...Quote from: Paul Novy on 05/28/2015 07:49 am..."Macroscopic and Direct Light Propulsion of Bulk Graphene Material"http://arxiv.org/ftp/arxiv/papers/1505/1505.04254.pdfMy question here is what do the CoM (conservation of mass) and CoE (conservation of energy) people think about this force on the graphene? Obviously it is much larger than that of just light. Do we still have a violation here? What is interesting is it is being observed in matter. Whats to stop them from using a mirror behind a ship and reflecting the laser to propel the ship? It might not be the right thing to do but we could even shove a graphene sponge in the narrow end of the cavity and let that magnetron go. Well I diverge but my question is regarding the CoM and CoE argument.
..."Macroscopic and Direct Light Propulsion of Bulk Graphene Material"http://arxiv.org/ftp/arxiv/papers/1505/1505.04254.pdf
Returning to Randall/Sundrum for a moment. It’s been pointed out over and over again that the EMDrive, as it is proposed to operate, violates CoM - no disagreement there. ...
Quote from: WarpTech on 05/29/2015 01:46 pmQuote from: Rodal on 05/29/2015 12:29 pm...When you state: <<Optimize their integral force equation for the correct representation for D, E and B, H, i.e., NOT standing waves>> are you proposing to only consider the evanescent wave terms and to ignore the standing wave terms in the analysis? (since the standing wave terms perfectly cancel out when averaged over an integer number of time periods)Or do you see any interaction/coupling between the standing wave terms and the evanescent wave terms so that both have to be considered in the analysis?....The interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.Minor point, but the standing waves lose energy to the electrons in the copper, which in turn, radiate at SHORTER wavelengths. IR has shorter wavelengths than microwave.
Quote from: Rodal on 05/29/2015 12:29 pm...When you state: <<Optimize their integral force equation for the correct representation for D, E and B, H, i.e., NOT standing waves>> are you proposing to only consider the evanescent wave terms and to ignore the standing wave terms in the analysis? (since the standing wave terms perfectly cancel out when averaged over an integer number of time periods)Or do you see any interaction/coupling between the standing wave terms and the evanescent wave terms so that both have to be considered in the analysis?....The interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.
...When you state: <<Optimize their integral force equation for the correct representation for D, E and B, H, i.e., NOT standing waves>> are you proposing to only consider the evanescent wave terms and to ignore the standing wave terms in the analysis? (since the standing wave terms perfectly cancel out when averaged over an integer number of time periods)Or do you see any interaction/coupling between the standing wave terms and the evanescent wave terms so that both have to be considered in the analysis?....
Quote from: WarpTech on 05/29/2015 01:46 pmThe interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.Todd, although I understood the general lines of the mechanism you're describing, I'm a bit confused about the frequency shifting. Initially you said that the shape of the cavity was the reason for the attenuation of the waves, where now you seem to put the wavelength shift to thermal causes?Furthermore, doesn't the heat have a negative impact on the Q ? with a higher Q, you can store more energy in the standing waves, but more energy means more heat... At some point they must equalize eachother, no? That would also mean that Shawyer's projections of having Q's running into the millions will probably never materialize?Unless there are other ways to achieve attenuation without the thermo effects?
The interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.
Would be nice if Aero could modify his model to include copper loss in the waveguide. I'm still looking at old thread 2 posts. It would also be nice if Aero could post his .ctl file. Thanks.
Quote from: phaseshift on 05/29/2015 05:08 pmReturning to Randall/Sundrum for a moment. It’s been pointed out over and over again that the EMDrive, as it is proposed to operate, violates CoM - no disagreement there. ...Sorry, but to clarify, yes there is disagreement. There are lots of explanations for the EM Drive and I don't know of any author that has proposed EM Drive thrust while simultaneously claiming violation of Conservation of Momentum.
Quote from: Flyby on 05/29/2015 04:12 pmQuote from: WarpTech on 05/29/2015 01:46 pmThe interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.Todd, although I understood the general lines of the mechanism you're describing, I'm a bit confused about the frequency shifting. Initially you said that the shape of the cavity was the reason for the attenuation of the waves, where now you seem to put the wavelength shift to thermal causes?Furthermore, doesn't the heat have a negative impact on the Q ? with a higher Q, you can store more energy in the standing waves, but more energy means more heat... At some point they must equalize eachother, no? That would also mean that Shawyer's projections of having Q's running into the millions will probably never materialize?Unless there are other ways to achieve attenuation without the thermo effects?I believe that if the frustum were perfectly conductive, with no thermal losses at all, there would be no thrust. The reason being, the lowest frequency injected is still above the cut-off of the small end. So the attenuation would be minimal, but when there is thermal dissipation there is scattering of the microwaves that cause them to lose energy and shift to lower frequency and stretch to longer wavelengths that are strongly attenuated toward the front. Higher Q means more available energy in this bandwidth of evanescent waves.As I said, I am learning. I don't have all the answers and I tend to think out-loud. These discussions help me a lot but please take them with a grain of salt, until I publish a paper! Thanks!
Quote from: dustinthewind on 05/29/2015 07:25 am...Quote from: Paul Novy on 05/28/2015 07:49 am..."Macroscopic and Direct Light Propulsion of Bulk Graphene Material"http://arxiv.org/ftp/arxiv/papers/1505/1505.04254.pdfMy question here is what do the CoM (conservation of mass) and CoE (conservation of energy) people think about this force on the graphene? Obviously it is much larger than that of just light. Do we still have a violation here? What is interesting is it is being observed in matter. Whats to stop them from using a mirror behind a ship and reflecting the laser to propel the ship? It might not be the right thing to do but we could even shove a graphene sponge in the narrow end of the cavity and let that magnetron go. Well I diverge but my question is regarding the CoM and CoE argument. I read this, nice research, nice find, still struggling to understand how the sample, when levitated, can neutralize the charge build-up that would occur though. There is no CoM or CoE argument against this find, this is no fundamentally different from a beamed ablative propulsion scheme. The injected energy is used to expel particles of mass>0, therefore it is to be expected that the thrust/power ratio is 1/ Bigger than that of a photon rocket if power counts only the imparted energy2/ Lower than that of a photon rocket if power counts imparted energy + mass equivalent energy of expelled particlesThis is not propellantless, the floated device loses mass. The exotic aspect is that the expelled mass is electrons, but this is sooner or later (rather sooner) to be paid back as the devices builds up charge and it gets more and more difficult to release electrons against this growing voltage. For continuous operation it has to be replenished in electrons. Recycling the ejected electrons would cancel any net thrust, like a traditional rocket that would try to swallow back its exhaust. So this needs a source of "free" electrons, if possible harvested at low velocity relative to system. This is not unlike a jet engine that needs to swallow ambient mass and uses power to accelerate it and expel it faster backward, everything is ok as far as CoM and CoE is concerned, that can't be used as an apparent free energy generator, unlike an EM drive thrusting continuously (constant thrust for constant power) at constant velocity (no acceleration) above a certain velocity.
Returning to Randall/Sundrum for a moment. It’s been pointed out over and over again that the EMDrive, as it is proposed to operate, violates CoM - no disagreement by me there. IF it does actually produce thrust then the answer must be 'outside the box’ (pun intended). In the interview video, that was posted several days ago with Randall and Sundrum, Sundrum briefly talks about how CoM can be violated (in appearance). Their theory, which has nothing to do with the EM drive, says that there is another 3 dimensional space called the Planck brane, sometimes it’s called the Gravity brane, or Strong brane, exists in parallel to our 3-space brane (the Tev brane) and they are joined by a finite dimension that is very short. The distance between the Gravity brane and our Tev brane is the reason that gravity is such a comparatively weak force. Sundrum says in the interview that energy, and mass, could move into this dimension (or possibly other dimensions), where we can not directly measure it and thus energy/momentum seems to disappear. By-the-way the Randall-Sundrum Model is the first theory to come from string theory that is testable and will be tested at CERN this summer (2015); it's being taken very seriously. IF they are right - what does the energy/mass do when it moves into this finite dimension? Remember at the end of this dimension is the Planck brane. The dimension is very much like a cavity. Two things come to my mind:1. Is it possible that the ‘thrust’ is pushing off the internals of this dimension? Sound familiar? I think this is close to what Dr. White is suggesting - though he says ‘Quantum Vacuum’. By internals I mean whatever resides in the dimension - who knows what that could be.2. Our Universe may have begun with an inflationary period where all the dimensions grew at rates far beyond the speed of light. Why didn’t this 4th dimension inflate as well? What is keeping it the size that it is? Can its size be changed? (the other dimensions changed size, and still are). If Randall/Sundrum are correct than any change in size of this 4th dimension will change the local gravitational force. Is there something about the specific frequencies and shape of the EM drive frustum that allow some very small amount of energy to enter this 4th dimension? Can this energy change the size of the dimension and thus the strength of gravity? What would be the magnitude of the change in gravity if the dimension increased by 10%, or doubled? Dr. White is using an interferometer to measure changes in the shape of space-time within the frustum by aiming a laser through a window on each side. While the results are super borderline above noise it might show a blue shifting of the laser which would indicate a lower gravitational force - a red shift would indicate a larger gravitational force. If the 4th dimension were to increase in length gravity would be weaker, space would not be as curved, and there would be a blue shift in the laser.One might argue that we should have seen the affects of this before now. Maybe we have, but the affects are so small, that they have gone unnoticed, or we have assigned them a ‘constant’ - just like we have recently done with the cosmological constant - just to make the equations produce the right results.
...Agreed. If the EMDrive does work, it violates CoM in our 4D-spacetime but not necessarily in a hypothetical {branes + bulk} 5D-spacetime.
Quote from: Notsosureofit on 05/29/2015 04:01 pmQuote from: WarpTech on 05/29/2015 01:46 pmQuote from: Rodal on 05/29/2015 12:29 pm...When you state: <<Optimize their integral force equation for the correct representation for D, E and B, H, i.e., NOT standing waves>> are you proposing to only consider the evanescent wave terms and to ignore the standing wave terms in the analysis? (since the standing wave terms perfectly cancel out when averaged over an integer number of time periods)Or do you see any interaction/coupling between the standing wave terms and the evanescent wave terms so that both have to be considered in the analysis?....The interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.Minor point, but the standing waves lose energy to the electrons in the copper, which in turn, radiate at SHORTER wavelengths. IR has shorter wavelengths than microwave.True for the IR, but scattering of microwave photons by the metal will down-grade them to lower energy, longer wavelengths, which can then be attenuated.
"Macroscopic and Direct Light Propulsion of Bulk Graphene Material"http://arxiv.org/ftp/arxiv/papers/1505/1505.04254.pdf
Quote from: WarpTech on 05/28/2015 07:38 pmQuote from: Paul Novy on 05/28/2015 07:49 amI'm just gonna leave this here..."Macroscopic and Direct Light Propulsion of Bulk Graphene Material"http://arxiv.org/ftp/arxiv/papers/1505/1505.04254.pdfQuoteThe force generated from such a process/mechanism is muchlarger than the force generated directly from the conventional light pressure, which ismuch smaller than the force required to propel the samples. QuoteThe mechanism behind this novel phenomenon is believed to be anefficient light-induced ejected electron emission process, following an Auger-like pathdue to both the unique band structure of graphene and its macroscopic morphology ofthis unique material. This article is showing that for certain types of materials, light can impart more force to the material, than it would if it were simply used to as a photon rocket to push the same material. The difference is the Auger Effect, where the incoming light causes a population inversion in the material, that then causes electrons to be ejected from the material, greatly increasing the force by many orders of magnitude. Perhaps a similar effect can be obtained asymmetrically in a cavity?Thank you for posting it!ToddMy question here is what do the CoM (conservation of Edit:momentum) and CoE (conservation of energy) people think about this force on the graphene? Obviously it is much larger than that of just light. Do we still have a violation here? What is interesting is it is being observed in matter. Whats to stop them from using a mirror behind a ship and reflecting the laser to propel the ship? It might not be the right thing to do but we could even shove a graphene sponge in the narrow end of the cavity and let that magnetron go. Well I diverge but my question is regarding the CoM and CoE argument.
Quote from: Paul Novy on 05/28/2015 07:49 amI'm just gonna leave this here..."Macroscopic and Direct Light Propulsion of Bulk Graphene Material"http://arxiv.org/ftp/arxiv/papers/1505/1505.04254.pdfQuoteThe force generated from such a process/mechanism is muchlarger than the force generated directly from the conventional light pressure, which ismuch smaller than the force required to propel the samples. QuoteThe mechanism behind this novel phenomenon is believed to be anefficient light-induced ejected electron emission process, following an Auger-like pathdue to both the unique band structure of graphene and its macroscopic morphology ofthis unique material. This article is showing that for certain types of materials, light can impart more force to the material, than it would if it were simply used to as a photon rocket to push the same material. The difference is the Auger Effect, where the incoming light causes a population inversion in the material, that then causes electrons to be ejected from the material, greatly increasing the force by many orders of magnitude. Perhaps a similar effect can be obtained asymmetrically in a cavity?Thank you for posting it!Todd
I'm just gonna leave this here..."Macroscopic and Direct Light Propulsion of Bulk Graphene Material"http://arxiv.org/ftp/arxiv/papers/1505/1505.04254.pdfQuoteThe force generated from such a process/mechanism is muchlarger than the force generated directly from the conventional light pressure, which ismuch smaller than the force required to propel the samples. QuoteThe mechanism behind this novel phenomenon is believed to be anefficient light-induced ejected electron emission process, following an Auger-like pathdue to both the unique band structure of graphene and its macroscopic morphology ofthis unique material.
The force generated from such a process/mechanism is muchlarger than the force generated directly from the conventional light pressure, which ismuch smaller than the force required to propel the samples.
The mechanism behind this novel phenomenon is believed to be anefficient light-induced ejected electron emission process, following an Auger-like pathdue to both the unique band structure of graphene and its macroscopic morphology ofthis unique material.
Quote from: WarpTech on 05/29/2015 05:27 pmQuote from: Flyby on 05/29/2015 04:12 pmQuote from: WarpTech on 05/29/2015 01:46 pmThe interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.Todd, although I understood the general lines of the mechanism you're describing, I'm a bit confused about the frequency shifting. Initially you said that the shape of the cavity was the reason for the attenuation of the waves, where now you seem to put the wavelength shift to thermal causes?Furthermore, doesn't the heat have a negative impact on the Q ? with a higher Q, you can store more energy in the standing waves, but more energy means more heat... At some point they must equalize eachother, no? That would also mean that Shawyer's projections of having Q's running into the millions will probably never materialize?Unless there are other ways to achieve attenuation without the thermo effects?I believe that if the frustum were perfectly conductive, with no thermal losses at all, there would be no thrust. The reason being, the lowest frequency injected is still above the cut-off of the small end. So the attenuation would be minimal, but when there is thermal dissipation there is scattering of the microwaves that cause them to lose energy and shift to lower frequency and stretch to longer wavelengths that are strongly attenuated toward the front. Higher Q means more available energy in this bandwidth of evanescent waves.As I said, I am learning. I don't have all the answers and I tend to think out-loud. These discussions help me a lot but please take them with a grain of salt, until I publish a paper! Thanks!But now you appear to not be considering the paper by Zeng and Fan. Please recall that Zeng and Fan derive attenuation (and phase) coefficients that are not due to resistive losses or dielectric losses leading to heating.No, instead they derive attenuation (and phase) coefficients purely due to the geometrical shape;alpha + j beta = - (1/E) dE/drwhere "d" is the partial derivative, and E represents the Electric field in the TE or TM modes.They express this attenuation as Hankel functions purely due to geometry, attenuation due to evanescent waves, due to the change in the Electric field in the longitudinal direction.The attenuation considered by Zeng and Fan is due to modes reaching cut-off in the truncated cone as one approaches the small end of the truncated cone. As this happens, it appears that there could be an exchange from standing waves to evanescent waves.Obviously, in a cylinder dE/dr (where r is the spherical radial coordinate) is zero, so in a cylinder there is no geometrical attenuation. However, truncated cones having a small cone angle appear to have the most attenuation.
Obviously, in a cylinder dE/dr (where r is the spherical radial coordinate) is zero
...How would you consider converting the standing waves to evanescent waves? What mechanism would you choose?Todd
Quote from: Rodal on 05/29/2015 05:42 pmQuote from: WarpTech on 05/29/2015 05:27 pmQuote from: Flyby on 05/29/2015 04:12 pmQuote from: WarpTech on 05/29/2015 01:46 pmThe interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.Todd, although I understood the general lines of the mechanism you're describing, I'm a bit confused about the frequency shifting. Initially you said that the shape of the cavity was the reason for the attenuation of the waves, where now you seem to put the wavelength shift to thermal causes?Furthermore, doesn't the heat have a negative impact on the Q ? with a higher Q, you can store more energy in the standing waves, but more energy means more heat... At some point they must equalize eachother, no? That would also mean that Shawyer's projections of having Q's running into the millions will probably never materialize?Unless there are other ways to achieve attenuation without the thermo effects?I believe that if the frustum were perfectly conductive, with no thermal losses at all, there would be no thrust. The reason being, the lowest frequency injected is still above the cut-off of the small end. So the attenuation would be minimal, but when there is thermal dissipation there is scattering of the microwaves that cause them to lose energy and shift to lower frequency and stretch to longer wavelengths that are strongly attenuated toward the front. Higher Q means more available energy in this bandwidth of evanescent waves.As I said, I am learning. I don't have all the answers and I tend to think out-loud. These discussions help me a lot but please take them with a grain of salt, until I publish a paper! Thanks!But now you appear to not be considering the paper by Zeng and Fan. Please recall that Zeng and Fan derive attenuation (and phase) coefficients that are not due to resistive losses or dielectric losses leading to heating.No, instead they derive attenuation (and phase) coefficients purely due to the geometrical shape;alpha + j beta = - (1/E) dE/drwhere "d" is the partial derivative, and E represents the Electric field in the TE or TM modes.They express this attenuation as Hankel functions purely due to geometry, attenuation due to evanescent waves, due to the change in the Electric field in the longitudinal direction.The attenuation considered by Zeng and Fan is due to modes reaching cut-off in the truncated cone as one approaches the small end of the truncated cone. As this happens, it appears that there could be an exchange from standing waves to evanescent waves.Obviously, in a cylinder dE/dr (where r is the spherical radial coordinate) is zero, so in a cylinder there is no geometrical attenuation. However, truncated cones having a small cone angle appear to have the most attenuation.What I'm saying is, standing waves are not evanescent waves. The standing waves in TE013 mode have frequency well above the cut-off of the cavity. I do not know precisely "how" standing waves can be shifted to a longer wavelength where they can become evanescent waves, without a mechanism for those waves to lose energy, i.e, dissipation before attenuation. I'll have to go re-read Zeng and Fan again, but their derivation is for waves propagating down a tapered waveguide, not standing waves in a cavity. I do not assume that the standing waves will be attenuated, based on what I remember of their results. I am assuming that dissipation will cause the standing wave to decay to longer wavelength, where attenuation can take place. Only the evanescent waves, not the standing waves can produce thrust.How would you consider converting the standing waves to evanescents? What mechanism would you choose?Todd