Another article from Ethan Seigal on the Forbes website:
http://www.forbes.com/sites/startswithabang/2016/11/30/could-dark-matter-be-powering-the-emdrive/#25e019901e53
Interesting conjecture that instead of pushing against the QV (which Woodward tells us the EMDrive can't do), the drive is instead expelling dark matter like a normal rocket through photon-axion interaction.
"How would it work? At any point in time, there are dark matter particles passing through all regions of space, undeterred by the presence of matter or other Standard Model particles. Inside the electromagnetic cavity, photons of a particular frequency bounce around in all directions, conserving momentum and generating no thrust. But if photons moving in a particular direction — towards the ‘back’ of the cavity, for example — are likely to strike a dark matter particle, three things ensue:
1) The photon changes momentum, and moves “less backwards” and “more forwards” than before it struck the dark matter particle.
2) The photon strikes the inside wall of the cavity, reflecting off of it and imparting its momentum in the forward direction to the cavity itself.
3) The struck dark matter particle gains momentum as well in the opposite direction: backwards.
Momentum is conserved because the dark matter carries it away, equal and opposite in magnitude to what the cavity absorbs."
For those considering building a YBCO based frustum, as I am, here are 2 interesting graphs:
1st is 2015 data showing max H field vs temp vs various superconductors. From this data it would seem that YBCO is the champ material for dealing with high H field, which suggests it can handle very high Q frustum builds.
2nd is 2009 data from Roger Shawyer showing YBCO Rs vs various temperatures at 3.85GHz. Note that the ~78uOhm value in 2009 is now 3uOhm in 2016.
While LNe is somewhat expensive, it does appear to offer a 5x lower Rs (5x higher Q) and 2.5x higher max Hc so maybe worth giving it a shot?
For sure design for LN2 and if you need to go further maybe consider LNe instead of LH2 or LHe?YBCO is a ceramic compound. The gap to excitations that leads to superconductivity is a result of pairs of electrons (or other fermions) bound together at (very) low temperatures, and thats in the case of ceramic superconductors usualy a surface effect. If a magnetic field is close to these type of superconductors the effect will be lost. (meissner ochsenfeld effect) as the frustrum works with a crude coil as rf transmitter , so how does Shawyer prevent magnetic interference and loss of superconductivity?
For those considering building a YBCO based frustum, as I am, here are 2 interesting graphs:
1st is 2015 data showing max H field vs temp vs various superconductors. From this data it would seem that YBCO is the champ material for dealing with high H field, which suggests it can handle very high Q frustum builds.
2nd is 2009 data from Roger Shawyer showing YBCO Rs vs various temperatures at 3.85GHz. Note that the ~78uOhm value in 2009 is now 3uOhm in 2016.
While LNe is somewhat expensive, it does appear to offer a 5x lower Rs (5x higher Q) and 2.5x higher max Hc so maybe worth giving it a shot?
For sure design for LN2 and if you need to go further maybe consider LNe instead of LH2 or LHe?YBCO is a ceramic compound. The gap to excitations that leads to superconductivity is a result of pairs of electrons (or other fermions) bound together at (very) low temperatures, and thats in the case of ceramic superconductors usualy a surface effect. If a magnetic field is close to these type of superconductors the effect will be lost. (meissner ochsenfeld effect) as the frustrum works with a crude coil as rf transmitter , so how does Shawyer prevent magnetic interference and loss of superconductivity?
Very good question(s). From what I have read in these discussions and the limited information available from a few of Shawyer's papers/patent, upscalling the frustum to a superconducting cryogenic design is based on an assumption that high Q is the dominant factor in developing high thrust. Without any published experimental data involving a superconducting EmDrive design, it appears to me to be a theoretical leap of faith.
So the short answer is there seems to be a race by some to try and be the first, which demands an almost blind faith in conclusions based on flawed or incomplete theoretical interpretations of .....
I do tend to run on and often present off the wall observations and interpretations of my own, so in the spirit of old maps, "be warned beyond here there be dragons!"
As a non-expert in any of the areas specific to the design and construction of a functional device, and based only on what understanding I have been able to tease out of these discussions, it would seem far more productive to refine a room temperature design which if which of what information that has been made available should be able to developed thrusts in the Newton/Kw range, before chasing what seems purely theoretical upscalling based on what at present is very limited published data from mostly 1st to perhaps 3rd generation engineering attempts to recreate poorly described devices claiming up to triple digit mN/Kw results.
Any device that could consistently produce triple digit mN/Kw thrusts at room temperatures, would provide a far better basis for exploring any functionally measurable design and/or materials based aspects contributing to those results.
Right now from a peanut gallery observer, without better design blueprints from previously successful experiments, chasing superconducting promises of multi ton thrusts, just seems foolish.
The EW paper seems to have provided the first reliable data demonstrating repeatable thrust, but unless I am mistaken the frustum design and TM mode, in those tests, do not represent the only or perhaps even best approach, for obtaining higher room temperature thrusts.
Also I believe in Shawyer's last partnership patent, only the large flat end plate was coated with a superconducting material.
See the attached for clarification. Note the force direction arrows in the bottom images that point to the end plate with the shortest 1/2 wave, that has the highest photon momentum & radiation pressure.
TT, you're showing data for Eagleworks' frustum with dielectric at small end and TE012 mode, where max E & H fields are located near small end.
Whereas zellerium, WarpTech and Star-Drive are discussing Eagleworks' frustum with dielectric at small end and TM212 mode, where max E & H fields are located near big end. Besides, in that particular mode only 10% of the RF energy resides in the PE discs.
Your "shorter vs longer 1/2 wave" conjecture may still apply, but the two field configurations are very different, and their max strength values are located opposite from each other.
We only have data for TE012 for both dielectric and non dielectric forces and direction.
It is which end has the shortest 1/2 that is of interest as the shortest 1/2 wave has the highest momentum and radiation pressure.
As Roger has shown, without dielectrics, as attached, the static force is generated small to big as Paul and I also measured and observed.
Any theory needs to be able to explain the force direction and why it swaps direction with and without dielectric when excited in the same mode.
I may be that where the highest energy density is located is not what is creating the measured static force with a direction big to small when a dielectric is at the small end.
Please note the measured force direction, big to small is the same for ALL the EW tests and seems to be mode independent.
The EW mode map I have seen has shown the TM212 dielectric frustum also has the shortest 1/2 wave at the small end, which is consistent with the measured force direction being big to small.
Zellerium's mode map in TM212 also shows the shortest 1/2 wave at the small end, which us consistent with the EW TM212 mode map.
TT,
For the NASA TE012 mode data, my theory did predict the reversed direction of force when the dielectric was added. However, the TM212 mode simulation that @zellerium just posted shows a different configuration of energy, wavelength and losses. IMO, the only issue is that I went by what was shown on the graphs as "Volume Loss Density", when I believe we should be looking at "Surface Loss Density", to have an accurate representation. Then it would be obvious that in the TM212 mode the majority of losses are at the big end, when the dielectric is present "shielding" the small end from those surface losses.
According to radiation pressure theory, the big to small accelerative force is the equal but opposite Reaction force to the small to big static Thrust force.
For those considering building a YBCO based frustum, as I am, here are 2 interesting graphs:
1st is 2015 data showing max H field vs temp vs various superconductors. From this data it would seem that YBCO is the champ material for dealing with high H field, which suggests it can handle very high Q frustum builds.
2nd is 2009 data from Roger Shawyer showing YBCO Rs vs various temperatures at 3.85GHz. Note that the ~78uOhm value in 2009 is now 3uOhm in 2016.
While LNe is somewhat expensive, it does appear to offer a 5x lower Rs (5x higher Q) and 2.5x higher max Hc so maybe worth giving it a shot?
For sure design for LN2 and if you need to go further maybe consider LNe instead of LH2 or LHe?YBCO is a ceramic compound. The gap to excitations that leads to superconductivity is a result of pairs of electrons (or other fermions) bound together at (very) low temperatures, and thats in the case of ceramic superconductors usualy a surface effect. If a magnetic field is close to these type of superconductors the effect will be lost. (meissner ochsenfeld effect) as the frustrum works with a crude coil as rf transmitter , so how does Shawyer prevent magnetic interference and loss of superconductivity?
Very good question(s). From what I have read in these discussions and the limited information available from a few of Shawyer's papers/patent, upscalling the frustum to a superconducting cryogenic design is based on an assumption that high Q is the dominant factor in developing high thrust. Without any published experimental data involving a superconducting EmDrive design, it appears to me to be a theoretical leap of faith.
So the short answer is there seems to be a race by some to try and be the first, which demands an almost blind faith in conclusions based on flawed or incomplete theoretical interpretations of .....
I do tend to run on and often present off the wall observations and interpretations of my own, so in the spirit of old maps, "be warned beyond here there be dragons!"
As a non-expert in any of the areas specific to the design and construction of a functional device, and based only on what understanding I have been able to tease out of these discussions, it would seem far more productive to refine a room temperature design which if which of what information that has been made available should be able to developed thrusts in the Newton/Kw range, before chasing what seems purely theoretical upscalling based on what at present is very limited published data from mostly 1st to perhaps 3rd generation engineering attempts to recreate poorly described devices claiming up to triple digit mN/Kw results.
Any device that could consistently produce triple digit mN/Kw thrusts at room temperatures, would provide a far better basis for exploring any functionally measurable design and/or materials based aspects contributing to those results.
Right now from a peanut gallery observer, without better design blueprints from previously successful experiments, chasing superconducting promises of multi ton thrusts, just seems foolish.
The EW paper seems to have provided the first reliable data demonstrating repeatable thrust, but unless I am mistaken the frustum design and TM mode, in those tests, do not represent the only or perhaps even best approach, for obtaining higher room temperature thrusts.
Also I believe in Shawyer's last partnership patent, only the large flat end plate was coated with a superconducting material.
YBCO seems to have the highest Hc of any superconductor as I posted shortly ago.
The 60T indicated at LN2 temp is ~4.77x10^7 A/m.
As cavity TE013 H fields are max in the centre of the cavity, the side wall and end plate H fields are very low.
Please check back a few posts for the images.
Spherical cavity E * H fields:
http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=41732.0;attach=1391125;image
YBCO Hc field sensitivity vs temp:
http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=41732.0;attach=1391109;image
According to radiation pressure theory, the big to small accelerative force is the equal but opposite Reaction force to the small to big static Thrust force.This is not "according to radiation pressure theory." This is from statements by Shawyer in a paper where he utterly fails at a Physics 101 force diagram.
I have asked you many, many times to answer simple questions about a simple mechanical setup (originally in this post), which you have refused to do. These questions are important to clarify the definitions of terms that you are using. You are confusing everyone because you are using the word force in a way that contradicts the definition of a force.
I ask again since this is the beginning of a new thread, and it would be nice to have some rational discourse.
According to radiation pressure theory, the big to small accelerative force is the equal but opposite Reaction force to the small to big static Thrust force.This is not "according to radiation pressure theory." This is from statements by Shawyer in a paper where he utterly fails at a Physics 101 force diagram.
I have asked you many, many times to answer simple questions about a simple mechanical setup (originally in this post), which you have refused to do. These questions are important to clarify the definitions of terms that you are using. You are confusing everyone because you are using the word force in a way that contradicts the definition of a force.
I ask again since this is the beginning of a new thread, and it would be nice to have some rational discourse.
I thought you'd know by now how TT will answer. The route this conversation takes goes as follows:
1) Statement that the theoretical explanations on offer are non-nonsensical
2) Contradictions are rebuffed by endorsing data above theory
3) Statements to the effect that all theories are flawed but the good ones still make physical sense
4) Appeal to the authority of Shawyer because he made EM Drive work
5) Go to 1
According to radiation pressure theory, the big to small accelerative force is the equal but opposite Reaction force to the small to big static Thrust force.This is not "according to radiation pressure theory." This is from statements by Shawyer in a paper where he utterly fails at a Physics 101 force diagram.
I have asked you many, many times to answer simple questions about a simple mechanical setup (originally in this post), which you have refused to do. These questions are important to clarify the definitions of terms that you are using. You are confusing everyone because you are using the word force in a way that contradicts the definition of a force.
I ask again since this is the beginning of a new thread, and it would be nice to have some rational discourse.
Static force: Causes a scale or torsion pendulum to record a force acting against or with the scale or torsion pendulum. Equation F = (2 Qu Pwr Df) / c.
Dynamic force: Causes the free to accelerate acceleration of mass and is measured via F = A * M.
Can't measure both forces at the same time.
According to radiation pressure theory, the big to small accelerative force is the equal but opposite Reaction force to the small to big static Thrust force.This is not "according to radiation pressure theory." This is from statements by Shawyer in a paper where he utterly fails at a Physics 101 force diagram.
I have asked you many, many times to answer simple questions about a simple mechanical setup (originally in this post), which you have refused to do. These questions are important to clarify the definitions of terms that you are using. You are confusing everyone because you are using the word force in a way that contradicts the definition of a force.
I ask again since this is the beginning of a new thread, and it would be nice to have some rational discourse.
Static force: Causes a scale or torsion pendulum to record a force acting against or with the scale or torsion pendulum. Equation F = (2 Qu Pwr Df) / c.
Dynamic force: Causes the free to accelerate acceleration of mass and is measured via F = A * M.
Can't measure both forces at the same time.That is not an answer to the questions I asked. That is just providing the same contradictory definitions, because no force measurement is static, they all start with an acceleration, and the torsion pendulum and scale measure how much force is required to hold back the acceleration. The only way I know how to explain this more clearly is by example, but you refuse to actually work through the example with me.
As I said in reply to RotoSequence:
I am tired of this cycle but figured I would give it one last shot. Just know that in the future when no one counters your claims it is only because everyone has given up on you listening to reason.
I would like my simple question to be answered too:
What is causing the 1/2 wave to lengthen on one side and shorten on the other side, but a local variation of the wavelength?
You are missing the point that this is all a theoretical leap of faith, that assumes there is nothing other than Q that affects the resultant thrust. The EM field being introduced into the frustum interacts with the materials of the frustum walls in more ways than just the Q achieved by design and frequency match. There are other differences between copper and YBCO than just Q
I would like my simple question to be answered too:
What is causing the 1/2 wave to lengthen on one side and shorten on the other side, but a local variation of the wavelength?
Another article from Ethan Seigal on the Forbes website:
http://www.forbes.com/sites/startswithabang/2016/11/30/could-dark-matter-be-powering-the-emdrive/#25e019901e53
Interesting conjecture that instead of pushing against the QV (which Woodward tells us the EMDrive can't do), the drive is instead expelling dark matter like a normal rocket through photon-axion interaction.
"How would it work? At any point in time, there are dark matter particles passing through all regions of space, undeterred by the presence of matter or other Standard Model particles. Inside the electromagnetic cavity, photons of a particular frequency bounce around in all directions, conserving momentum and generating no thrust. But if photons moving in a particular direction — towards the ‘back’ of the cavity, for example — are likely to strike a dark matter particle, three things ensue:
1) The photon changes momentum, and moves “less backwards” and “more forwards” than before it struck the dark matter particle.
2) The photon strikes the inside wall of the cavity, reflecting off of it and imparting its momentum in the forward direction to the cavity itself.
3) The struck dark matter particle gains momentum as well in the opposite direction: backwards.
Momentum is conserved because the dark matter carries it away, equal and opposite in magnitude to what the cavity absorbs."
I think it is much more likely and practical, that momentum is carried into the copper and through it by magnetic flux, which pass through due to the voltage drop (losses) from resistance and current.
According to radiation pressure theory, the big to small accelerative force is the equal but opposite Reaction force to the small to big static Thrust force.This is not "according to radiation pressure theory." This is from statements by Shawyer in a paper where he utterly fails at a Physics 101 force diagram.
I have asked you many, many times to answer simple questions about a simple mechanical setup (originally in this post), which you have refused to do. These questions are important to clarify the definitions of terms that you are using. You are confusing everyone because you are using the word force in a way that contradicts the definition of a force.
I ask again since this is the beginning of a new thread, and it would be nice to have some rational discourse.
I thought you'd know by now how TT will answer. The route this conversation takes goes as follows:
1) Statement that the theoretical explanations on offer are non-nonsensical
2) Contradictions are rebuffed by endorsing data above theory
3) Statements to the effect that all theories are flawed but the good ones still make physical sense
4) Appeal to the authority of Shawyer because he made EM Drive work
5) Go to 1I know, I am just giving it one last shot in light of the new thread (and for casual readers who look through the first few pages of a thread), my response to #2 this time (unless TT changes his pattern, and actually answers my questions) is planned to be along the lines of "I am tired of this cycle but figured I would give it one last shot. Just know that in the future when no one counters your claims it is only because everyone has given up on you listening to reason."
According to radiation pressure theory, the big to small accelerative force is the equal but opposite Reaction force to the small to big static Thrust force.This is not "according to radiation pressure theory." This is from statements by Shawyer in a paper where he utterly fails at a Physics 101 force diagram.
I have asked you many, many times to answer simple questions about a simple mechanical setup (originally in this post), which you have refused to do. These questions are important to clarify the definitions of terms that you are using. You are confusing everyone because you are using the word force in a way that contradicts the definition of a force.
I ask again since this is the beginning of a new thread, and it would be nice to have some rational discourse.
FYI: