From this it is clear that L is the Unruh wave length and that the cavity walls are assumed to act like a Hubble horizon.

Quote from: aero on 10/14/2014 08:13 PMFrom this it is clear that L is the Unruh wave length and that the cavity walls are assumed to act like a Hubble horizon.Fixed that for ya. This is an assumption or a speculation, not a proven fact.Correct me if I'm wrong.

1) the microwaves-photons bouncing around within the EM Drive cavity have inertia (due to their momentum), which is determined by McCulloch's quantised inertia. 2) the microwaves-photons within the EM Drive cavity undergo momentum change ("acceleration") large enough to produce McCulloch inertial changes due to Unruh radiation . The momentum change ("acceleration") must be greater than 8 c^2 / (DiameterOfBaseOfCone).3) In McCulloch's quantized inertia the Unruh waves are allowed only if they fit exactly within the Hubble horizon (or within a local Rindler horizon). For the formula to apply the EM Drive cavity walls must act like a horizon.

This is understood by any structural engineer using beam equations instead of fully 3-D equations that are unsolvable without numerical analysis.

The usefulness of closed-form solutions ... is certainly understood by Aerospace Engineers.

And just in case you are unaware of it, the best estimate of the value of the Hubble constant has changed several times during the past 10 years. Current best estimate seems to be 2.19725E-18/s with uncertainty of about 5%.It seems to be the bane of the theorist, shifting constants.

Just for fun, let's say the prediction curve is absolutely accurate and based on 70 years of experience w/ copper waveguides and resonators. Then the difference w/ these tapered chambers represent a loss of power which is going somewhere

The uncertainty experimental bars are very large and they overwhelm the very small frequency range that was explored.

What can we say about the nature of the acceleration coupling to the Unruh wave?

In McCulloch's quantised inertia the Unruh waves are allowed only if they fit exactly within the Hubble horizon (or within a local Rindler horizon). For the formula to apply the EM Drive cavity walls must act like a horizon.

Quote from: Rodal on 10/15/2014 01:25 AMIn McCulloch's quantised inertia the Unruh waves are allowed only if they fit exactly within the Hubble horizon (or within a local Rindler horizon). For the formula to apply the EM Drive cavity walls must act like a horizon.So, you have to assume that the copper walls "must" act like a horizon. Which suggests an experiment to determine if they do or not, before erecting the thoretical house of cards too high.

Whether the experimental response is an experimental artifact or whether it is thrust that may or may not be useful eventually for space propulsion, it is a fact that it is very dependent on tuning the device to reach maximum amplitude resonance. As the amplitude of resonance is in general a very nonlinear response of frequency, and as in this case the researchers are purposely seeking high Q (low damping), the bandwidth of the response is very small and hence it is difficult to produce a consistent response. This has been brought up by Ludwick in his excellent post above. The uncertainty in the results has to do with resonance, high Q (low damping), small bandwidth, knowing at what precise frequency the maximum amplitude of resonance takes place and keeping the frequency at that critical frequency. for high Q, Q ~ (ResonantFrequency) / (half-power bandwidth); so (half-power bandwidth) ~ (ResonantFrequency) / Q

Earlier I stated there had to be some kind of ceramic resonator inside. But I know think there isn't one and the concensus is that the dielectric is a large disk of polystyrene in the small end.

Quote from: Rodal on 10/15/2014 12:01 PMWhether the experimental response is an experimental artifact or whether it is thrust that may or may not be useful eventually for space propulsion, it is a fact that it is very dependent on tuning the device to reach maximum amplitude resonance. As the amplitude of resonance is in general a very nonlinear response of frequency, and as in this case the researchers are purposely seeking high Q (low damping), the bandwidth of the response is very small and hence it is difficult to produce a consistent response. This has been brought up by Ludwick in his excellent post above. The uncertainty in the results has to do with resonance, high Q (low damping), small bandwidth, knowing at what precise frequency the maximum amplitude of resonance takes place and keeping the frequency at that critical frequency. for high Q, Q ~ (ResonantFrequency) / (half-power bandwidth); so (half-power bandwidth) ~ (ResonantFrequency) / QThe resonant frequency of the device in the paper by Brady, White, et al would to be determined by two things: The diameter of the loop antenna inside the device and to a lessor extent the dielectric material near it. Earlier I stated there had to be some kind of ceramic resonator inside. But I know think there isn't one and the concensus is that the dielectric is a large disk of polystyrene in the small end. A small loop will have a natural frequency based on its inductance and parasitic capactance. The Q of a loop antenna inside a shielded and grounded enclosure will be quite high. I think the different experimental runs shown in table E of the paper were done after changing that loop. The resonant frequency and Q were then determined with the network analyzer. Bob Ludwick stated it is very difficult to get a VCO precisely on frequency when the Q is high. A better method is to use the high Q cavity itself as the frequency determining element and to build a free-running high power RF oscillator around it. It will automatically lock to the resonant frequency and track any changes due to temperature. Low phase noise RF generators use tuneable cavities driven at low power. Whether that will produce a propellantless propulsion device is still TBD. I still think there are undiscovered thermal or magnetic errors in these experiments.

science is not only reason but also passion. ...All my best

The Unruh effect is a surprising prediction of quantum field theory: From the point of view of an accelerating observer or detector, empty space contains a gas of particles at a temperature proportional to the acceleration. Direct experimental confirmation is difficult because the linear acceleration needed to reach a temperature 1 K is of order 1020 m/s2, but it is believed that an analog under centripetal acceleration is observed in the spin polarization of electrons in circular accelerators. Furthermore, the effect is necessary for consistency of the respective descriptions of observed phenomena, such as particle decay, in inertial and in accelerated reference frames; in this sense the Unruh effect does not require any verification beyond that of relativistic free field theory itself. The Unruh theory has had a major influence on our understanding of the proper relationship between mathematical formalism and (potentially) observable physics in the presence of gravitational fields, especially those near black holes.

I found a relatively new paper (dated 2014) on the Unruh effect that I could almost read mostly because it has more words than equations. http://www.scholarpedia.org/article/Unruh_effect

Those thinking that the results are an experimental artifact should seek artifact explanations that are consistent with the experimental data being linearly dependent on just these three variables.

dF = (PQ/c)*((L/w_big)-(L/w_small)) = (PQ/f)*((1/w_big)-(1/w_small)).