"Well, sure it does. Laws of energy conversion and all. Nothing comes out of nowhere and nothing vanishes into nothingness." Not that you can necessarily trace both ends of the equation, but they are there.

And with the right instruments, you can.

"All right, we should probably look for other survivors." For better or worse, she can't be the only one. "What are you doing here, by the way? I don't think I saw you around before all of this started."