-
#3140 by Bob Woods on 25 Feb, 2016 15:05
-
http://blog.stephenwolfram.com/2015/12/what-is-spacetime-really/
Thanks a lot Doc! This blog of Dr. Wolfram is absolutely fascinating to me. The concept of a network approach to the organization of the universe is intriguing. -
#3141 by rfmwguy on 25 Feb, 2016 15:16
-
New from Mike MCullough today:
The Casimir effect, MiHsC, & Emdrive
http://physicsfromtheedge.blogspot.com/2016/02/the-casimir-effect-mihsc-emdrive.html
-
#3142 by Rodal on 25 Feb, 2016 16:25
-
New from Mike MCullough today:
The Casimir effect, MiHsC, & Emdrive
http://physicsfromtheedge.blogspot.com/2016/02/the-casimir-effect-mihsc-emdrive.html
He writesQuote from: Mike MCulloughIn the emdrive then the supercharged zero point field in the copper cone is more energetic at the wide end
What does "supercharged zero point field in the copper cone is more energetic at the wide end" mean? if the zero point field is zero point, how can it be more charged at one end than the other? if the zero point field is higher energy at one end, then is it no longer a zero point field?
Conversely, is McCulloch arguing for a Quantum Vacuum that is not immutable and non-degradable as commonly accepted, but is McCulloch instead arguing for a mutable and degradable Quantum Vacuum with a number of energy points, so there is no universal zero point, as argued by Dr. White et.al. ?
_________________
Also, the discussion in this image:
appears to consider only one mode shape, which is NOT the mode shape tested by Shawyer, or by White, or by Yang.
Energy density apparently shown by McCulloch, similar to mode shape TE011, which is NOT AT ALL the mode shape tested by Shawyer, Yang or White: (but later on, he compares his prediction vs. the experiments of Shawyer and NASA, who used different mode shapes ! )
________________
Energy density for mode shape TE012, which is the mode shape tested by Shawyer for his Demonstrator, and by Yang in her experiments:
________________
Energy density for mode shape TE013, which is the mode shape tested by Shawyer for his Flight Thruster, according to TheTraveller, and it is the mode shape nowadays recommended by Shawyer, according to TheTraveller:
________________
The mode shape does not appear in McCulloch's equations (at least it does not appear in the McCulloch equations I have seen).
By contrast, the mode shape appears explicitly in Notsorureofit's formulation, see:
http://emdrive.wiki/@notsosureofit_Hypothesis
How come there is no mode-shape dependence in McCulloch's equations
-
#3143 by Monomorphic on 25 Feb, 2016 16:42
-
How different a frequency for resonance with flat plates vs spherical ends ?
For what spherical radii? for what cone half-angles?
I would have to run another frequency sweep on the flat end frustum to know how different the frequency for resonance is. That will take a couple of hours.
This is what I have for dimensions:
Large end Spherical radius: 30 cm
Large end diameter (same as flat end frustum): 22.96 cm
Side wall length (same as flat end frustum): 18.3569 cm
NOTE: This is different than flat-end frustum total height, which is: 16.968 cm
Small end Spherical radius: 11.634 cm
Small end diameter (same as flat end frustum): 8.904 cm
There is probably a sweet spot in spherical radius. I can be on one end of that, but I think I am testing a moderate curve - nothing too extreme.
-
#3144 by dustinthewind on 25 Feb, 2016 16:46
-
New from Mike MCullough today:
The Casimir effect, MiHsC, & Emdrive
http://physicsfromtheedge.blogspot.com/2016/02/the-casimir-effect-mihsc-emdrive.html
He writesQuote from: Mike MCulloughIn the emdrive then the supercharged zero point field in the copper cone is more energetic at the wide end
What does "supercharged zero point field in the copper cone is more energetic at the wide end" mean? if the zero point field is zero point, how can it be more charged at one end than the other? if the zero point field is higher energy at one end, then is it no longer a zero point field?
Conversely, is McCulloch arguing for a Quantum Vacuum that is not immutable and non-degradable as commonly accepted, but is McCulloch instead arguing for a mutable and degradable Quantum Vacuum with a number of energy points, so there is no universal zero point, as argued by Dr. White et.al. ?
...
If there were a gradient in the quantum vacuum energy. Similar to how two plates close to each other block certain energy levels of light from existing between the plates, then is it possible that gradient in the vacuum energy levels could modify the relativistic mass of photons inside the cavity, such that when bouncing against one wall they exchange momentum differently than when bouncing against the other walls? I suspect the effect, if it exists, would red-shift energy out of the light similar to how https://en.wikipedia.org/wiki/Photonic_laser_thruster will red shift light, but inside a cavity.
Some part of me wonders if gravity could be a similar effect which results from matter inducing a gradient in the quantum vacuum. Maybe by matter being a Fourier sum of many frequencies, https://en.wikipedia.org/wiki/Fourier_series -
#3145 by CW on 25 Feb, 2016 17:03
-
I like to think of the ZPF as a GND or reference plane, like in electronics. Perhaps the idea is something as a ground loop carrying 'spatial current' (?) , created by local differences in the ZPF.
+2cts -
#3146 by rfmwguy on 25 Feb, 2016 17:16
-
I've invited Mr McCullough to join the forum and address questions...
-
#3147 by Rodal on 25 Feb, 2016 17:24
-
I've invited Mr McCullough to join the forum and address questions...
Dr. McCullough is already a member of the NSF forum and has previously posted in previous EM Drive threads -
#3148 by rfmwguy on 25 Feb, 2016 17:25
-
Username?I've invited Mr McCullough to join the forum and address questions...
Dr. McCullough is already a member of the NSF forum and has previously posted in previous EM Drive threads -
#3149 by SeeShells on 25 Feb, 2016 17:33
-
You'll see the differences in endplate lengths is the contributing factor to the changes in resonance. The flat vs the curved in mode standing wave generation is mainly you get a little more quality of mode shape for a curved.
How different a frequency for resonance with flat plates vs spherical ends ?
For what spherical radii? for what cone half-angles?
I would have to run another frequency sweep on the flat end frustum to know how different the frequency for resonance is. That will take a couple of hours.
This is what I have for dimensions:
Large end Spherical radius: 30 cm
Large end diameter (same as flat end frustum): 22.96 cm
Side wall length (same as flat end frustum): 18.3569 cm
NOTE: This is different than flat-end frustum total height, which is: 16.968 cm
Small end Spherical radius: 11.634 cm
Small end diameter (same as flat end frustum): 8.904 cm
There is probably a sweet spot in spherical radius. I can be on one end of that, but I think I am testing a moderate curve - nothing too extreme.
Shell -
#3150 by SeeShells on 25 Feb, 2016 17:43
-
I like to think of the ZPF as a GND or reference plane, like in electronics. Perhaps the idea is something as a ground loop carrying 'spatial current' (?) , created by local differences in the ZPF.
+2cts
Grounds in electronics are highly over rated as there is no real ground but a difference in potentials. I've run TTL in high potential grounded systems of several hundred volts and it's called a floating ground. You also have differences in grounds in AC systems where the phasing of the return paths changes in potentials along its length.
What we may have here in the Drive is a closed floating high energy system where "effects" are somewhat isolated from the QV of spacetime. Although I don't want to go there as I become a Engineer playing in physics.
Shell -
#3151 by Rodal on 25 Feb, 2016 17:58
-
You'll see the differences in endplate lengths is the contributing factor to the changes in resonance. The flat vs the curved in mode standing wave generation is mainly you get a little more quality of mode shape for a curved.
How different a frequency for resonance with flat plates vs spherical ends ?
For what spherical radii? for what cone half-angles?
I would have to run another frequency sweep on the flat end frustum to know how different the frequency for resonance is. That will take a couple of hours.
This is what I have for dimensions:
Large end Spherical radius: 30 cm
Large end diameter (same as flat end frustum): 22.96 cm
Side wall length (same as flat end frustum): 18.3569 cm
NOTE: This is different than flat-end frustum total height, which is: 16.968 cm
Small end Spherical radius: 11.634 cm
Small end diameter (same as flat end frustum): 8.904 cm
There is probably a sweet spot in spherical radius. I can be on one end of that, but I think I am testing a moderate curve - nothing too extreme.
Shell
Thanks for noticing that Shell !
Yes, the effect of curved ends vs flat ends is really negligible for typical EM Drive geometries as opposed to the length of the frustum, which of course has a much greater effect. -
#3152 by Monomorphic on 25 Feb, 2016 18:10
-
Yes, the effect of curved ends vs flat ends is really negligible for typical EM Drive geometries as opposed to the length of the frustum, which of course has a much greater effect.
The curved ends can add a centimeter or more to the length depending on spherical radius. The two I am testing have a difference in length of 1.3889 cm, despite identical side wall length, end plate radii, and half-cone angle. Considering 2.7Ghz has a wavelength of around 11 cm - that difference seems significant. I'm about half-way through the frequency sweep on the flat-end frustum now. Should have some answers shortly. -
#3153 by SeeShells on 25 Feb, 2016 18:15
-
It gets real interesting when you do a 6 sided curved endplate like I was doing at the start of the testing with perforated walls.
You'll see the differences in endplate lengths is the contributing factor to the changes in resonance. The flat vs the curved in mode standing wave generation is mainly you get a little more quality of mode shape for a curved.
How different a frequency for resonance with flat plates vs spherical ends ?
For what spherical radii? for what cone half-angles?
I would have to run another frequency sweep on the flat end frustum to know how different the frequency for resonance is. That will take a couple of hours.
This is what I have for dimensions:
Large end Spherical radius: 30 cm
Large end diameter (same as flat end frustum): 22.96 cm
Side wall length (same as flat end frustum): 18.3569 cm
NOTE: This is different than flat-end frustum total height, which is: 16.968 cm
Small end Spherical radius: 11.634 cm
Small end diameter (same as flat end frustum): 8.904 cm
There is probably a sweet spot in spherical radius. I can be on one end of that, but I think I am testing a moderate curve - nothing too extreme.
Shell
Thanks for noticing that Shell !
Yes, the effect of curved ends vs flat ends is really negligible for typical EM Drive geometries as opposed to the length of the frustum, which of course has a much greater effect.
I suspect that the surface area of the curved shape in a cone frustum has a little bearing on frequency but it can't be much.
Shell -
#3154 by Rodal on 25 Feb, 2016 18:19
-
You are correct. When I have the time I will publish a formal proof vs comparison with COMSOL in the other thread
It gets real interesting when you do a 6 sided curved endplate like I was doing at the start of the testing with perforated walls.
You'll see the differences in endplate lengths is the contributing factor to the changes in resonance. The flat vs the curved in mode standing wave generation is mainly you get a little more quality of mode shape for a curved.
How different a frequency for resonance with flat plates vs spherical ends ?
For what spherical radii? for what cone half-angles?
I would have to run another frequency sweep on the flat end frustum to know how different the frequency for resonance is. That will take a couple of hours.
This is what I have for dimensions:
Large end Spherical radius: 30 cm
Large end diameter (same as flat end frustum): 22.96 cm
Side wall length (same as flat end frustum): 18.3569 cm
NOTE: This is different than flat-end frustum total height, which is: 16.968 cm
Small end Spherical radius: 11.634 cm
Small end diameter (same as flat end frustum): 8.904 cm
There is probably a sweet spot in spherical radius. I can be on one end of that, but I think I am testing a moderate curve - nothing too extreme.
Shell
Thanks for noticing that Shell !
Yes, the effect of curved ends vs flat ends is really negligible for typical EM Drive geometries as opposed to the length of the frustum, which of course has a much greater effect.
I suspect that the surface area of the curved shape in a cone frustum has a little bearing on frequency but it can't be much.
Shell
-
#3155 by Monomorphic on 25 Feb, 2016 18:34
-
When I have the time I will publish a formal proof vs comparison with COMSOL in the other thread
My suspicion is we will find that the smaller the spherical radii, the greater the divergence in resonant frequency vs an otherwise identical flat-end frustum. Shawyer uses a pretty small radius in his superconducting model.
-
#3156 by Monomorphic on 25 Feb, 2016 19:32
-
Frequency sweep finished on flat-end frustum. I'm showing strongest TE013 resonance at 2.88889Ghz, vs the 2.73737 for the spherical end-plate frustum. This is a difference of 151.52Mhz. In addition, full power at resonance was only 1/4 that of the spherical end-plate frustum (7,500 kV/m vs 1,750 kV/m).
I need to run frequency sweeps over 300Mhz centered on 2.88889 and 2.73737Ghz as stronger resonance could have been missed since there is a limited number of frequency steps. So these numbers may move around. We'll see how much of that 151Mhz I can make up, but I can't imagine it being that much.
-
#3157 by X_RaY on 25 Feb, 2016 19:50
-
Frequency sweep finished on flat-end frustum. I'm showing TE013 resonance at 2.88889Ghz, vs the 2.73737 for the spherical end-plate frustum. This is a difference of 151.52Mhz. In addition, full power at resonance was only 1/4 that of the spherical end-plate frustum (7,500 kV/m vs 1,750 kV/m).
Nice results!
I need to run frequency sweeps over 300Mhz centered on 2.88889 and 2.73737Ghz as stronger resonance could have been missed since there is a limited number of frequency steps. So these numbers may move around. We'll see how much of that 151Mhz I can make up, but I can't imagine it being that much. Could you so kind to add the power/frequency graphs or even magnitude/frequency and/or the complex S parameter for your last simulations?
(I know it depends on the port/source definition and used requests ) -
#3158 by Rodal on 25 Feb, 2016 19:56
-
Frequency sweep finished on flat-end frustum. I'm showing TE013 resonance at 2.88889Ghz, vs the 2.73737 for the spherical end-plate frustum. This is a difference of 151.52Mhz. In addition, full power at resonance was only 1/4 that of the spherical end-plate frustum (7,500 kV/m vs 1,750 kV/m).
OK that is a difference of only 5.5 % in resonant frequency between spherical ends and flat ends.
I need to run frequency sweeps over 300Mhz centered on 2.88889 and 2.73737Ghz as stronger resonance could have been missed since there is a limited number of frequency steps. So these numbers may move around. We'll see how much of that 151Mhz I can make up, but I can't imagine it being that much.
This is what I expected (only a few % difference in resonant frequency), and it is very much in line with my previous calculations.
What is the geometrical tolerance of the frustum of a cones made so far? Early on TheTraveller was pointing out differences of ~5% as signficant in his opinion, but when it came to make his own experimental frustum of a cone he has reported that imperfections due to home-construction are such that they detract from the Q, and he is exploring manufacturing alternatives to improve the geometrical tolerance.
This has also been pointed out by the Chinese co-worker of Prof. Yang that briefly visited the NSF forum a few weeks ago: geometrical imperfections are easily going to impact the natural frequency and most importantly going to affect the Q.
-
#3159 by Rodal on 25 Feb, 2016 20:04
-
Usually it is not a good idea to disclose username identities, and of course I'm not going to do this. Dr. McCulloch has not been using a monicker, and it easy to find his posts using Google search, for example:
Username?I've invited Mr McCullough to join the forum and address questions...
Dr. McCullough is already a member of the NSF forum and has previously posted in previous EM Drive threads
http://forum.nasaspaceflight.com/index.php?topic=36313.msg1336056#msg1336056QuoteDear excellent NSF forum. This is just to say (for those who don't know) that I've suggested a specific new model for inertia that predicts galaxy rotation without dark matter (it is called MiHsC) and I recently compared its predictions with the 9 EmDrive results with 'some' (not perfect) success. You can see the results by looking at the Table here:
http://physicsfromtheedge.blogspot.co.uk/2015/02/mihsc-vs-emdrive-data-3d.html
I've also published a paper summarising this comparison (slightly out of date now) here
http://www.ptep-online.com/index_files/2015/PP-40-15.PDF
I'd encourage those with other interesting explanations of the EmDrive to make a similar comparison between predictions and data, so we can compare using the facts. If you have any more data points to add, or if you disagree with the numbers in my Table, please let me know.
NSF member section shows that he is still a member of NSF.
