Re: So what is it???
It's not a closed system. If it was it would need to either convert 100% of input energy to momentum, have perfect lossless mirrors and tiny/zero input energy or melt. None of those is happening so waste energy must be leaving the drive. The em drive may just be an extremely inefficient photon rocket and simply aiming a laser into space would do a better job.
Propellent free, maybe.. New physics, unlikely.
Biting the hand that feeds IT
