Quote from: arc on 05/11/2015 03:55 amDo higher em frequencies deliver increased net effect?Excellent question. To which as yet we have no answers. This might be taken to imply that we should find out But but but...there is no guarantee that these forces in any way combine to produce a larger force. And that's static I mean. I'm even more doubtful about the free space dynamics.Statically we care about k, or N/WDynamically we don't know what we care about yet

Do higher em frequencies deliver increased net effect?

The sciences do not try to explain, they hardly even try to interpret, they mainly make models. By a model is meant a mathematical construct which, with the addition of certain verbal interpretations, describes observed phenomena. The justification of such a mathematical construct is solely and precisely that it is expected to work.

Our understanding of conservation is very deep, and Emmie Noether discovered it. She found that for every symmetry or invariance there exists a corresponding conservation law. For momentum it's the symmetry of space. For energy it's the symmetry of time. It's actually more mathematically complex than that, since it involves differentials of the Lagrangian.http://en.wikipedia.org/wiki/Noether%27s_theoremSusskind has some public lectures about all the gory details, on YouTube.

Quote SeeShells:The second law of thermodynamics states that the entropy of an isolated system never decreases and the EM Chamber is an isolated enclosed system, we think. If we are getting thrust that, thrust must be acting outside the chamber in some form. This is why I asked the simple question if smoke was used in the tests, it wasn't to detect thermal air currents but to see if it was moving away from any thrust from the EM Chamber. Smoke is small .5 to 2 um and might be be directly effected. If not then look for other forms of accelerated energy, providing thrust emanating out of the EM Chamber. I agree with your thought train.I have a feeling that we are so busy looking at the big paw print in the dirt that we don't see the bear sneaking up behind us.Is it really the reflection/refraction of microwave photons that are the core issue here?.Or is it the expanded energy shell they carry... that any high voltage source might carry?It is obvious that the thermal state of the test device will be impacted. Is the gravitational mass of the test unit "altered" between power up/power down?. Is the "inertia" of the test device impacted?.Is the Virtual mass of the test unit altering?, the reactionary energy based mass attachment to space-time. {Mach principle}Does the chamber emit external acoustic waves? ( well beyond the human hearing range)

SeeShells:The second law of thermodynamics states that the entropy of an isolated system never decreases and the EM Chamber is an isolated enclosed system, we think. If we are getting thrust that, thrust must be acting outside the chamber in some form. This is why I asked the simple question if smoke was used in the tests, it wasn't to detect thermal air currents but to see if it was moving away from any thrust from the EM Chamber. Smoke is small .5 to 2 um and might be be directly effected. If not then look for other forms of accelerated energy, providing thrust emanating out of the EM Chamber.

Quote from: deltaMass on 05/11/2015 04:16 am@arc:QuoteDo higher em frequencies deliver increased net effect?Excellent question. To which as yet we have no answers. This might be taken to imply that we should find out But but but...there is no guarantee that these forces in any way combine to produce a larger force. And that's static I mean. I'm even more doubtful about the free space dynamics.Statically we care about k, or N/WDynamically we don't know what we care about yet We have three tentative answers. They are the mathematical formulas based on their respective theoretical models:Quote from: John von NeumannThe sciences do not try to explain, they hardly even try to interpret, they mainly make models. By a model is meant a mathematical construct which, with the addition of certain verbal interpretations, describes observed phenomena. The justification of such a mathematical construct is solely and precisely that it is expected to work.If a theory does not have a mathematical formula predicting variables, it doesn't qualify as a physical theory.The predictive formulas of Shawyer and of McCulloch both are inversely proportional to the frequency. So, on the contrary, both Shawyer and McCulloch predict that the higher the frequency the smaller the thrust force.The formulas of Shawyer and of McCulloch have no dependence on mode shape.@Notsosureofit's formula is the only formula that shows dependence on mode shape (through the Bessel zeros, Xmn or X'mn) and hence it has a more nuanced, subtle dependence on frequency. As the Bessel zeros Xmn (for TM modes) and X'mn (for TE modes) increase with frequency, @Notsosureofit's thrust force increases with frequency for mode shapes with (both) high m and n (circular and radial) quantum numbers (because Xmn and X'mn increase with frequency at a faster rate than the frequency itself) @Notsosureofit's thrust force decreases with frequency for mode shapes having (both) low m and n (circular and radial) quantum numbers (but in this case some of these low m and n mode shapes may be cut off at higher frequencies).

@arc:QuoteDo higher em frequencies deliver increased net effect?Excellent question. To which as yet we have no answers. This might be taken to imply that we should find out But but but...there is no guarantee that these forces in any way combine to produce a larger force. And that's static I mean. I'm even more doubtful about the free space dynamics.Statically we care about k, or N/WDynamically we don't know what we care about yet

Quote from: deltaMass on 05/11/2015 10:28 amOur understanding of conservation is very deep, and Emmie Noether discovered it. She found that for every symmetry or invariance there exists a corresponding conservation law. For momentum it's the symmetry of space. For energy it's the symmetry of time. It's actually more mathematically complex than that, since it involves differentials of the Lagrangian.http://en.wikipedia.org/wiki/Noether%27s_theoremSusskind has some public lectures about all the gory details, on YouTube.That's the point I want to make. We're working with a model that has proven to be correct so far, for a century. Everybody is so used to applying this powerful insight, that perception and thought patterns are fixated on it. What, for instance, if the symmetry of space is (temporarily) being changed by a device like an EM-drive? I think that such a thing might be at least in some way outside of Noether's theorem. It might all depend on whether or not the QV is immutable and indestructible. What do you think?BR,-CW

...That's a nice enumeration. But what of Sonny White's PV derivative theory - called QVF I believe?

Interesting concept, I like it. 10 stacks of "cavities" 100 units high arranged either side by side (flat/wall) or in a circular/tubular form. The tube would allow you to feed the energy up the middle to each drive unit.. 1000 micro-thrusters in Series-ParallelSounds like a 3D printing job. Glass would not stand that heat for very long... perhaps Silver?. Or Titanium with polished silver coatingEach cavity could use the wall of its neighbor for mechanical rigidity and the gaps resulting from conic shaped chambers would allow a coolant to be pumped around the cavities. Drive the units in cyclic pumped mode to minimise thermal overloading.

Quote from: deltaMass on 05/11/2015 04:16 amQuote from: arc on 05/11/2015 03:55 amDo higher em frequencies deliver increased net effect?Excellent question. To which as yet we have no answers. This might be taken to imply that we should find out But but but...there is no guarantee that these forces in any way combine to produce a larger force. And that's static I mean. I'm even more doubtful about the free space dynamics.Statically we care about k, or N/WDynamically we don't know what we care about yet We have three tentative answers. They are the mathematical formulas based on their respective theoretical models:Quote from: John von NeumannThe sciences do not try to explain, they hardly even try to interpret, they mainly make models. By a model is meant a mathematical construct which, with the addition of certain verbal interpretations, describes observed phenomena. The justification of such a mathematical construct is solely and precisely that it is expected to work.If a theory does not have a mathematical formula predicting variables, it doesn't qualify as a physical theory.The predictive formulas of Shawyer and of McCulloch both are inversely proportional to the frequency. So, on the contrary, both Shawyer and McCulloch predict that the higher the frequency the smaller the thrust force.The formulas of Shawyer and of McCulloch have no dependence on mode shape.@Notsosureofit's formula is the only formula that shows dependence on mode shape (through the Bessel zeros, X_{mn} or X'_{mn}) and hence it has a more nuanced, subtle dependence on frequency. As the Bessel zeros X_{mn} (for TM modes) and X'_{mn} (for TE modes) increase with frequency, @Notsosureofit's thrust force increases with frequency for mode shapes with (both) high m and n (circular and radial) quantum numbers (because X_{mn} and X'_{mn} increase with frequency at a faster rate than the frequency itself) @Notsosureofit's thrust force decreases with frequency for mode shapes having (both) low m and n (circular and radial) quantum numbers (but in this case some of these low m and n mode shapes may be cut off at higher frequencies).Testing experiments have not yet been performed at a large enough range of frequencies to discriminate whether any of these formulas is correct with respect to frequency variation.In this context, performing experiments at higher microwave frequencies, perhaps using a Gunn Diode would be most helpful.

...Really hadn't thought about it, but at large X, isn't f prop X ? and NT prop X^2/f^3 ??

It occurs to me to ask a history question about all this. What on Earth occasioned Shawyer in the first place to carefully measure thrust on this odd-shaped cavity?

The team claims to have undergone seven independent reviews from experts at BAE Systems, EADS Astrium, Siemens and the IEE. The DTI has awarded the company £125,000 to develop a prototype engine as part of a three-year, £250,000 programme.Read more: http://www.theengineer.co.uk/news/defying-gravity/266633.article#ixzz3Zq1ARpVP

In a cavity with the correct radius spherical end plates there is no force on the side walls due to the travelling wave, because the walls are parallel to the group velocity vector

Quote from: Notsosureofit on 05/11/2015 12:20 pm...Really hadn't thought about it, but at large X, isn't f prop X ? and NT prop X^2/f^3 ??My recollection (from running numerical examples at the time at which you were planning to run experiments with a Gunn diode) is that at large X_{mn}, with both m~n simultaneously highest, X_{mn} increases higher than f, so that X_{mn} (f) ~ f ^y where y>1 Need y>3/2 in order for thrust force to increase with frequency.My recollection is that the thrust force predictions using your formula for the Gunn Diode frequency were much higher than the predictions of Shawyer and McCulloch.EDIT: Also the calculations for Shawyer's Flight Thruster (which I recall was run at higher frequency: 3.85GHz, twice the frequency of NASA's EM Drive tests)Is my memory correct ? (too bad that we don't have a good search function to look for things like that )

Quote from: deltaMass on 05/11/2015 01:03 pmIt occurs to me to ask a history question about all this. What on Earth occasioned Shawyer in the first place to carefully measure thrust on this odd-shaped cavity?Isn't the answer given by the statements Shawyer makes in http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=36313.0;attach=829636 ? , particularly his claim that Quote from: ShawyerIn a cavity with the correct radius spherical end plates there is no force on the side walls due to the travelling wave, because the walls are parallel to the group velocity vectorThis claim that there are no forces on the side walls is contradicted by a calculation of Maxwell's stress tensor, particularly under classical electromagnetism, as explicitly shown by Greg Egan (http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html ) for example for such a truncated cone with spherical ends. Shawyer (to my knowledge) has never adequately answered Greg Egans's proof.However, if one believes (as Shawyer does) that there are no forces on the conical side walls, then Shawyer's construction immediately follows.NOTE: To my knowledge, no closed cavity truncated cones (as in Shawyer's EM Drive) are used for microwave communication satellites.

...QuoteThe team claims to have undergone seven independent reviews from experts at BAE Systems, EADS Astrium, Siemens and the IEE. The DTI has awarded the company £125,000 to develop a prototype engine as part of a three-year, £250,000 programme.Read more: http://www.theengineer.co.uk/news/defying-gravity/266633.article#ixzz3Zq1ARpVP

At the wider end of the cone the wave travels at the speed of light, while at the other the wave travels at one tenth of that speed, due to the geometry of the waveguide.This creates higher radiation pressure at the wider end of the waveguide because the rate of change of momentum of the waves is different. Newton’s second law defines force as the rate of change of momentum.Shawyer explained that if these forces were the result of a working fluid, there would merely be a mechanical strain in the waveguide walls. But as the working fluid is replaced by an electromagnetic wave at close to the speed of light, Newtonian mechanics are replaced with the special theory of relativity.’The electromagnetic wave is going at very high velocities, so you have to apply two different reference planes,’ he said. ’It can no longer be considered a closed system. As soon as you approach the speed of light the wave can be considered completely independent of the waveguide.’ Shawyer compared the engine to a laser gyroscope, which also relies on Einstein’s laws, where attitude information is obtained from an apparently closed system.