Quote from: StrongGR on 05/26/2015 02:55 pmMaybe I missed some information due to my delay on following these threads. What are the characteristics of the cavities used by NASA? I mean the physical dimensions, the input power (I know this is around tenth of W) and the relative dielectric constant of the material used as a dielectric (HDPE). Could the latter be similar to conjugate polymers or some ceramic material with this value ranging to some 10^5?Please find the physical dimensions of NASA's truncated cone (they have only one) here: ...
Maybe I missed some information due to my delay on following these threads. What are the characteristics of the cavities used by NASA? I mean the physical dimensions, the input power (I know this is around tenth of W) and the relative dielectric constant of the material used as a dielectric (HDPE). Could the latter be similar to conjugate polymers or some ceramic material with this value ranging to some 10^5?
While I am in favor of this Wiki, it is unfair to attribute it to me as I did not create it.That being said, I encourage all of the more advanced members of this forum to contribute, discuss, and correct issues on the wiki so that it can serve as an introduction to the topics at hand, and also show where the theoretical disagreement exist, with references to back them up.
Quote from: arc on 05/26/2015 09:17 amThought experiment: Can people please supply thoughts/feedback on the followingThis is what White and his team did with a rectangular box. The effect is there as they observed satellite frequencies of the input laser beam. I have shown this in my paper too. When you apply the idea to the computation of the thrust, for the current geometries and input powers, the gravitational effect appears to be too minuscule to account for the measured one.
Thought experiment: Can people please supply thoughts/feedback on the following
...@Chris B - Good idea to add the wiki link to the first post of this thread. Is that possible? ...
Quote from: StrongGR on 05/26/2015 09:50 amQuote from: arc on 05/26/2015 09:17 amThought experiment: Can people please supply thoughts/feedback on the followingThis is what White and his team did with a rectangular box. The effect is there as they observed satellite frequencies of the input laser beam. I have shown this in my paper too. When you apply the idea to the computation of the thrust, for the current geometries and input powers, the gravitational effect appears to be too minuscule to account for the measured one.I know Dr. white did it for a rectangular box, did you do it for the EM Frustum cavity and take into account the geometry of the cavity? And does the gravitational effect scale through the Frustum as the geometry of the cavity changes?Thanks... back to reading. Shell
Quote from: SeeShells on 05/26/2015 03:39 pmQuote from: StrongGR on 05/26/2015 09:50 amQuote from: arc on 05/26/2015 09:17 amThought experiment: Can people please supply thoughts/feedback on the followingThis is what White and his team did with a rectangular box. The effect is there as they observed satellite frequencies of the input laser beam. I have shown this in my paper too. When you apply the idea to the computation of the thrust, for the current geometries and input powers, the gravitational effect appears to be too minuscule to account for the measured one.I know Dr. white did it for a rectangular box, did you do it for the EM Frustum cavity and take into account the geometry of the cavity? And does the gravitational effect scale through the Frustum as the geometry of the cavity changes?Thanks... back to reading. ShellThe problem here is that, for gravity, all scales as G/c^4, something like 10^-43. Geometry, dielectric and all that help to mitigate by several orders of magnitude such a small number but I cannot see how to recover a thrust of the order of tenths of micronewton.
How the Maser was invented also is useful to get us to think about the nature of the EM Drive in more conventional ways. There are three keys to the Maser's operation:...It was crucial to success that the inventor of the Maser understood there would have to be a way to intensify the action. The inventor realized that this amplification could be obtained by harnessing the phenomenon of resonance of a cavity: high Q. The cavity was designed to resonate with standing waves at the same frequency of 24 GHz at which the ammonia gas energetically emits. In the reverberant space of the cavity the photons are kept rocketing back and forth through the energy-loaded gas so as to build a vigorous sustained oscillation. The 24 GHz vibration entering the cavity is amplified 100 times in power. Quote from: demofsky on 05/25/2015 05:50 pmHm. As has been noted many times both Sawyer and Yangs experiments are ran at atmospheric pressure and are furthermore (as far as anyone can tell) well sealed...One defence for this hypotheses is the difference in measured effects between the Yang and Sawyer devices and the Eagleworks vacuum tests.Quote from: ThinkerX on 05/25/2015 06:12 pmTo me, this is a really crucial bit of info. If these devices loose this much performance in a vacuum, then are they really all that superior to a photon rocket? ...It is indeed noteworthy that although Shawyer has been working on the EM Drive for decades, that no experiment in a vacuum has been reported by Mr. Shawyer. Prof. Yang has been working on EM Drive experiments since prior to 2010, yet we are in 2015 and we have not yet heard of her performing experiments in a vacuum.It took NASA Eagleworks less than a year to perform an EM Drive experiment in a vacuum and the results showed significantly less thrust/InputPower than the one measured in air.So it definitely has to be considered whether the gas molecules inside the EM Drive may not indeed be undergoing segregation between high-energy and low-energy, and whether the gas molecules may be playing a role (beyond the obvious one of air convection, gas exiting the EM Drive under higher pressure than ambient, buoyancy due to higher temperature, etc.)...http://b.gatech.edu/1cX7sXjhttp://www.mike-willis.com/Tutorial/gases.htmhttp://www.jpier.org/PIERB/pierb15/09.09041706.pdfhttp://www1.lsbu.ac.uk/water/microwave_water.html
Hm. As has been noted many times both Sawyer and Yangs experiments are ran at atmospheric pressure and are furthermore (as far as anyone can tell) well sealed...One defence for this hypotheses is the difference in measured effects between the Yang and Sawyer devices and the Eagleworks vacuum tests.
To me, this is a really crucial bit of info. If these devices loose this much performance in a vacuum, then are they really all that superior to a photon rocket? ...
For whatever it's worth, I tried also on my own using Mathematica , based on your paper, and I arrived at your same above conclusions
Quote from: frobnicat on 05/26/2015 02:13 pm...1kW photon thrust makes for only about 3µN, unless it is efficiently recycled (like photonic laser thruster by BAE) which I doubt is the case, the setup looked open enough to leak microwaves copiously around. If this is the video in question, I recall the scale registering a gram force or so, from those values I doubt this was due to just EM beamed force...I didn't recall the measured force and I couldn't find the video again to be able to check it. If he measured 1 gram, that's thousands of times better performance than a photon rocket, and as you said, it would be very noteworthy (if the measurement was not an artifact). So perhaps he pulled the video out of YouTube once he realized that what he was measuring was an artifact.I hope he didn't get hurt during the experiment.Thanks for pointing this out.
...1kW photon thrust makes for only about 3µN, unless it is efficiently recycled (like photonic laser thruster by BAE) which I doubt is the case, the setup looked open enough to leak microwaves copiously around. If this is the video in question, I recall the scale registering a gram force or so, from those values I doubt this was due to just EM beamed force...
I really think this is a critical insight. The microwave frequencies being used are specifically tailored to heat water (as everybody is basically using a home microwave oven emitter) - this may indeed be a water molecule amplified maser. The humidity at time of testing in the various locations should be measured and considered as a data point in the measured thrust.
Quote from: VAXHeadroom on 05/26/2015 03:57 pmI really think this is a critical insight. The microwave frequencies being used are specifically tailored to heat water (as everybody is basically using a home microwave oven emitter) - this may indeed be a water molecule amplified maser. The humidity at time of testing in the various locations should be measured and considered as a data point in the measured thrust.The Flight Thruster EM Drive Shawyer built for Boeing was a sealed unit and operates at 3.85GHz.http://www.emdrive.com/flightprogramme.html
I wonder if "sealed" and "gas tight" are truly synonymous here. After all, there is an RF connector (at least)
Quote from: Rodal on 05/26/2015 03:49 pmFor whatever it's worth, I tried also on my own using Mathematica , based on your paper, and I arrived at your same above conclusionsIndeed, general relativity yields a too small contribution and so, one can conclude that whatever approach one uses to recover the third principle just fails. If there will be a confirmation of this effect it will be really interesting to find a theoretical account for it. Personally, I am unconvinced.
Quote from: deltaMass on 05/26/2015 04:17 pmI wonder if "sealed" and "gas tight" are truly synonymous here. After all, there is an RF connector (at least)I'll ask Shawyer.
Quote from: StrongGR on 05/26/2015 03:57 pmQuote from: Rodal on 05/26/2015 03:49 pmFor whatever it's worth, I tried also on my own using Mathematica , based on your paper, and I arrived at your same above conclusionsIndeed, general relativity yields a too small contribution and so, one can conclude that whatever approach one uses to recover the third principle just fails. If there will be a confirmation of this effect it will be really interesting to find a theoretical account for it. Personally, I am unconvinced.Honestly, I got the old pencil and eraser out and hacked my way through it and saw the same miniscule effect. I guess I needed verification. Thanks guys
Quote from: SeeShells on 05/26/2015 04:32 pmQuote from: StrongGR on 05/26/2015 03:57 pmQuote from: Rodal on 05/26/2015 03:49 pmFor whatever it's worth, I tried also on my own using Mathematica , based on your paper, and I arrived at your same above conclusionsIndeed, general relativity yields a too small contribution and so, one can conclude that whatever approach one uses to recover the third principle just fails. If there will be a confirmation of this effect it will be really interesting to find a theoretical account for it. Personally, I am unconvinced.Honestly, I got the old pencil and eraser out and hacked my way through it and saw the same miniscule effect. I guess I needed verification. Thanks guysI hope tomorrow to post the latest version. With this, I will post also the corresponding Maple worksheet to tinkering about, if one likes. The effect is there but really too small. My guess is that more mundane explanations could be at work.
Quote from: WarpTech on 05/25/2015 08:21 pmQuote from: Notsosureofit on 05/25/2015 07:29 pm@WarpTech raises a very good point. Any system which provides propellant-less acceleration should also work as an accelerometer. Photon resonators are already used as accelerometers. (and by extension, gravity wave detectors)Exactly, that's where Dr. McCulloch's work comes in, though I'm not well versed in his model yet. Accelerating a cavity full of energy, oscillating in modes will cause a doppler shift to propagate through. Here, that doppler shift is being caused by energy lost to the cavity.Momentum is being input to the cavity via the microwaves, dp_in/dt, and is stored in the oscillating modes, Q*dp_in/dt. The rate of dissipation of that momentum, -dp/dt = F, will determine the forces on each surface. If that rate is not simply a constant of the metal, but a variable of the geometry, there will be asymmetrical forces, velocities and doppler shifts. Agreed? ToddOne thing I had almost forgotten about that Accelerometer because it's been so long since I've worked on it. IF it were possible to create a device that, when simply placed in an accelerated reference frame, it would output a voltage from which constant power could be extracted. It implies (deltaMass?) that if it were sitting on the floor in my garage, I could extract infinite energy from the gravitational field, which is an accelerated reference frame relative to the Accelerometer sitting on the floor.What happens instead is, the accelerometer becomes polarized and the charge density on the "charged objects" is no l longer evenly distributed. It cannot output more than the amount of power required to polarize it. I can input energy to depolarize it, and then extract it as it polarizes again, but I can't get free energy from it.Therefore, any propellant-less propulsion device, must have some means of becoming depolarized. In the case of the frustum, stored energy is lost to heat as well as thrust, and this eventually depolarizes it so it can be re-charged and thrust again. Once again, it can only work in a pulsed mode, when power is ramping up and down quickly.Todd
Quote from: Notsosureofit on 05/25/2015 07:29 pm@WarpTech raises a very good point. Any system which provides propellant-less acceleration should also work as an accelerometer. Photon resonators are already used as accelerometers. (and by extension, gravity wave detectors)Exactly, that's where Dr. McCulloch's work comes in, though I'm not well versed in his model yet. Accelerating a cavity full of energy, oscillating in modes will cause a doppler shift to propagate through. Here, that doppler shift is being caused by energy lost to the cavity.Momentum is being input to the cavity via the microwaves, dp_in/dt, and is stored in the oscillating modes, Q*dp_in/dt. The rate of dissipation of that momentum, -dp/dt = F, will determine the forces on each surface. If that rate is not simply a constant of the metal, but a variable of the geometry, there will be asymmetrical forces, velocities and doppler shifts. Agreed? Todd
@WarpTech raises a very good point. Any system which provides propellant-less acceleration should also work as an accelerometer. Photon resonators are already used as accelerometers. (and by extension, gravity wave detectors)