Here's a raft of links relating recent developments revolving around this thrustless space drive concept. At least there are some independent measurements and some theory backing things up now, so it is sort of comprehensible. Anyway, on to the links.
Please don't ask me to explain any of this to you. I'm as befuddled as the next guy. At first look, it is as if someone has added up a very long column of zeroes and arrived at a non-zero answer. But it now seems that there is more to the story.
It's a small effect, if indeed it is there at all, in these testbed machines. It may yet turn out to be a minuscule measurement error, it may turn out to be for real. Or it may turn out to be real but such a small effect as to be of no practical importance, akin to muon catalyzed fusion. Which is certainly a real thing, but a net energy-negative process.
Anyway, the way things are progressing, we'll know in a very few years.