Quote from: TheTraveller on 05/24/2015 05:59 amQuote from: deltaMass on 05/24/2015 04:59 amTwo errors there. First, momentum is conserved at all times in all sensible reference frames for a system comprising a photon bouncing between two mirrors. There is no "borrowing from The Cosmic Badger" going on. Secondly, please don't try and use "the reference frame of a photon", accelerated or otherwise. It's a semantic null statement to put things in that frame of reference. It's also another of Shawyer's conceptual errors.Just to be clear about errors. Do you believe that Shawyer and the Chinese have made errors in measured thrust in their test devices and there is really no thrust?I can understand your curiosity about what all the other pollsters believe, when you yourself are the sole occupant of one of the offered categories.
Quote from: deltaMass on 05/24/2015 04:59 amTwo errors there. First, momentum is conserved at all times in all sensible reference frames for a system comprising a photon bouncing between two mirrors. There is no "borrowing from The Cosmic Badger" going on. Secondly, please don't try and use "the reference frame of a photon", accelerated or otherwise. It's a semantic null statement to put things in that frame of reference. It's also another of Shawyer's conceptual errors.Just to be clear about errors. Do you believe that Shawyer and the Chinese have made errors in measured thrust in their test devices and there is really no thrust?
Two errors there. First, momentum is conserved at all times in all sensible reference frames for a system comprising a photon bouncing between two mirrors. There is no "borrowing from The Cosmic Badger" going on. Secondly, please don't try and use "the reference frame of a photon", accelerated or otherwise. It's a semantic null statement to put things in that frame of reference. It's also another of Shawyer's conceptual errors.
The second generation engines will be capable of producing a specific thrust of 30kN/kW. Thus for 1 kilowatt (typical of the power in a microwave oven) a static thrust of 3 tonnes can be obtained, which is enough to support a large car. This is clearly adequate for terrestrial transport applications.The static thrust/power ratio is calculated assuming a superconducting EmDrive with a Q of 5 x 109. This Q value is routinely achieved in superconducting cavities.Note however, because the EmDrive obeys the law of conservation of energy, this thrust/power ratio rapidly decreases if the EmDrive is used to accelerate the vehicle along the thrust vector. (See Equation 16 of the theory paper). Whilst the EmDrive can provide lift to counter gravity, (and is therefore not losing kinetic energy), auxiliary propulsion is required to provide the kinetic energy to accelerate the vehicle.
[...]I also feel doing a frequency sweep to look for resonance mush be done slowly as it takes time for a high Q frustum to react to the external Rf and fully fill the cavity. Sweep too fast and you may miss the high Q sweet spots. The sweep must excite the cavity in TM mode. Putting a stub antenna through the frustum side wall will not, as far as I understand the process, excite TM mode. It will just excite TE mode. It seems you need to put the probe in the middle of one end to excite TM mode. But I'm not yet a microwave engineer, so there may be other ways to excite TM mode.Any comments on how to excite TM mode, in a frustum, with a coax feed would be most welcome.
...Dr. Rodal, for the feature article you reported on Dr. Whites simulation, "The computer code also shows that the efficiency, as measured by the thrust to input power ratio, decreases at input powers exceeding 50 kiloWatts." I assume that his theory would be properly invariant and not suffer reduction of specific thrust as a function of velocity.~Kirk
...You are correct, to excite TM01 modes you should insert your stub-antenna in the middle of one end, preferably the small end. Then do a slow sweep like you said, to fine tune the resonant frequency. IMO, it probably doesn't matter if the stub antenna extended all the way through the axis of the frustum and attached to the big end, because that end should be a Null in the p-mode, TM01p anyway. ...
Streamed live on Apr 25, 2013Special guest theorists Lisa Randall from Harvard University and Raman Sundrum from University of Maryland, who join CERN physicists to look at how the LHC experiments are investigating extra dimensions.
QuoteNote: Shawyer's analogy to a rocket is non-viable because a rocket has variable mass , it is the propellant exiting the rocket (like a bullet exiting a gun results in the gun's recoil force), the variable mass of the rocket, that is responsible for a rocket's acceleration. The EM Drive is a closed cavity and is described by Shawyer as propellant-less with nothing exiting the EM Drive.Alternatively, a rocket throws momentum out of its back end. Perhaps this is what Shawyer means when he talks about thrust. If the net force from the microwaves on the cavity is towards the small end, then the cavity must accelerate towards the small end. However being in violation of CoM there must be momentum ejected in the opposite direction, ergo Shawyers thrust. This would then act as a pushing force in the opposite direction. Quite what the ejected momentum consists of is perhaps another matter.
Note: Shawyer's analogy to a rocket is non-viable because a rocket has variable mass , it is the propellant exiting the rocket (like a bullet exiting a gun results in the gun's recoil force), the variable mass of the rocket, that is responsible for a rocket's acceleration. The EM Drive is a closed cavity and is described by Shawyer as propellant-less with nothing exiting the EM Drive.
You are correct, to excite TM01 modes you should insert your stub-antenna in the middle of one end, preferably the small end. Then do a slow sweep like you said, to fine tune the resonant frequency. IMO, it probably doesn't matter if the stub antenna extended all the way through the axis of the frustum and attached to the big end, because that end should be a Null in the p-mode, TM01p anyway.
The one "force" that ignored all this mix of neatly assembled pieces and parts and the fundamental forces had to play its game was and is space time.... By invoking a field of electromagnetic harmonics (TM212 or one like it) that creates a bubble, a null, a void, a hollowed out area within the EM cavity do we start to see a manipulation of space time and space time can violate CoE and CoM like it did in the beginning with the great expansion. ... Wonderfully the one explanation that is left and it's likely to be the one... spacetime.
Interesting.Chinese theory claims thrust directs to the small / minor end plate and the H field force is many times greater than the E field force on the end plates.Thus they excite their frustum in TE011 mode.Would appreciate the theory guys doing as much due diligence on the attached Chinese paper as has been done on Shawyers papers.
...Great video. It touches on so many topics that get discussed here on this forum.
...I thoroughly enjoyed this, Thanks Dr. Rodal!!!
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Quote from: TheTraveller on 05/24/2015 06:21 pmQuote from: Rodal----Her conclusion and final paper attached.Very interesting. Thus we see here that Prof. Yang, far from imitating Shawyer, states a completely different conclusion: that the "measured net EM thrust" is directed towards the small end (towards the "minor end plate"), (the complete opposite of what Shawyer states). She also states that this thrust direction (towards the small end) agrees with her theoretical prediction of thrust direction.
Quote from: Rodal----Her conclusion and final paper attached.
Quote from: phaseshift on 05/24/2015 04:49 pm...Great video. It touches on so many topics that get discussed here on this forum.Quote from: SeeShells on 05/24/2015 05:08 pm...I thoroughly enjoyed this, Thanks Dr. Rodal!!! As PhaseShift said it is interesting how this video deals with a number of topics we have been discussing. For example, the question is asked (by somebody at CERN) to Sundrum as to whether there is a relation of the extra dimension(s) to the Quantum Vacuum virtual particles. The answer is that this is unknown. They are using Heisenberg's uncertainty principle as a given. Sundrum emphasizes the fact that we can borrow much larger amounts of energy than we own (no need of collateral) but that you have to pay it back in an extremely small amount of time. They are using this ability to borrow larger energy from the QV in their experiments to explore energy being lost in the extra dimension(s). Thus, the issue with Dr. White's proposal is the need to payback, in a very small amount of time, any energy you may borrow (the QV being immutable and non-degradable over longer periods of time). Essentially, Dr. White's proposal is that one can default on the mortgage