[xt00]

If they have two versions of the resonant cavity, one that is tapered and one that is just a simple cylinder that to me would be a big step in the right direction to address many of the concerns. Basically the cylinder with no taper should show zero thrust. And the version with the taper should show a thrust. Then if they test that setup inside the huge Apollo program vacuum chamber far away from the side walls and change the orientation of the coolant and power wires into different orthogonal directions that sounds promising..

[mrfusion]

We don't know if the taper does anything though. If we don't have a working theory we can't really use variations of the working device to prove anything.

[xt00]

Oh I had thought that the asymmetric shape with the tapered cone shape was an important feature from the original inventor. But yea, hard to guess without more systematic theory to leverage off of yea..

[mng2]

From what I've read, the theory amounts to "there are more photons bouncing off the fat end versus the thin end hence thrust." Which personally I think is highly questionable given the low-energy regime involved.