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To: servo1969

Ah, I found some “meat” about how the drive works, and it seems to work basically how I speculated it might. It directs the photons to impact one side more than the other, but instead of using a containment system, it relies on a relativistic effect to achieve this:

“The device uses a magnetron producing microwaves directed inside a specially shaped, fully enclosed tapering high Q resonant cavity whose area is greater at one end, upon which radiation pressure would act differently due to a relativistic effect caused by the action of group velocity in different frames of reference.”

“Roger Shawyer’s idea is to try to design a microwave cavity as a conical frustum in such a manner that forces due to radiation pressure on one side are greater than the other.

Cullen showed the propagation rate of electromagnetic waves in space (group velocity) and the resulting force it exerts can be varied depending on the geometry of a waveguide within which it travels.[32] The increasing confinement of a narrowing waveguide (convergent) leads to a widening wavelength and a decrease of the group velocity (lower momentum transfer). Conversely, a widening waveguide (divergent) leads to a narrowing wavelength and an increase of the group velocity (higher momentum transfer).[35]

Shawyer states that if the electromagnetic wave travelling in a tapered waveguide is bounced between two reflectors, with a large group velocity difference at the end surfaces, the force difference resulting from the radiation pressure difference will give a resultant thrust to the waveguide linking the two reflectors, in the direction of the larger surface.”

http://en.wikipedia.org/wiki/EmDrive

Jesus, if this works, it is genius. Using simple geometry of the cavity to force the waves to transform their momentum into wavelength in order to control the direction of thrust. That’s a sublime solution if ever I’ve seen one.


29 posted on 08/01/2014 5:28:53 PM PDT by Boogieman
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To: Boogieman

The science behind it is not new and has been known for over 100 years. See post #14.


31 posted on 08/01/2014 5:30:35 PM PDT by FredZarguna (Das ist nicht nur nicht richtig, es ist nicht einmal falsch!)
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To: Boogieman

The increasing confinement of a narrowing waveguide (convergent) leads to a widening wavelength and a decrease of the group velocity (lower momentum transfer
++++
I don’t understand this statement. A narrowing waveguide will support higher frequencies in the lowest waveguide modes. You can argue that the bandwidth increases as a result. But widening wavelength? What does that mean?


57 posted on 08/02/2014 8:36:16 AM PDT by InterceptPoint (Remember Mississippi)
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