Quote from: Rodal on 05/04/2015 05:47 PMQuote from: TheTraveller on 05/04/2015 05:45 PMQuote from: Rodal on 05/04/2015 05:27 PMQuote from: TheTraveller on 05/04/2015 05:24 PMWould seem from Shawyers latest presentation, recently shared by Mulletron, that flat end plates are out and convex / concave end plates are the new standard to reduce cavity losses and boost cavity Q / thrust generation per kW of cavity stored microwave energy.While Shawyer did share this cavity variation applied to a superconducting cavity, why it was used and what the curves are based on is new information. Would seem to make very good sense to incorporate it into non superconducting cavities.NOT NEW information at all.Discussed already much earlier in the thread. I pointed out the reason. Please take a look at the ends of the truncated cone in my exact solutions and also in Greg Egan's.The reason for the spherical ends is because the standing waves in a truncated cone cavity are spherical waves (this is known since the 1930's as per Shelkunoff's analysis)Is it not new information from Shawyer?I plan to build and test a Shawyer EM Drive with his new convex / concave end plates. Will take my design lead 100% from Shawyer at 1st as he is the only source that has built multiple EM Drives, measured generated significant force / thrust and shared enough real / practical data to allow replication of his many years of blood, sweat and tears.The theory talk here is good background but not focused enough to be something an engineer can use to built a successful working EM Drive, at least not in the 1st instance. I believe in not reinventing the wheel, until I have several working wheels to do further development from.I also plan to duplicate Shawyers vertical force measurement system as used in his Flight Thruster qualification. To me that is a very KISS solution.Would welcome any suggestions as I have read others here have started down this pathway.No, the information you posted from Shawyer was not new information on this thread.The information you posted on Shawyer's including Shawyer's presentation (which dates 6 months ago) has been discussed multiple times in this thread.One of the discussions was with an European Architect/Designer. We also discussed paraboloid cavities, for example.We are talking about the same presentation that Mullerton just received from Shawyer and posted a day ago? The attached information was known 6 months ago?

Quote from: TheTraveller on 05/04/2015 05:45 PMQuote from: Rodal on 05/04/2015 05:27 PMQuote from: TheTraveller on 05/04/2015 05:24 PMWould seem from Shawyers latest presentation, recently shared by Mulletron, that flat end plates are out and convex / concave end plates are the new standard to reduce cavity losses and boost cavity Q / thrust generation per kW of cavity stored microwave energy.While Shawyer did share this cavity variation applied to a superconducting cavity, why it was used and what the curves are based on is new information. Would seem to make very good sense to incorporate it into non superconducting cavities.NOT NEW information at all.Discussed already much earlier in the thread. I pointed out the reason. Please take a look at the ends of the truncated cone in my exact solutions and also in Greg Egan's.The reason for the spherical ends is because the standing waves in a truncated cone cavity are spherical waves (this is known since the 1930's as per Shelkunoff's analysis)Is it not new information from Shawyer?I plan to build and test a Shawyer EM Drive with his new convex / concave end plates. Will take my design lead 100% from Shawyer at 1st as he is the only source that has built multiple EM Drives, measured generated significant force / thrust and shared enough real / practical data to allow replication of his many years of blood, sweat and tears.The theory talk here is good background but not focused enough to be something an engineer can use to built a successful working EM Drive, at least not in the 1st instance. I believe in not reinventing the wheel, until I have several working wheels to do further development from.I also plan to duplicate Shawyers vertical force measurement system as used in his Flight Thruster qualification. To me that is a very KISS solution.Would welcome any suggestions as I have read others here have started down this pathway.No, the information you posted from Shawyer was not new information on this thread.The information you posted on Shawyer's including Shawyer's presentation (which dates 6 months ago) has been discussed multiple times in this thread.One of the discussions was with an European Architect/Designer. We also discussed paraboloid cavities, for example.

Quote from: Rodal on 05/04/2015 05:27 PMQuote from: TheTraveller on 05/04/2015 05:24 PMWould seem from Shawyers latest presentation, recently shared by Mulletron, that flat end plates are out and convex / concave end plates are the new standard to reduce cavity losses and boost cavity Q / thrust generation per kW of cavity stored microwave energy.While Shawyer did share this cavity variation applied to a superconducting cavity, why it was used and what the curves are based on is new information. Would seem to make very good sense to incorporate it into non superconducting cavities.NOT NEW information at all.Discussed already much earlier in the thread. I pointed out the reason. Please take a look at the ends of the truncated cone in my exact solutions and also in Greg Egan's.The reason for the spherical ends is because the standing waves in a truncated cone cavity are spherical waves (this is known since the 1930's as per Shelkunoff's analysis)Is it not new information from Shawyer?I plan to build and test a Shawyer EM Drive with his new convex / concave end plates. Will take my design lead 100% from Shawyer at 1st as he is the only source that has built multiple EM Drives, measured generated significant force / thrust and shared enough real / practical data to allow replication of his many years of blood, sweat and tears.The theory talk here is good background but not focused enough to be something an engineer can use to built a successful working EM Drive, at least not in the 1st instance. I believe in not reinventing the wheel, until I have several working wheels to do further development from.I also plan to duplicate Shawyers vertical force measurement system as used in his Flight Thruster qualification. To me that is a very KISS solution.Would welcome any suggestions as I have read others here have started down this pathway.

Quote from: TheTraveller on 05/04/2015 05:24 PMWould seem from Shawyers latest presentation, recently shared by Mulletron, that flat end plates are out and convex / concave end plates are the new standard to reduce cavity losses and boost cavity Q / thrust generation per kW of cavity stored microwave energy.While Shawyer did share this cavity variation applied to a superconducting cavity, why it was used and what the curves are based on is new information. Would seem to make very good sense to incorporate it into non superconducting cavities.NOT NEW information at all.Discussed already much earlier in the thread. I pointed out the reason. Please take a look at the ends of the truncated cone in my exact solutions and also in Greg Egan's.The reason for the spherical ends is because the standing waves in a truncated cone cavity are spherical waves (this is known since the 1930's as per Shelkunoff's analysis)

Would seem from Shawyers latest presentation, recently shared by Mulletron, that flat end plates are out and convex / concave end plates are the new standard to reduce cavity losses and boost cavity Q / thrust generation per kW of cavity stored microwave energy.While Shawyer did share this cavity variation applied to a superconducting cavity, why it was used and what the curves are based on is new information. Would seem to make very good sense to incorporate it into non superconducting cavities.

The cavity comprises a small convex end plate, a truncated conical side wall section, and a large convex end plate. The end plate Radii R1 and R2 are selected such that R2-R1 = L1 where L1 is the length of the side wall. This geometry ensures that the EM wavefront propagates between the end plates with every point on the wavefront travelling along a radius line of length L1, centred at point O. This constant path length over the wavefront ensures that phase distortion over the very large number of reflections within a high Q cavity, is minimised, and the value of Q that is achieved in practice approaches the theoretical maximum. Note that this configuration ensures that there is no orthogonal component of the guide velocity reflected from the side wall, thus ensuring a zero side wall force component in the axial plane.

Quote from: TheTraveller on 05/04/2015 05:50 PMQuote from: Rodal on 05/04/2015 05:47 PMQuote from: TheTraveller on 05/04/2015 05:45 PMQuote from: Rodal on 05/04/2015 05:27 PMQuote from: TheTraveller on 05/04/2015 05:24 PMWould seem from Shawyers latest presentation, recently shared by Mulletron, that flat end plates are out and convex / concave end plates are the new standard to reduce cavity losses and boost cavity Q / thrust generation per kW of cavity stored microwave energy.While Shawyer did share this cavity variation applied to a superconducting cavity, why it was used and what the curves are based on is new information. Would seem to make very good sense to incorporate it into non superconducting cavities.NOT NEW information at all.Discussed already much earlier in the thread. I pointed out the reason. Please take a look at the ends of the truncated cone in my exact solutions and also in Greg Egan's.The reason for the spherical ends is because the standing waves in a truncated cone cavity are spherical waves (this is known since the 1930's as per Shelkunoff's analysis)Is it not new information from Shawyer?I plan to build and test a Shawyer EM Drive with his new convex / concave end plates. Will take my design lead 100% from Shawyer at 1st as he is the only source that has built multiple EM Drives, measured generated significant force / thrust and shared enough real / practical data to allow replication of his many years of blood, sweat and tears.The theory talk here is good background but not focused enough to be something an engineer can use to built a successful working EM Drive, at least not in the 1st instance. I believe in not reinventing the wheel, until I have several working wheels to do further development from.I also plan to duplicate Shawyers vertical force measurement system as used in his Flight Thruster qualification. To me that is a very KISS solution.Would welcome any suggestions as I have read others here have started down this pathway.No, the information you posted from Shawyer was not new information on this thread.The information you posted on Shawyer's including Shawyer's presentation (which dates 6 months ago) has been discussed multiple times in this thread.One of the discussions was with an European Architect/Designer. We also discussed paraboloid cavities, for example.We are talking about the same presentation that Mullerton just received from Shawyer and posted a day ago? The attached information was known 6 months ago?Never discussed before:QuoteThe cavity comprises a small convex end plate, a truncated conical side wall section, and a large convex end plate. The end plate Radii R1 and R2 are selected such that R2-R1 = L1 where L1 is the length of the side wall. This geometry ensures that the EM wavefront propagates between the end plates with every point on the wavefront travelling along a radius line of length L1, centred at point O. This constant path length over the wavefront ensures that phase distortion over the very large number of reflections within a high Q cavity, is minimised, and the value of Q that is achieved in practice approaches the theoretical maximum. Note that this configuration ensures that there is no orthogonal component of the guide velocity reflected from the side wall, thus ensuring a zero side wall force component in the axial plane.Source IAC-14 paper:http://tinyurl.com/ofl4527

Chinese did report their cavity bandwidth data: http://www.emdrive.com/yang-juan-paper-2012.pdf

Quote from: TheTraveller on 05/04/2015 04:51 PMChinese did report their cavity bandwidth data: http://www.emdrive.com/yang-juan-paper-2012.pdfInteresting. Earlier in the first thread the discussion centered around cavity Q and the need for a high Q. This cavity only has a Q = 1531.

Quote from: zen-in on 05/04/2015 07:21 PMQuote from: TheTraveller on 05/04/2015 04:51 PMChinese did report their cavity bandwidth data: http://www.emdrive.com/yang-juan-paper-2012.pdfInteresting. Earlier in the first thread the discussion centered around cavity Q and the need for a high Q. This cavity only has a Q = 1531.The 2013 paper from NWPU: "It was found that the thrustercavity made by copper and resonating on the equivalent TE011mode has a quality factor 320400 and generates total net EMthrust 411 mN for 1000 W 2.45 GHz incident microwave." http://iopscience.iop.org/1674-1056/22/5/050301

Quote from: Rodal on 05/04/2015 06:50 PMQuote from: WarpTech on 05/04/2015 04:46 AMQuote from: ppnl on 05/04/2015 04:14 AMQuote from: WarpTech on 05/04/2015 03:55 AMQuote from: LasJayhawk on 05/03/2015 05:43 AMSo this made me think about the time I took a 3 port circulator apart. For those that are not familiar with circulators, the work like this:Put power in port 1 and it comes out port 2, put it in 2 and it comes out 3, put it in 3 and it comes out 1. All with out much loss. But if you try to go backwards, say 3 to 2, you loose 99% of the power. Cool little device. So when I take it apart all it is is a flat triangle of copper, 2 triangle shaped pieces of ferrite, and a magnet.If you don't know the math behind it, is looks at first blush as "silly" as the emdrive. No way could it do that. But it does. This thing may well work, we just don't know the math.I'm an Engineer and I've studied the Polarizable Vacuum Model of General Relativity. What it would say is the following;As a waveguide, the group velocity is something like;v_g = c x sqrt(1 - (c/2d*f)^2)Where, c is the usual speed of light, d is the diameter of the cylinder, and f is the frequency of the microwave excitation.c/2d = fc, is the Low cut-off frequency of the waveguide. The refractive index depends on the Low cut-off frequency as a function of the diameter, K = 1/sqrt( 1 - (fc/f)^2)For f >> fc, K~1. But for frequencies in the band fc1 < f <~ fc2, K is much larger.There is a strong gradient in the refractive index from one end of the cone to the other. This "mimics" gravity, as interpreted in the PV Model.Therefore, we can assume there is a "gravitational" gradient in the microwave band refractive index, along the length of the cone. At one end they have diameter d1, and at the other end they have diameter d2, and d1 > d2. Below fc1, the mode frequencies exponentially decay to zero. Just like the Casimir effect.Here is how it conserves momentum;In the PV Model, momentum transforms as,p => p*sqrt(K)In a resonant cavity, p is the SUM of all the photons “in phase", minus the losses of the cavity. However, as photons “fall” from the large end toward the small end, they gain momentum, which is passed on to the cone when they are reflected from the small end. The photon then loses momentum as it travels back to the large end, where it imparts “less” momentum to the large end. The result is a NET propulsion in the direction of the small end. In other words, the photons are blue-shifted falling forward, and red-shifted going backwards, due to the gradient in the refractive index. It is literally gravitational red & blue shift, according to the PV Model.The interesting thing is, the refractive index in the waveguide does not depend on the power of the microwaves, or the energy density. It is simply a matter of the geometry and frequency band relative to the cut-off. What matters more, is having enough resonant momentum stored to make the effect noticeable.That’s IMHO as an engineer of course. Any comments?See PV Model: https://www.researchgate.net/publication/223130116_Advanced_Space_Propulsion_Based_on_Vacuum_%28Spacetime_Metric%29_EngineeringTodd D.In what sense does this conserve momentum?Treat the device as a black box. I don't know or care what is happening inside it. At time T0 it has no momentum. Turn it on and let it accelerate so that it has some velocity and so momentum at time T1. Unless you can point to something with the same amount of momentum going in the other direction then by definition you have violated conservation of momentum. What happens inside the box simple does not affect that fact.When you drop an object and it falls to the ground. Relative to you, it gained momentum from the gravitational field. It did not expel any propellant to fall. The gravitational field is simply a gradient in the refractive index of the vacuum surrounding the Earth. If you can explain conservation of momentum for falling objects in a gravitational field, then you have your answer.(Edit) In other words, if the cavity were not tapered, then you have equal momentum inside traveling left and right. At T0, it will go nowhere. However, because it is tapered such that you have a gradient in the refractive index, then "just like gravity", photons will be blue shifted moving into higher K, and red shifted moving into lower K, because momentum,p => p*sqrt(K)THIS is a violation of conservation of momentum. Therefore, the cavity must move to conserve momentum, as it tries to establish equilibrium with it's own internal stress.Regards,Todd D.What would be the equation for the acceleration or the force, given the geometrical dimensions of the truncated cone, the Q, the input power, the frequency, and any other variables? Do you have a closed-form solution that could be compared to actual experimental results and also compared with the equation of Shawyer, and also to the equation of McCulloch ?Regards,JRNot yet... I'm just now coming to grips with this myself. My light-bulb went off when I realized if the frequency of the microwaves is very close to the cut-off frequencies, then the speed of light will have a very large gradient inside the Frustum. Relative to the "traveling" waves (photons) attempting to move at the speed of light from end to end. When they approach the small end, their wavelength is squeezed by the reduced group velocity. Momentum depends on wavelength;p = h/lambdawavelength depends on velocity, and v_g is a variable inside the frustum. That is where the momentum is coming from. Inside the Frustum, relative to the traveling waves you have an accelerated reference frame, into which you are injecting photons that are affected by this manufactured "gravitational" field, that must be compensated for by moving the Frustum.I'll see what I can come up with for a formal equation, but I've got a day job. As for @ppnl, you will never get a Newtonian-type COM equation out of this. The two frames are the Frustum, and the frame of the moving photons inside it. The acceleration is caused by the geometry of the waveguide or a variable refractive index, i.e. the GR or PV Interpretation lead to the same result.Todd D.

Quote from: WarpTech on 05/04/2015 04:46 AMQuote from: ppnl on 05/04/2015 04:14 AMQuote from: WarpTech on 05/04/2015 03:55 AMQuote from: LasJayhawk on 05/03/2015 05:43 AMSo this made me think about the time I took a 3 port circulator apart. For those that are not familiar with circulators, the work like this:Put power in port 1 and it comes out port 2, put it in 2 and it comes out 3, put it in 3 and it comes out 1. All with out much loss. But if you try to go backwards, say 3 to 2, you loose 99% of the power. Cool little device. So when I take it apart all it is is a flat triangle of copper, 2 triangle shaped pieces of ferrite, and a magnet.If you don't know the math behind it, is looks at first blush as "silly" as the emdrive. No way could it do that. But it does. This thing may well work, we just don't know the math.I'm an Engineer and I've studied the Polarizable Vacuum Model of General Relativity. What it would say is the following;As a waveguide, the group velocity is something like;v_g = c x sqrt(1 - (c/2d*f)^2)Where, c is the usual speed of light, d is the diameter of the cylinder, and f is the frequency of the microwave excitation.c/2d = fc, is the Low cut-off frequency of the waveguide. The refractive index depends on the Low cut-off frequency as a function of the diameter, K = 1/sqrt( 1 - (fc/f)^2)For f >> fc, K~1. But for frequencies in the band fc1 < f <~ fc2, K is much larger.There is a strong gradient in the refractive index from one end of the cone to the other. This "mimics" gravity, as interpreted in the PV Model.Therefore, we can assume there is a "gravitational" gradient in the microwave band refractive index, along the length of the cone. At one end they have diameter d1, and at the other end they have diameter d2, and d1 > d2. Below fc1, the mode frequencies exponentially decay to zero. Just like the Casimir effect.Here is how it conserves momentum;In the PV Model, momentum transforms as,p => p*sqrt(K)In a resonant cavity, p is the SUM of all the photons “in phase", minus the losses of the cavity. However, as photons “fall” from the large end toward the small end, they gain momentum, which is passed on to the cone when they are reflected from the small end. The photon then loses momentum as it travels back to the large end, where it imparts “less” momentum to the large end. The result is a NET propulsion in the direction of the small end. In other words, the photons are blue-shifted falling forward, and red-shifted going backwards, due to the gradient in the refractive index. It is literally gravitational red & blue shift, according to the PV Model.The interesting thing is, the refractive index in the waveguide does not depend on the power of the microwaves, or the energy density. It is simply a matter of the geometry and frequency band relative to the cut-off. What matters more, is having enough resonant momentum stored to make the effect noticeable.That’s IMHO as an engineer of course. Any comments?See PV Model: https://www.researchgate.net/publication/223130116_Advanced_Space_Propulsion_Based_on_Vacuum_%28Spacetime_Metric%29_EngineeringTodd D.In what sense does this conserve momentum?Treat the device as a black box. I don't know or care what is happening inside it. At time T0 it has no momentum. Turn it on and let it accelerate so that it has some velocity and so momentum at time T1. Unless you can point to something with the same amount of momentum going in the other direction then by definition you have violated conservation of momentum. What happens inside the box simple does not affect that fact.When you drop an object and it falls to the ground. Relative to you, it gained momentum from the gravitational field. It did not expel any propellant to fall. The gravitational field is simply a gradient in the refractive index of the vacuum surrounding the Earth. If you can explain conservation of momentum for falling objects in a gravitational field, then you have your answer.(Edit) In other words, if the cavity were not tapered, then you have equal momentum inside traveling left and right. At T0, it will go nowhere. However, because it is tapered such that you have a gradient in the refractive index, then "just like gravity", photons will be blue shifted moving into higher K, and red shifted moving into lower K, because momentum,p => p*sqrt(K)THIS is a violation of conservation of momentum. Therefore, the cavity must move to conserve momentum, as it tries to establish equilibrium with it's own internal stress.Regards,Todd D.What would be the equation for the acceleration or the force, given the geometrical dimensions of the truncated cone, the Q, the input power, the frequency, and any other variables? Do you have a closed-form solution that could be compared to actual experimental results and also compared with the equation of Shawyer, and also to the equation of McCulloch ?Regards,JR

Quote from: ppnl on 05/04/2015 04:14 AMQuote from: WarpTech on 05/04/2015 03:55 AMQuote from: LasJayhawk on 05/03/2015 05:43 AMSo this made me think about the time I took a 3 port circulator apart. For those that are not familiar with circulators, the work like this:Put power in port 1 and it comes out port 2, put it in 2 and it comes out 3, put it in 3 and it comes out 1. All with out much loss. But if you try to go backwards, say 3 to 2, you loose 99% of the power. Cool little device. So when I take it apart all it is is a flat triangle of copper, 2 triangle shaped pieces of ferrite, and a magnet.If you don't know the math behind it, is looks at first blush as "silly" as the emdrive. No way could it do that. But it does. This thing may well work, we just don't know the math.I'm an Engineer and I've studied the Polarizable Vacuum Model of General Relativity. What it would say is the following;As a waveguide, the group velocity is something like;v_g = c x sqrt(1 - (c/2d*f)^2)Where, c is the usual speed of light, d is the diameter of the cylinder, and f is the frequency of the microwave excitation.c/2d = fc, is the Low cut-off frequency of the waveguide. The refractive index depends on the Low cut-off frequency as a function of the diameter, K = 1/sqrt( 1 - (fc/f)^2)For f >> fc, K~1. But for frequencies in the band fc1 < f <~ fc2, K is much larger.There is a strong gradient in the refractive index from one end of the cone to the other. This "mimics" gravity, as interpreted in the PV Model.Therefore, we can assume there is a "gravitational" gradient in the microwave band refractive index, along the length of the cone. At one end they have diameter d1, and at the other end they have diameter d2, and d1 > d2. Below fc1, the mode frequencies exponentially decay to zero. Just like the Casimir effect.Here is how it conserves momentum;In the PV Model, momentum transforms as,p => p*sqrt(K)In a resonant cavity, p is the SUM of all the photons “in phase", minus the losses of the cavity. However, as photons “fall” from the large end toward the small end, they gain momentum, which is passed on to the cone when they are reflected from the small end. The photon then loses momentum as it travels back to the large end, where it imparts “less” momentum to the large end. The result is a NET propulsion in the direction of the small end. In other words, the photons are blue-shifted falling forward, and red-shifted going backwards, due to the gradient in the refractive index. It is literally gravitational red & blue shift, according to the PV Model.The interesting thing is, the refractive index in the waveguide does not depend on the power of the microwaves, or the energy density. It is simply a matter of the geometry and frequency band relative to the cut-off. What matters more, is having enough resonant momentum stored to make the effect noticeable.That’s IMHO as an engineer of course. Any comments?See PV Model: https://www.researchgate.net/publication/223130116_Advanced_Space_Propulsion_Based_on_Vacuum_%28Spacetime_Metric%29_EngineeringTodd D.In what sense does this conserve momentum?Treat the device as a black box. I don't know or care what is happening inside it. At time T0 it has no momentum. Turn it on and let it accelerate so that it has some velocity and so momentum at time T1. Unless you can point to something with the same amount of momentum going in the other direction then by definition you have violated conservation of momentum. What happens inside the box simple does not affect that fact.When you drop an object and it falls to the ground. Relative to you, it gained momentum from the gravitational field. It did not expel any propellant to fall. The gravitational field is simply a gradient in the refractive index of the vacuum surrounding the Earth. If you can explain conservation of momentum for falling objects in a gravitational field, then you have your answer.(Edit) In other words, if the cavity were not tapered, then you have equal momentum inside traveling left and right. At T0, it will go nowhere. However, because it is tapered such that you have a gradient in the refractive index, then "just like gravity", photons will be blue shifted moving into higher K, and red shifted moving into lower K, because momentum,p => p*sqrt(K)THIS is a violation of conservation of momentum. Therefore, the cavity must move to conserve momentum, as it tries to establish equilibrium with it's own internal stress.Regards,Todd D.

Quote from: WarpTech on 05/04/2015 03:55 AMQuote from: LasJayhawk on 05/03/2015 05:43 AMSo this made me think about the time I took a 3 port circulator apart. For those that are not familiar with circulators, the work like this:Put power in port 1 and it comes out port 2, put it in 2 and it comes out 3, put it in 3 and it comes out 1. All with out much loss. But if you try to go backwards, say 3 to 2, you loose 99% of the power. Cool little device. So when I take it apart all it is is a flat triangle of copper, 2 triangle shaped pieces of ferrite, and a magnet.If you don't know the math behind it, is looks at first blush as "silly" as the emdrive. No way could it do that. But it does. This thing may well work, we just don't know the math.I'm an Engineer and I've studied the Polarizable Vacuum Model of General Relativity. What it would say is the following;As a waveguide, the group velocity is something like;v_g = c x sqrt(1 - (c/2d*f)^2)Where, c is the usual speed of light, d is the diameter of the cylinder, and f is the frequency of the microwave excitation.c/2d = fc, is the Low cut-off frequency of the waveguide. The refractive index depends on the Low cut-off frequency as a function of the diameter, K = 1/sqrt( 1 - (fc/f)^2)For f >> fc, K~1. But for frequencies in the band fc1 < f <~ fc2, K is much larger.There is a strong gradient in the refractive index from one end of the cone to the other. This "mimics" gravity, as interpreted in the PV Model.Therefore, we can assume there is a "gravitational" gradient in the microwave band refractive index, along the length of the cone. At one end they have diameter d1, and at the other end they have diameter d2, and d1 > d2. Below fc1, the mode frequencies exponentially decay to zero. Just like the Casimir effect.Here is how it conserves momentum;In the PV Model, momentum transforms as,p => p*sqrt(K)In a resonant cavity, p is the SUM of all the photons “in phase", minus the losses of the cavity. However, as photons “fall” from the large end toward the small end, they gain momentum, which is passed on to the cone when they are reflected from the small end. The photon then loses momentum as it travels back to the large end, where it imparts “less” momentum to the large end. The result is a NET propulsion in the direction of the small end. In other words, the photons are blue-shifted falling forward, and red-shifted going backwards, due to the gradient in the refractive index. It is literally gravitational red & blue shift, according to the PV Model.The interesting thing is, the refractive index in the waveguide does not depend on the power of the microwaves, or the energy density. It is simply a matter of the geometry and frequency band relative to the cut-off. What matters more, is having enough resonant momentum stored to make the effect noticeable.That’s IMHO as an engineer of course. Any comments?See PV Model: https://www.researchgate.net/publication/223130116_Advanced_Space_Propulsion_Based_on_Vacuum_%28Spacetime_Metric%29_EngineeringTodd D.In what sense does this conserve momentum?Treat the device as a black box. I don't know or care what is happening inside it. At time T0 it has no momentum. Turn it on and let it accelerate so that it has some velocity and so momentum at time T1. Unless you can point to something with the same amount of momentum going in the other direction then by definition you have violated conservation of momentum. What happens inside the box simple does not affect that fact.

Quote from: LasJayhawk on 05/03/2015 05:43 AMSo this made me think about the time I took a 3 port circulator apart. For those that are not familiar with circulators, the work like this:Put power in port 1 and it comes out port 2, put it in 2 and it comes out 3, put it in 3 and it comes out 1. All with out much loss. But if you try to go backwards, say 3 to 2, you loose 99% of the power. Cool little device. So when I take it apart all it is is a flat triangle of copper, 2 triangle shaped pieces of ferrite, and a magnet.If you don't know the math behind it, is looks at first blush as "silly" as the emdrive. No way could it do that. But it does. This thing may well work, we just don't know the math.I'm an Engineer and I've studied the Polarizable Vacuum Model of General Relativity. What it would say is the following;As a waveguide, the group velocity is something like;v_g = c x sqrt(1 - (c/2d*f)^2)Where, c is the usual speed of light, d is the diameter of the cylinder, and f is the frequency of the microwave excitation.c/2d = fc, is the Low cut-off frequency of the waveguide. The refractive index depends on the Low cut-off frequency as a function of the diameter, K = 1/sqrt( 1 - (fc/f)^2)For f >> fc, K~1. But for frequencies in the band fc1 < f <~ fc2, K is much larger.There is a strong gradient in the refractive index from one end of the cone to the other. This "mimics" gravity, as interpreted in the PV Model.Therefore, we can assume there is a "gravitational" gradient in the microwave band refractive index, along the length of the cone. At one end they have diameter d1, and at the other end they have diameter d2, and d1 > d2. Below fc1, the mode frequencies exponentially decay to zero. Just like the Casimir effect.Here is how it conserves momentum;In the PV Model, momentum transforms as,p => p*sqrt(K)In a resonant cavity, p is the SUM of all the photons “in phase", minus the losses of the cavity. However, as photons “fall” from the large end toward the small end, they gain momentum, which is passed on to the cone when they are reflected from the small end. The photon then loses momentum as it travels back to the large end, where it imparts “less” momentum to the large end. The result is a NET propulsion in the direction of the small end. In other words, the photons are blue-shifted falling forward, and red-shifted going backwards, due to the gradient in the refractive index. It is literally gravitational red & blue shift, according to the PV Model.The interesting thing is, the refractive index in the waveguide does not depend on the power of the microwaves, or the energy density. It is simply a matter of the geometry and frequency band relative to the cut-off. What matters more, is having enough resonant momentum stored to make the effect noticeable.That’s IMHO as an engineer of course. Any comments?See PV Model: https://www.researchgate.net/publication/223130116_Advanced_Space_Propulsion_Based_on_Vacuum_%28Spacetime_Metric%29_EngineeringTodd D.

So this made me think about the time I took a 3 port circulator apart. For those that are not familiar with circulators, the work like this:Put power in port 1 and it comes out port 2, put it in 2 and it comes out 3, put it in 3 and it comes out 1. All with out much loss. But if you try to go backwards, say 3 to 2, you loose 99% of the power. Cool little device. So when I take it apart all it is is a flat triangle of copper, 2 triangle shaped pieces of ferrite, and a magnet.If you don't know the math behind it, is looks at first blush as "silly" as the emdrive. No way could it do that. But it does. This thing may well work, we just don't know the math.

Quote from: saucyjack on 05/04/2015 04:03 PMQuote from: Mulletron on 05/04/2015 04:36 PMWould @Chris Bergin be willing to set up a private thread just for talking with Mr. Shawyer, undisturbed by outside agitators?We could create a standalone Q&A thread, like this one?http://forum.nasaspaceflight.com/index.php?topic=37295.0(Notice the format is different to a normal thread).

Quote from: Mulletron on 05/04/2015 04:36 PMWould @Chris Bergin be willing to set up a private thread just for talking with Mr. Shawyer, undisturbed by outside agitators?We could create a standalone Q&A thread, like this one?http://forum.nasaspaceflight.com/index.php?topic=37295.0(Notice the format is different to a normal thread).

Would @Chris Bergin be willing to set up a private thread just for talking with Mr. Shawyer, undisturbed by outside agitators?

Quote from: Mulletron on 05/04/2015 10:44 AMSpeaking of KM, is there anyone out there that has what it takes and is willing to volunteer and set up a wiki or something?http://en.wikipedia.org/wiki/MediaWikiI've set up a MediaWiki server before and it wasn't too bad. That is a good platform. I'm simply stretched too thin right now to try it again. My previous attempt at KM (just a simple Google Doc, which was pretty bad didn't catch on so I deleted it:https://drive.google.com/folderview?id=0B4PCfHCM1KYoTXhSUTd5ZDN2WnM&usp=sharing@Mulletron et al., I am happy to assist in this. I agree, this forum is excellent for reviewing the latest contributions by all the excellent minds here, but newer folks are finding it difficult to get a handle on how we got here over the past hundred pages. As a result some of the same questions are being re-asked repeatedly. Ideally it might become the FAQ section that was discussed previously (which @Rodal noted some valid concerns regarding). Worth a try, at least.To this end, I have set up a MediaWiki server at http://emdrive.echothis.com and will start by the adding the relevant links in today. However, I'm just a (non-practicing) mechanical engineer, not a physicist so my role in this would be limited to setting up the organization and linking to the relevant content already posted by people far more knowledgeable than I. Anyone who has been tracking the forum and would like to join in this endeavor, welcome!

Speaking of KM, is there anyone out there that has what it takes and is willing to volunteer and set up a wiki or something?http://en.wikipedia.org/wiki/MediaWikiI've set up a MediaWiki server before and it wasn't too bad. That is a good platform. I'm simply stretched too thin right now to try it again. My previous attempt at KM (just a simple Google Doc, which was pretty bad didn't catch on so I deleted it:https://drive.google.com/folderview?id=0B4PCfHCM1KYoTXhSUTd5ZDN2WnM&usp=sharing

I repost here this post which may be of interest to people here as well:Quote from: WarpTech on 05/04/2015 07:47 PMQuote from: Rodal on 05/04/2015 06:50 PMQuote from: WarpTech on 05/04/2015 04:46 AMQuote from: ppnl on 05/04/2015 04:14 AMQuote from: WarpTech on 05/04/2015 03:55 AMQuote from: LasJayhawk on 05/03/2015 05:43 AMSo this made me think about the time I took a 3 port circulator apart. For those that are not familiar with circulators, the work like this:Put power in port 1 and it comes out port 2, put it in 2 and it comes out 3, put it in 3 and it comes out 1. All with out much loss. But if you try to go backwards, say 3 to 2, you loose 99% of the power. Cool little device. So when I take it apart all it is is a flat triangle of copper, 2 triangle shaped pieces of ferrite, and a magnet.If you don't know the math behind it, is looks at first blush as "silly" as the emdrive. No way could it do that. But it does. This thing may well work, we just don't know the math.I'm an Engineer and I've studied the Polarizable Vacuum Model of General Relativity. What it would say is the following;As a waveguide, the group velocity is something like;v_g = c x sqrt(1 - (c/2d*f)^2)Where, c is the usual speed of light, d is the diameter of the cylinder, and f is the frequency of the microwave excitation.c/2d = fc, is the Low cut-off frequency of the waveguide. The refractive index depends on the Low cut-off frequency as a function of the diameter, K = 1/sqrt( 1 - (fc/f)^2)For f >> fc, K~1. But for frequencies in the band fc1 < f <~ fc2, K is much larger.There is a strong gradient in the refractive index from one end of the cone to the other. This "mimics" gravity, as interpreted in the PV Model.Therefore, we can assume there is a "gravitational" gradient in the microwave band refractive index, along the length of the cone. At one end they have diameter d1, and at the other end they have diameter d2, and d1 > d2. Below fc1, the mode frequencies exponentially decay to zero. Just like the Casimir effect.Here is how it conserves momentum;In the PV Model, momentum transforms as,p => p*sqrt(K)In a resonant cavity, p is the SUM of all the photons “in phase", minus the losses of the cavity. However, as photons “fall” from the large end toward the small end, they gain momentum, which is passed on to the cone when they are reflected from the small end. The photon then loses momentum as it travels back to the large end, where it imparts “less” momentum to the large end. The result is a NET propulsion in the direction of the small end. In other words, the photons are blue-shifted falling forward, and red-shifted going backwards, due to the gradient in the refractive index. It is literally gravitational red & blue shift, according to the PV Model.The interesting thing is, the refractive index in the waveguide does not depend on the power of the microwaves, or the energy density. It is simply a matter of the geometry and frequency band relative to the cut-off. What matters more, is having enough resonant momentum stored to make the effect noticeable.That’s IMHO as an engineer of course. Any comments?See PV Model: https://www.researchgate.net/publication/223130116_Advanced_Space_Propulsion_Based_on_Vacuum_%28Spacetime_Metric%29_EngineeringTodd D.In what sense does this conserve momentum?Treat the device as a black box. I don't know or care what is happening inside it. At time T0 it has no momentum. Turn it on and let it accelerate so that it has some velocity and so momentum at time T1. Unless you can point to something with the same amount of momentum going in the other direction then by definition you have violated conservation of momentum. What happens inside the box simple does not affect that fact.When you drop an object and it falls to the ground. Relative to you, it gained momentum from the gravitational field. It did not expel any propellant to fall. The gravitational field is simply a gradient in the refractive index of the vacuum surrounding the Earth. If you can explain conservation of momentum for falling objects in a gravitational field, then you have your answer.(Edit) In other words, if the cavity were not tapered, then you have equal momentum inside traveling left and right. At T0, it will go nowhere. However, because it is tapered such that you have a gradient in the refractive index, then "just like gravity", photons will be blue shifted moving into higher K, and red shifted moving into lower K, because momentum,p => p*sqrt(K)THIS is a violation of conservation of momentum. Therefore, the cavity must move to conserve momentum, as it tries to establish equilibrium with it's own internal stress.Regards,Todd D.What would be the equation for the acceleration or the force, given the geometrical dimensions of the truncated cone, the Q, the input power, the frequency, and any other variables? Do you have a closed-form solution that could be compared to actual experimental results and also compared with the equation of Shawyer, and also to the equation of McCulloch ?Regards,JRNot yet... I'm just now coming to grips with this myself. My light-bulb went off when I realized if the frequency of the microwaves is very close to the cut-off frequencies, then the speed of light will have a very large gradient inside the Frustum. Relative to the "traveling" waves (photons) attempting to move at the speed of light from end to end. When they approach the small end, their wavelength is squeezed by the reduced group velocity. Momentum depends on wavelength;p = h/lambdawavelength depends on velocity, and v_g is a variable inside the frustum. That is where the momentum is coming from. Inside the Frustum, relative to the traveling waves you have an accelerated reference frame, into which you are injecting photons that are affected by this manufactured "gravitational" field, that must be compensated for by moving the Frustum.I'll see what I can come up with for a formal equation, but I've got a day job. As for @ppnl, you will never get a Newtonian-type COM equation out of this. The two frames are the Frustum, and the frame of the moving photons inside it. The acceleration is caused by the geometry of the waveguide or a variable refractive index, i.e. the GR or PV Interpretation lead to the same result.Todd D.

....We have designed a cylindrical cavity to simplify the problem. Solutions to resonant freq are much easier and more intuitive in a cylinder, and hitting resonance (when we adjust the dielectric) with a constant frequency (from a microwave oven magnetron) will be possible by adjusting the height of the cylinder. ....

Quote from: zellerium on 05/04/2015 07:05 PM....We have designed a cylindrical cavity to simplify the problem. Solutions to resonant freq are much easier and more intuitive in a cylinder, and hitting resonance (when we adjust the dielectric) with a constant frequency (from a microwave oven magnetron) will be possible by adjusting the height of the cylinder. ....But a cylindrical cavity displays no attenuation and no focusing in the axial direction (unlike the truncated cone). The experimenters in the US, UK and China are using truncated cones. If you obtain no net thrust for the cylindrical cavity, will that have been worth the effort you went through (instead of testing a truncated cone, preferably with the same geometry dimensions as NASA's or one of Shaywer's ? )Concerning obtaining the frequency and mode shape, does your University give you access to a Finite Element analysis package like COMSOL, or ANSYS Multiphysics, etc. so that you could then obtain a numerical solution for any arbitrary geometry and inserted dielectric ?

Quote from: saucyjack on 05/04/2015 04:03 PMQuote from: Mulletron on 05/04/2015 10:44 AMSpeaking of KM, is there anyone out there that has what it takes and is willing to volunteer and set up a wiki or something?http://en.wikipedia.org/wiki/MediaWikiI've set up a MediaWiki server before and it wasn't too bad. That is a good platform. I'm simply stretched too thin right now to try it again. My previous attempt at KM (just a simple Google Doc, which was pretty bad didn't catch on so I deleted it:https://drive.google.com/folderview?id=0B4PCfHCM1KYoTXhSUTd5ZDN2WnM&usp=sharing@Mulletron et al., I am happy to assist in this. I agree, this forum is excellent for reviewing the latest contributions by all the excellent minds here, but newer folks are finding it difficult to get a handle on how we got here over the past hundred pages. As a result some of the same questions are being re-asked repeatedly. Ideally it might become the FAQ section that was discussed previously (which @Rodal noted some valid concerns regarding). Worth a try, at least.To this end, I have set up a MediaWiki server at http://emdrive.echothis.com and will start by the adding the relevant links in today. However, I'm just a (non-practicing) mechanical engineer, not a physicist so my role in this would be limited to setting up the organization and linking to the relevant content already posted by people far more knowledgeable than I. Anyone who has been tracking the forum and would like to join in this endeavor, welcome!I would be most happy to join this effort!Quite amusingly, I only ever look at updates on this thread during the week (worktime simulations are...boring) and this weekend I had decided that what seemed like the best thing I could do to help out the efforts here (since I'm not particularly knowledgeable with this sort of physics) would be to set up the wiki. When I showed up this morning I saw that I had a rather astounding 13+ pages of forum thread to catch up on! (Usually it seems to be about 4-5).So when I read Mulletron's suggestion my thoughts were "Ah ha! I'm on the case! But I should finish catching up first." and then I saw you had started one up.My provisional plan had been to slowly work through from page 1 again creating topics for things as they came up and beginning to organize them as the groupings became obvious.A few groupings I had identified earlier:Possible Error Sources of Thrust: Things like thermal buckling, atmospheric effects, etc would get pages of their own and this grouping would just allow for easy perusing of these topics. It might be wise to organize them into some sort of 'Busted', 'Under Investigation', 'Other' groupings. Of course new information can elevate one of the topics out of the busted area or descend it as necessary.Current Theories: Relatively simple, listing out Shawyer's, White's, the Chinese Teams, Mulletron's, etc theories on what is going on.Thrust Modes and Results: This one probably just ends up being a table of its own, but is probably particularly specific to the Eaglework's team.Status of DIY Efforts: Lets Mulletron, Notsosureofit, DIYFan, and others that are replicating this provide easy to reference status updates and other things (future plans, etc).What I was envisioning was to attempt to use the wiki-source system to provide pointers from information to the forum posts concerning them.Thoughts?

Quote from: Rodal on 05/04/2015 08:40 PMQuote from: zellerium on 05/04/2015 07:05 PM....We have designed a cylindrical cavity to simplify the problem. Solutions to resonant freq are much easier and more intuitive in a cylinder, and hitting resonance (when we adjust the dielectric) with a constant frequency (from a microwave oven magnetron) will be possible by adjusting the height of the cylinder. ....But a cylindrical cavity displays no attenuation and no focusing in the axial direction (unlike the truncated cone). The experimenters in the US, UK and China are using truncated cones. If you obtain no net thrust for the cylindrical cavity, will that have been worth the effort you went through (instead of testing a truncated cone, preferably with the same geometry dimensions as NASA's or one of Shaywer's ? )Concerning obtaining the frequency and mode shape, does your University give you access to a Finite Element analysis package like COMSOL, or ANSYS Multiphysics, etc. so that you could then obtain a numerical solution for any arbitrary geometry and inserted dielectric ?Dr. Rodal:I was under the impression that a symmetric shape should produce a net thrust, based on the null Cannae test article at EW. The only asymmetry there was the dielectric slug in the end, correct?I don't believe we have access to COMSOL, but I will look into another method. We have yet to purchase materials and may be able to test a truncated shape as well as a symmetric shape with the same copper tube and end plates.

Instead, I am focusing on the difference in parameters of each experiment--what does the thrust depend on? EW saw a clear dependence on a dielectric, but Shawyer, NWPU and Fetta observed high efficiencies without one. But why does Shawyer mention the "dielectric-filled section" in one of his papers and not reference it in later experiments? http://www.emdrive.com/theorypaper9-4.pdf Has NWPU tried their magnetron cavity using a dielectric? I believe I read a comment referencing a 2014 paper by Yang but I have not been able to find it. Did EW test without a dielectric in a vacuum?

Zellerium, I am uncertain about if your University allows for this sort of thing or not, but for the purposes of the nascent Wiki under development, would you be willing to provide (later once you have them) some Bills of Materials as well as instructions documenting how you assembled and set up your rig?

Quote from: TheTraveller on 05/04/2015 06:10 AMQuote from: Stormbringer on 05/04/2015 05:01 AMif what you say is true there is no way Boeing or anyone else involved with any form of propulsion but especially aviation or space flight would lose interest. any reduced mass is astoundingly useful. Even if the thing only reduced mass by 1 percent it would revolutionize everything. Nothing would ever be the same again. Automobiles, trains, planes, rockets; everything.Is not what I say. Is what Shawyer explains in his how to measure the forces pdf and in his explanation of how his space plane would do a 0.05g vertical lift.As another example of EM Drive ratchet mode operation, assume we had a EM Drive with a motor & generator mode maximum force generation of 9.8 Newtons and the device had a mass of 0.5kg.Now support it 1 mtr off the ground via say a small pedestal table, oriented such that the force of gravity would put the EM Drive into Generator / force resistance mode.Next switch it on.Now remove the pedestal support table.Observe it is hovering as the downward 0.5kg weight is opposed by generator mode, which has a max ability to resist 9.8 Newtons of force or 1kg of mass at the Earth's surface. So if I read you well and equivalence principle holds, having a rocket in deep space accelerating, by conventional mean, at 1g, a floor that is orthogonal to this acceleration, a pedestal resting on this floor, a powered EM drive resting on this pedestal in same configuration, remove the pedestal and one will observe the EM drive hovering above that floor (that is still accelerating at 1g). Meaning we now have a powered EM drive not needing to be "pushed" to accelerate at 1g (there is no longer any interaction between rocket and device). Stop the conventional thrust of the rocket : the rocket will stop accelerating and proceed as an inertial mass at constant velocity (relative to whatever inertial frame). Let the device escape from an open front bay : it will continue to accelerate at 1g since it was no longer interacting with the rocket when the change in acceleration of the rocket occurred (no interaction => whatever change in rocket trajectory ignored). We now have a "conventionally" accelerating (thrusting) EM drive needing no added force.So why bother with a Hall thruster ? Just put behind a big dumb powder booster that makes your EM drive accelerate at 1g for a fraction of a second the time it takes for the EM drive to "record" that acceleration as a "starting point". BTW, same argument above could be made if acceleration was 0.5g instead of 1g : this means we now have to add a new intrinsic variable to a moving object. What physical mechanism explains this memory effect of "initial acceleration" into an ongoing acceleration of given magnitude ?Quote...I trust this shows how the EM Drive is unlike anything humanity has experienced before. So please do not move forward thinking it is like a propellantless Hall thruster or rocket motor that generates thrust when the cavity is filled with microwave energy.Don't underestimate the aptitude of intelligent people to integrate counter intuitive formal systems when they show internal consistency.

Quote from: Stormbringer on 05/04/2015 05:01 AMif what you say is true there is no way Boeing or anyone else involved with any form of propulsion but especially aviation or space flight would lose interest. any reduced mass is astoundingly useful. Even if the thing only reduced mass by 1 percent it would revolutionize everything. Nothing would ever be the same again. Automobiles, trains, planes, rockets; everything.Is not what I say. Is what Shawyer explains in his how to measure the forces pdf and in his explanation of how his space plane would do a 0.05g vertical lift.As another example of EM Drive ratchet mode operation, assume we had a EM Drive with a motor & generator mode maximum force generation of 9.8 Newtons and the device had a mass of 0.5kg.Now support it 1 mtr off the ground via say a small pedestal table, oriented such that the force of gravity would put the EM Drive into Generator / force resistance mode.Next switch it on.Now remove the pedestal support table.Observe it is hovering as the downward 0.5kg weight is opposed by generator mode, which has a max ability to resist 9.8 Newtons of force or 1kg of mass at the Earth's surface.

if what you say is true there is no way Boeing or anyone else involved with any form of propulsion but especially aviation or space flight would lose interest. any reduced mass is astoundingly useful. Even if the thing only reduced mass by 1 percent it would revolutionize everything. Nothing would ever be the same again. Automobiles, trains, planes, rockets; everything.

...I trust this shows how the EM Drive is unlike anything humanity has experienced before. So please do not move forward thinking it is like a propellantless Hall thruster or rocket motor that generates thrust when the cavity is filled with microwave energy.