Greetings,I am currently playing catchup (page 151), so my apologies if this has already been talked about. My question is how is the acceleration witness from the emdrive different from the Pioneer anomaly? Full disclosure time; I am not a scientist, but I am a fan of physics. Thank you for the great conversations on this forum.http://en.m.wikipedia.org/wiki/Pioneer_anomaly

Stumbled on this one:http://arxiv.org/abs/1503.06334I think it can interest @Aero

They say they have conducted an experiment in which microwave photons—relatively low energy packets of light—travelled "instantaneously" between a pair of prisms that had been moved up to 3 ft (1 m) apart. Their experiment involved an optical phenomenon known as "evanescent modes", and they claim that since evanescent modes have an imaginary wave number, they represent a "mathematical analogy" to quantum tunnelling.[32] Nimtz has also claimed that "evanescent modes are not fully describable by the Maxwell equations and quantum mechanics have to be taken into consideration."[48] Other scientists such as Herbert G. Winful and Robert Helling have argued that in fact there is nothing quantum-mechanical about Nimtz's experiments, and that the results can be fully predicted by the equations of classical electromagnetism (Maxwell's equations).[49][50]Nimtz told New Scientist magazine: "For the time being, this is the only violation of special relativity that I know of." However, other physicists say that this phenomenon does not allow information to be transmitted faster than light. Aephraim Steinberg, a quantum optics expert at the University of Toronto, Canada, uses the analogy of a train traveling from Chicago to New York, but dropping off train cars at each station along the way, so that the center of the ever shrinking main train moves forward at each stop; in this way, the speed of the center of the train exceeds the speed of any of the individual cars.[51]

...Would it be silly to think of a kind of Hawking radiation to "deflate" the frustum?

As a sanity check, what is the mode shape you predict for the above "resonance" calculation ?Do you predict resonance at a Transverse Magnetic or Transverse Electric mode ?what are the predicted mode shape quantum number m,n,p values ?TM_{mnp} ?TE_{mnp} ?Thanks

You need to develop a numerical model that calculates the guide wavelength, for the chosen mode, at discrete small increments along the cavity length and then integrate them into an effective wavelength for the whole cavity.

Quote from: OttO on 05/21/2015 02:55 pm...Would it be silly to think of a kind of Hawking radiation to "deflate" the frustum?McCulloch's explanation ( http://www.ptep-online.com/index_files/2015/PP-40-15.PDF ) is essentially akin to Hawking radiation, as Unruh radiation is akin to Hawking radiation

Rodal, thank you for the clarification. I am looking forward to reading more on this wonderful discussion. One quick stupid question: would not the shape of the cavity and the concentration of radiation in the cavity account for the higher acceleration reported? Or am I just way off? Thank you again.

Quote from: Rodal on 05/21/2015 01:15 pmAs a sanity check, what is the mode shape you predict for the above "resonance" calculation ?Do you predict resonance at a Transverse Magnetic or Transverse Electric mode ?what are the predicted mode shape quantum number m,n,p values ?TM_{mnp} ?TE_{mnp} ?ThanksRoger's bread crumb:QuoteYou need to develop a numerical model that calculates the guide wavelength, for the chosen mode, at discrete small increments along the cavity length and then integrate them into an effective wavelength for the whole cavity.Which I followed and used the guide wavelengths, generated from the Df equation, at 1,000 equally spaced diameter points between and including the end plates.

McCulloch's explanation ( http://www.ptep-online.com/index_files/2015/PP-40-15.PDF ) is essentially akin to Hawking radiation, as Unruh radiation is akin to Hawking radiation

WarptechJust had another look and your right.. jockey shorts.. laughing.The iris idea is good.Two counter rotating disks with circular holes could achieve the same thing at higher speed and minimal mechanical effort, better reliability. My experience with sliding mechanical objects has usually not been that good over a reasonable time.... just saying.I have been thinking about the cavity-resonance element of the em thruster.I may be totally wrong but I strongly suspect there is far more than just em photons bouncing around inside a tin-can happening. The wave fronts momentum "could"? have a part to play in it but I am pursuing the trail of increased-energy-level confined to a small area, and the non-traditional events that may arise. My conjecture is that the Shawyer em-drive is in a very-mild way (at present power levels) interacting/distorting/impacting/modifying/? space-time and hence its partner, Gravity, on a local level. If or when power levels ramp up to "considerable" watts.. we might see unusual things emerge in the environment immediately around the drive. The internal wavefronts inside the drive might somehow be helping to alternately create and then distort the shape and location of a G-modification?.If the guys at NASA are reading this, are you able to up-the-watts, and test for G-modification not just inside but also around the device??. {please santa}I dont have any proof to support my conjecture....yet

Quote from: TheTraveller on 05/21/2015 03:24 pmQuote from: Rodal on 05/21/2015 01:15 pmAs a sanity check, what is the mode shape you predict for the above "resonance" calculation ?Do you predict resonance at a Transverse Magnetic or Transverse Electric mode ?what are the predicted mode shape quantum number m,n,p values ?TM_{mnp} ?TE_{mnp} ?ThanksRoger's bread crumb:QuoteYou need to develop a numerical model that calculates the guide wavelength, for the chosen mode, at discrete small increments along the cavity length and then integrate them into an effective wavelength for the whole cavity.Which I followed and used the guide wavelengths, generated from the Df equation, at 1,000 equally spaced diameter points between and including the end plates.In other words, I understand that you have developed a spreadsheet model predicting the correct geometry for resonance to occur at, but that you cannot predict whether the resonance occurs in a Transverse Magnetic mode, or a Transverse Electric mode, and that you cannot predict what is the resonance mode shape variation (m. n, p numberrs) in the longitudinal, transverse and azimuthal directions of the truncated cone.Therefore we cannot check whether your ("Roger's bread crumb" ?) predicted resonance is correct.

I've even thought of using a airtight Conductive Elastic Fabric on the endplate and varying the air pressure the chamber to optimize the reflected EM wave.

...Please doc this is just a simple question, but why would absolute dimensional numbers be so important as long as you're in the ballpark for resonance? I think every device I've seen has taken into account that either you mechanically tune the EM cavity or shift the insertion frequency to optimize the thrust. I've even thought of using a airtight Conductive Elastic Fabric on the endplate and varying the air pressure the chamber to optimize the reflected EM wave.

Following Roger Shawyers kindly laid bread crumb trail, my EM Drive spreadsheet now can calc the effective internal guide wavelength and external Rf wavelength that will give resonance from end plate to end plate.As an example for the Flight Thruster big and small end diameters as below, the required end plate to end plate spacing to achieve resonance with an external Rf of 3.85GHz is as below.Alteration of either the big, small end or Rf frequency will now automatically generate a new Df and from that the end plate spacing needed to achieve resonance with the external Rf.big diameter m 0.2440000small diameter m 0.1450000cavity length m 0.1603484rf frequency Hz 3,850,000,000Calculated Df Df 0.49094slant angle Deg 28.81,000 point numerically integrated guide wavelength of the above example is: 0.0801741816I will publish the spreadsheet but would 1st like to run / verify it against other frustum dimensions and what the calculated / measured resultant resonance was and in what mode.With this spreadsheet if we know either end diameter, Rf frequency and Df, the other diameter and spacing can now be determined as all 3 dimensions and external Rf wavelength (4 variables) affect each other.NEXT STEPS:1) Determine the best way to inject the coax Rf into the Flight Thruster? Loop or Stub?2) Determine the best location to inject the Rf into the Flight Thruster?3) Determine the best way to impedance match the Flight Thruster to the impedance of the Rf generator so as to get optimal VSWR and energy delivery to inside the Flight Thruster?