Zahn, I was of course very gratified to see "Rodal" post a citation to the newly-issued US#9,230,730.
It took me some time to see how Mr. Heins' claims, though seemingly fanciful, were grounded in genuine innovation. The fact that I knew him in high school helped me to suspend disbelief.
I encourage everyone to also inspect the as-yet-unexamined patent application for the "Perepiteia" itself:
www.google.com/patents/US20140111054
Both above patent documents include competent explanations of what might be termed "the Heins effect." The complete explanation took a great deal of time and work and is an ongoing project.
Yes Virginia, there are undiscovered inventions waiting to be found by the unlikeliest of people, in the unlikeliest of places.
Les Virany BSEE MIT, Registered Patent Agent
Licensed to teach physics in the state of MA.
Hey Les, what a pleasant surprise, a warm welcome to the forum fantastic to see you here!
How did you find us
PS: the "Perepiteia" invention is very interesting to this forum because of the conservation of energy issues associated with EMDrive claims -
#1745 by rfmwguy on 15 Jan, 2016 20:06
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Cannae.com FYI only - A tangential type of EMDrive using non-frustum type cavity.
Their website has been down for a few weeks. Status of their website: http://www.icann.org/epp#clientRenewProhibited
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#1746 by glennfish on 15 Jan, 2016 20:12
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Ladies and Gentleman, you can now make your bets. (I have already simulated mode frequency shifts for difference thicknesses of HDPE disks at the small end, so this gives a good hint as to what my own prediction for this upcoming test is…)
Don't know how to bet, but if your datastream is like the last at 10 ms intervals, you're going to clear up a ton of uncertainties.
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#1747 by rfmwguy on 15 Jan, 2016 20:33
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I'd initially guess they'd just forgot to pay except for the icann status of "renew prohibited" per the link which means:Cannae.com FYI only - A tangential type of EMDrive using non-frustum type cavity.
Are they still in business ?
Their website has been down for a few weeks. Status of their website: http://www.icann.org/epp#clientRenewProhibited
This is not the first time that we have posts about their website being down. Website being down like this does not look good...
"This status code tells your domain's registry to reject requests to renew your domain. It is an uncommon status that is usually enacted during legal disputes or when your domain is subject to deletion."
Kind of tells me its beyond the pay status, perhaps a trade or word mark dispute. It might be that:
https://trademarks.justia.com/867/27/cannae-86727817.html
Published for opposition 8/17/15 and still current. -
#1748 by zen-in on 15 Jan, 2016 21:07
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As Thane Heins' patent agent and someone with a loose MIT connection to Markus Zahn, I was of course very gratified to see "Rodal" post a citation to the newly-issued US#9,230,730.
It took me some time to see how Mr. Heins' claims, though seemingly fanciful, were grounded in genuine innovation. The fact that I knew him in high school helped me to suspend disbelief.
I encourage everyone to also inspect the as-yet-unexamined patent application for the "Perepiteia" itself:
www.google.com/patents/US20140111054
Both above patent documents include competent explanations of what might be termed "the Heins effect." The complete explanation took a great deal of time and work and is an ongoing project.
Yes Virginia, there are undiscovered inventions waiting to be found by the unlikeliest of people, in the unlikeliest of places.
Les Virany BSEE MIT, Registered Patent Agent
Licensed to teach physics in the state of MA.
Welcome to the forum Les! I'm sure I'm not the only one who finds it is difficult to understand a physical concept by reading the patent. Are there any papers with experimental data or is this all theoretical?
I also believe there are undiscovered inventions waiting to be found, if you know where and how to look. -
#1749 by RFPlumber on 15 Jan, 2016 21:37
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I'll post you something but I've got company banging at the door. Give me a couple hours....
Standard WR340 Waveguides Coax>Waveguide 1/4 Wl antenna @2.47GHz
http://imgur.com/gzwV3yu
http://imgur.com/Kgkddmn
LENGTH-x = 0.1761 m, BIG DIA.-y,z = 0.3077 m, Small dia. = 0.1727 m
I'll dig out the drawings later....
So your RF path is something like: magnetron -> coax adaptor -> splitter (?) -> 2 coax feeds into 2 waveguides -> 2 coax to waveguide adaptors -> 2 waveguides to frustum.
It would be interesting to learn how you're dealing with the following topics:
1. Measuring (~700W ?) of forward RF power from magnetron. (I would be scared...)
2. Measuring reflected power (to detect resonance, to confirm waveguide matching, etc.)
3. Preventing any dis-integration and physical injury when your frustum is not in resonance, and you have 700W of reflected RF power... and your 2 waveguides are no longer waveguides but now are potentially resonant chambers themselves... This may explain your antenna damage - small metal pieces in the microwaveovencavity do not last long... And once those antennas fail, my understanding is that all 700W will be reflected back to magnetron...
4. Have you had a chance to measure the Q of your frustum? Have you had a chance to measure spectrum output of the magnetron? How much of the latter "fits" into the Q-defined "well"?
5. My understanding is that magnetron output is not phase-locked. Are there any concerns trying to split it into 2 halves and then rely on those to excite the mode? Wouldn't the 2 halves need to be in some form of phase relation for this to succeed?
So I take it the frustum is hermetical and there is a dedicated line for hot air? This is a very good idea. -
#1750 by Rodal on 15 Jan, 2016 22:24
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Dr. Rodal: thanks very much for correcting my misunderstanding re: frustrum wall currents, I appreciate the time you took to do so.
I could write some Wolfram Mathematica code to calculate the eddy currents in the EM Drive, but I would need to have some motivation to do it. Motivation not to spend the time to do it
Would Ohmic heating still need to reconcile with the (induced) wall currents? More directly, can you give us all the scale of the expected wall currents in a 100W RF frustrum? I'm reluctant to re-visit the back of my envelope for a while, as you might imagine. I followed the link to the post you gave, but didn't spot anything which looked like it would answer the question directly.
R.
is:
1) EM Drive cavity resonance, resonance of cylindrical and truncated cone cavities have been experimentally and theoretically addressed, and understood for a long time. Some of the finest people have been involved, including Nobel Prizes and great scientists at Bell Labs, MIT's Radiation Laboratory, the Manhattan Project and those involved in proton accelerators.
2) The electromagnetic field intensity in EM Drives experiments has not been of a magnitude for which interesting General Relativity or Nonlinear Quantum Mechanics effects are present to justify the claimed forces.
3) Andre Fuzfa's (http://arxiv.org/abs/1504.00333) paper on "How Current Loops and Solenoids Curve Space-time" requiresQuotearbitrarily large steady electric currents
Quotesince the large electric currents that can be achieved with current superconducting cables, roughly of order 10^4 A, will generate extremely weak space-time curvature, it will be necessary to amplify the signal by forcing light to perform numerous round trips in the artifi cially generated gravitational fi eld.
while the electric fields in the EM Drive, instead of being steady currents in a cable are radio-frequency waves alternating in time (at around 2 GHz frequencies) and moreovoer, the electric field magnitude in EM Drive experiments instead of being "arbitrarily large" has been small, relatively speaking. Actually, if the test performed in air exceed just 10^6 V/m, air will experience dielectric breakdown and become conductive (like lightning).
So whatever is going on in the EM Drive has to be explainable as due to the known power (less than 1kw) involved in a resonant cavity excited at ~2GHz
_____
If you have some counterarguments, to motivate one to calculate the eddy currents, please let me know
Best regards,
JR -
#1751 by RFPlumber on 15 Jan, 2016 22:56
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Dr. Rodal: thanks very much for correcting my misunderstanding re: frustrum wall currents, I appreciate the time you took to do so.
I could write some Wolfram Mathematica code to calculate the eddy currents in the EM Drive, but I would need to have some motivation to do it. Motivation not to spend the time to do it
Would Ohmic heating still need to reconcile with the (induced) wall currents? More directly, can you give us all the scale of the expected wall currents in a 100W RF frustrum? I'm reluctant to re-visit the back of my envelope for a while, as you might imagine. I followed the link to the post you gave, but didn't spot anything which looked like it would answer the question directly.
R. is:
...
<some very good arguments here>
...
If you have some counterarguments, to motivate one to calculate the eddy currents, please let me know
Or I can post a COMSOL plot of surface current density at 100W input if it helps... That recent colorful plot of surface _power_ density was for either 1W or 10W of input power (I just don't remember the settings as it was simulated a while ago)... -
#1752 by Rodal on 15 Jan, 2016 23:10
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Dr. Rodal: thanks very much for correcting my misunderstanding re: frustrum wall currents, I appreciate the time you took to do so.
I could write some Wolfram Mathematica code to calculate the eddy currents in the EM Drive, but I would need to have some motivation to do it. Motivation not to spend the time to do it
Would Ohmic heating still need to reconcile with the (induced) wall currents? More directly, can you give us all the scale of the expected wall currents in a 100W RF frustrum? I'm reluctant to re-visit the back of my envelope for a while, as you might imagine. I followed the link to the post you gave, but didn't spot anything which looked like it would answer the question directly.
R. is:
...
<some very good arguments here>
...
If you have some counterarguments, to motivate one to calculate the eddy currents, please let me know
Or I can post a COMSOL plot of surface current density at 100W input if it helps... That recent colorful plot of surface _power_ density was for either 1W or 10W of input power (I just don't remember the settings as it was simulated a while ago)...
Yes, it would be great if you could show the COMSOL plot of surface current density at 100W input -
#1753 by aero on 15 Jan, 2016 23:36
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Dr. Rodal and others -
Attached find my attempt, with SeeShell's guidance, to model the geometry of Tajmar's frustum. I have labelled the sections so that we can identify them for discussion.
I have made several guess: Like "What is the height of the feed and coupler sections?" I'm assuming that the width is 1/2 the height as is common for waveguides, and Shell extracted the section lengths from the image. I am still in doubt about the length of the WR 340 but Shell assures me that it is a commercial part and I'm using those dimensions. But the antenna doesn't seem to me to be the right distance from the end of the WR 340 being 0.021336 meters instead of 1/4 wavelength which is about 0.03 meters.
One other item in question is regarding a rectangular z-choke. Did Tajmar use one as Yang did, and if he did, where was it located?
In any event the fields are not forming quickly, if they ever will. The attached two gif's are 10 frames from one cycle at the end of a 64 cycle run. I haven't tried to make a resonance run because I think there is still some tweaks needed to the model.
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#1754 by Rodal on 15 Jan, 2016 23:44
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Dr. Rodal and others -
This is the information I'm aware of:
Attached find my attempt, with SeeShell's guidance, to model the geometry of Tajmar's frustum. I have labelled the sections so that we can identify them for discussion.
I have made several guess: Like "What is the height of the feed and coupler sections?" I'm assuming that the width is 1/2 the height as is common for waveguides, and Shell extracted the section lengths from the image. I am still in doubt about the length of the WR 340 but Shell assures me that it is a commercial part and I'm using those dimensions. But the antenna doesn't seem to me to be the right distance from the end of the WR 340 being 0.021336 meters instead of 1/4 wavelength which is about 0.03 meters.
One other item in question is regarding a rectangular z-choke. Did Tajmar use one as Yang did, and if he did, where was it located?
In any event the fields are not forming quickly, if they ever will. The attached two gif's are 10 frames from one cycle at the end of a 64 cycle run. I haven't tried to make a resonance run because I think there is still some tweaks needed to the model.
* Between the Cavity and the waveguide Tajmar used an adapter.
Following are the dimensions in the latest corrected version of Tajmar's EM Drive paper:
http://bit.ly/1h4E0RzQuoteWe iterated our design several times by consulting with R. Shawyer to be as representative as possible. Our final tapered cavity design had an
internal top radius of 38.5 mm, a
bottom radius of 54.1 mm and a
height of 68.6 mm
as well as a side entrance for the microwaves as shown in Fig. 2. The cavity was made out of three copper pieces with a wall thickness of 3 mm where the lower and middle part as well as the side flange were hard soldered using silver and the top part was able to adapt its position in order to optimize for a high Q factor. A standard WR340 waveguide was then used to connect the magnetron to the EMDrive -
#1755 by aero on 16 Jan, 2016 00:27
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Dr. Rodal and others -
This is the information I'm aware of:
Attached find my attempt, with SeeShell's guidance, to model the geometry of Tajmar's frustum. I have labelled the sections so that we can identify them for discussion.
I have made several guess: Like "What is the height of the feed and coupler sections?" I'm assuming that the width is 1/2 the height as is common for waveguides, and Shell extracted the section lengths from the image. I am still in doubt about the length of the WR 340 but Shell assures me that it is a commercial part and I'm using those dimensions. But the antenna doesn't seem to me to be the right distance from the end of the WR 340 being 0.021336 meters instead of 1/4 wavelength which is about 0.03 meters.
One other item in question is regarding a rectangular z-choke. Did Tajmar use one as Yang did, and if he did, where was it located?
In any event the fields are not forming quickly, if they ever will. The attached two gif's are 10 frames from one cycle at the end of a 64 cycle run. I haven't tried to make a resonance run because I think there is still some tweaks needed to the model.
* Between the Cavity and the waveguide Tajmar used an adapter.
Following are the dimensions in the latest corrected version of Tajmar's EM Drive paper:
http://bit.ly/1h4E0RzQuoteWe iterated our design several times by consulting with R. Shawyer to be as representative as possible. Our final tapered cavity design had an
internal top radius of 38.5 mm, a
bottom radius of 54.1 mm and a
height of 68.6 mm
as well as a side entrance for the microwaves as shown in Fig. 2. The cavity was made out of three copper pieces with a wall thickness of 3 mm where the lower and middle part as well as the side flange were hard soldered using silver and the top part was able to adapt its position in order to optimize for a high Q factor. A standard WR340 waveguide was then used to connect the magnetron to the EMDrive
The dimensions I am using, from FluxCapacitor's post give the same diameters but a greater height of 72.8 mm. Which set of dimensions do you suppose is correct?
Looking at the images in the paper from Tajmar, it looks like the cavity tested was not the same as the prototype cavity commonly illustrated and which I based the model geometry on. Assuming that the cavity imaged inside of the vacuum chamber was the one tested.
.....
aero -
#1756 by Rodal on 16 Jan, 2016 00:33
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...The dimensions I am using, from FluxCapacitor's post give the same diameters but a greater height of 72.8 mm. Which set of dimensions do you suppose is correct?
I need some time to figure it out. I'll be back with an answer during the weekend.
Looking at the images in the paper from Tajmar, it looks like the cavity tested was not the same as the prototype cavity commonly illustrated and which I based the model geometry on. Assuming that the cavity imaged inside of the vacuum chamber was the one tested. .....
aero -
#1757 by RFPlumber on 16 Jan, 2016 02:00
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Dr. Rodal: thanks very much for correcting my misunderstanding re: frustrum wall currents, I appreciate the time you took to do so.
I could write some Wolfram Mathematica code to calculate the eddy currents in the EM Drive, but I would need to have some motivation to do it. Motivation not to spend the time to do it
Would Ohmic heating still need to reconcile with the (induced) wall currents? More directly, can you give us all the scale of the expected wall currents in a 100W RF frustrum? I'm reluctant to re-visit the back of my envelope for a while, as you might imagine. I followed the link to the post you gave, but didn't spot anything which looked like it would answer the question directly.
R. is:
...
<some very good arguments here>
...
If you have some counterarguments, to motivate one to calculate the eddy currents, please let me know
Or I can post a COMSOL plot of surface current density at 100W input if it helps... That recent colorful plot of surface _power_ density was for either 1W or 10W of input power (I just don't remember the settings as it was simulated a while ago)...
Yes, it would be great if you could show the COMSOL plot of surface current density at 100W input
Ok, I created a folder where all relevant outputs (electrical and magnetic fields, surface current density and surface power losses) for one particular frustum at one specific mode (TE012) at 100W input are saved. This can likely serve as a reference for anyone wondering about "what order of magnitude <something> is inside the EmDrive cavity"? There is also a ReadMe.txt in the same folder with description.
Here's the link: https://drive.google.com/open?id=0B3jbXEyEMvU8ZEFJV0pwNUdyaEU
ReadMe.txt:
D small: 158 mm
D big: 264 mm
L_center: 204 mm
Freq: 2323.062 [MHz]
S11 (dB): -31.59
Q factror (unloaded): 75152
Dissipated Power (W): 99.27
Lumped port impedance: 52.39-0.97i
Surface current density jfyi: https://drive.google.com/file/d/0B3jbXEyEMvU8dnpWUDBGYWpESlk/view?pref=2&pli=1
(Sorry, image does not show with "Img" tag. File / resolution may be too big?)
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#1758 by Rodal on 16 Jan, 2016 02:17
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Dr. Rodal: thanks very much for correcting my misunderstanding re: frustrum wall currents, I appreciate the time you took to do so.
I could write some Wolfram Mathematica code to calculate the eddy currents in the EM Drive, but I would need to have some motivation to do it. Motivation not to spend the time to do it
Would Ohmic heating still need to reconcile with the (induced) wall currents? More directly, can you give us all the scale of the expected wall currents in a 100W RF frustrum? I'm reluctant to re-visit the back of my envelope for a while, as you might imagine. I followed the link to the post you gave, but didn't spot anything which looked like it would answer the question directly.
R. is:
...
<some very good arguments here>
...
If you have some counterarguments, to motivate one to calculate the eddy currents, please let me know
Or I can post a COMSOL plot of surface current density at 100W input if it helps... That recent colorful plot of surface _power_ density was for either 1W or 10W of input power (I just don't remember the settings as it was simulated a while ago)...
Yes, it would be great if you could show the COMSOL plot of surface current density at 100W input
Ok, I created a folder where all relevant outputs (electrical and magnetic fields, surface current density and surface power losses) for one particular frustum at one specific mode (TE012) at 100W input are saved. This can likely serve as a reference for anyone wondering about "what order of magnitude <something> is inside the EmDrive cavity"? There is also a ReadMe.txt in the same folder with description.
Here's the link: https://drive.google.com/open?id=0B3jbXEyEMvU8ZEFJV0pwNUdyaEU
ReadMe.txt:
D small: 158 mm
D big: 264 mm
L_center: 204 mm
Freq: 2323.062 [MHz]
S11 (dB): -31.59
Q factror (unloaded): 75152
Dissipated Power (W): 99.27
Lumped port impedance: 52.39-0.97i
Surface current density jfyi: https://drive.google.com/file/d/0B3jbXEyEMvU8dnpWUDBGYWpESlk/view?pref=2&pli=1
(Sorry, image does not show with "Img" tag. File / resolution may be too big?)
Thank you so much !
That's a really great job
Maximum current at 100 W is 498 Amp/meter. The mode shape is TE012, the current is due to the magnetic field. This current is orders of magnitude smaller than required (in Andre Fuzfa's paper) to produce significant space-time curvature.
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#1759 by RFPlumber on 16 Jan, 2016 02:26
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Dr. Rodal and others -
Attached find my attempt, with SeeShell's guidance, to model the geometry of Tajmar's frustum. I have labelled the sections so that we can identify them for discussion.
...
Since you brought up Tajmar, and I was just re-reading that paper a couple days ago, do you actually think / believe that he was truly getting any abnormal thrust? Why?
IMHO, his conclusions and reasoning are on par with Shawyer, where Shawyer at least gets a discount as a promoter / inventor / (or a great troll). Tajmar in turn is supposed to be an unbiased critical thinker... yet he follows the same flawed logic of "here's a difference in some thermal force... it must be thrust... now try this in vacuum... the thermal force is gone completely along with its difference which used to be our thrust... this does not teach us anything though because now there is some other force observed which is also different, and so the difference must again be thrust as we just can't think of anything else".
This is most likely below the resolution of my setup.
I am saying there is no compelling reason to believe that they exist as of today...
is: