I grinned at him. This was one of my favorite subjects. "Right now, we could probably apply a vector to something about half the size of Ceres. So, about five hundred kilometers in diameter. But it would be a tiny, tiny vector, in the range of a hundredth of a gee." I thought for a moment. "How big can we go? Well, you keep adding plates to get more push. But that makes control of plate interactions more complex. It’s just an engineering problem, though. We’re learning how to tune the drive so that most of the energy goes into moving the payload instead of keeping the plates in position. There’s no theoretical maximum that I’ve been able to find."