Roger Shawyer's EMdrive is back in the news.
http://www.wired.com/dangerroom/2009/10 ... -missiles/
No conclusive demonstration model or anything to make it more plausible, however, just big plans.
EMdrive resurfaces (unexpectedly)
Re: EMdrive resurfaces (unexpectedly)
Carl White wrote:Roger Shawyer's EMdrive is back in the news.
http://www.wired.com/dangerroom/2009/10 ... -missiles/
No conclusive demonstration model or anything to make it more plausible, however, just big plans.
More talk.
Maybe it's just me, but if this were MY pet project, I would build an air table demonstrator that could be duplicated by other people.
Just for interest, I wrote the following to New Scientist letters after it appeared in that magazine. My comments weren't published, to my knowledge;
"I read with interest the article on microwave drive (09sep06, p30 et.seq.). Could this be a new insight into relativity? With keenness I set aside my concerns on the movements of warmed air through the radiator, and convection off the larger end of the cavity as sources of imparted momentum. Then the always-dangerous phrase appeared ‘..just a cord to plug it into the mains’. If 4A worth of electrons can be efficiently accelerated back around on themselves at something over 100 million radians a second (say 300MHz) internal to a device (say a magnetron) then 0.08N can be accounted for. This is the principle of the rail-gun. A battery on the test platform, fully isolated from external energy, must be used to prove the effect is a different one from the rail-gun effect (in addition to measures halting all heat convection - thermal blankets around the drive, and radiatior positioned in the centre over the axis, vented upward). But I was most disappointed with the idea that calculations showed ‘..the faster the engine moves, the more the thrust falls’. ‘Moves’ relative to what exactly? ‘Hover’ presumably means over something not moving, which means it’ll work differently at mid-day to mid-night, here on our rotating-earth?! Could this work as a zero-motion detector? To claim a tie-up with relativity theory immediately collapses. The relevance of the experimental set-up shown is also irrelevant to linear thrust in space as it is a system that accelerates about an axis, again totally compromising the integrity of a solution which claims relativity as underpinning it. Energy imparted to a moving object is not simply force x distance, but the integral of force with distance. There is a constant term that appears from that integral, which is common to all objects in a relative inertial frame. If the functional principle of this machine is that it does not share an inertial frame with us but that ‘microwaves move in their own frame of reference’, and by implication the machine does not share its inertial frame with us, then it may need an awfully large amount of energy just to keep up with us! Who knows? It’s all relative, but for sure it has to react against something in our frame to be a part of it."
Without any relative inertia, maybe this machine just disappears from our inertial frame into a parallel universe once it is fully mechanically isolated and the power switched on! Not the desired effect, but a much more interesting result!
"I read with interest the article on microwave drive (09sep06, p30 et.seq.). Could this be a new insight into relativity? With keenness I set aside my concerns on the movements of warmed air through the radiator, and convection off the larger end of the cavity as sources of imparted momentum. Then the always-dangerous phrase appeared ‘..just a cord to plug it into the mains’. If 4A worth of electrons can be efficiently accelerated back around on themselves at something over 100 million radians a second (say 300MHz) internal to a device (say a magnetron) then 0.08N can be accounted for. This is the principle of the rail-gun. A battery on the test platform, fully isolated from external energy, must be used to prove the effect is a different one from the rail-gun effect (in addition to measures halting all heat convection - thermal blankets around the drive, and radiatior positioned in the centre over the axis, vented upward). But I was most disappointed with the idea that calculations showed ‘..the faster the engine moves, the more the thrust falls’. ‘Moves’ relative to what exactly? ‘Hover’ presumably means over something not moving, which means it’ll work differently at mid-day to mid-night, here on our rotating-earth?! Could this work as a zero-motion detector? To claim a tie-up with relativity theory immediately collapses. The relevance of the experimental set-up shown is also irrelevant to linear thrust in space as it is a system that accelerates about an axis, again totally compromising the integrity of a solution which claims relativity as underpinning it. Energy imparted to a moving object is not simply force x distance, but the integral of force with distance. There is a constant term that appears from that integral, which is common to all objects in a relative inertial frame. If the functional principle of this machine is that it does not share an inertial frame with us but that ‘microwaves move in their own frame of reference’, and by implication the machine does not share its inertial frame with us, then it may need an awfully large amount of energy just to keep up with us! Who knows? It’s all relative, but for sure it has to react against something in our frame to be a part of it."
Without any relative inertia, maybe this machine just disappears from our inertial frame into a parallel universe once it is fully mechanically isolated and the power switched on! Not the desired effect, but a much more interesting result!
I refer to a previous reply of mine, re: old ideas being dragged into the news for no darned good reason but the inability of some to give up their non-viable babies!
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