Hi Allen,

Yes, this is a big debate on this drive. One side argues a breakdown of the conservation of momentum. The other says that on a global level (Mach Principle argued inertia as the effect of distant stellar objects) momentum continues to be conserved. Frankly, I found the physics mind-boggling. Even some of its proponent don’t understand how it works. Waiting for NASA’s test to see how this one goes.

Thanks,

Salman