Even if the system was away from another magnet (like the sun) and it threw nothing out the back, it could propel the ship by sending out electromagnetic waves (which carry momentum). I would put big money down that they are seeing the mechanical (magnet pushes metal) effect and have not, in fact, solved the world's propulsion problems. However, a quick order of magnitude calculation...
Model the thing as a sinusoidally-varying magnetic dipole radiating in a beam straight out the back.
With
B = peak magnetic field (in tesla)
l = length scale of magnet (in meters)
T = time scale of jolt (in seconds)
F = Thrust (in pounds)
you find
F = 0.07*B^2*l^3/T.
Plugging in B = 5 T, l = 5 m, T =.01 s, I get F = 10000 pounds!
This is a pretty generous approximation, though. The beaming part is one problem (a phased array would be possible, I guess), but the sinusoidal approximation basically means they can start a new jolt on the same time scale as the jolt itself. Unlikely. But, it's an interesting number (if I didn't screw up in the derivation. It is late...)
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Model the thing as a sinusoidally-varying magnetic dipole radiating in a beam straight out the back.
With
you findPlugging in B = 5 T, l = 5 m, T = .01 s, I get F = 10000 pounds!
This is a pretty generous approximation, though. The beaming part is one problem (a phased array would be possible, I guess), but the sinusoidal approximation basically means they can start a new jolt on the same time scale as the jolt itself. Unlikely. But, it's an interesting number (if I didn't screw up in the derivation. It is late...)