Darcy's explanation starts out making perfect sense to this nerd, who does work with substances and forces that can't be seen with the naked eye but are there all the same--until near the end, when she describes it as a state of being, at which point Rita's brows furrow in confusion and the comparison stops making sense.

...Putting aside Palamedes, who despite being a fellow nerd she doesn't get along with at all, studying from a book is always welcome. "If you don't mind me borrowing it. I mean, I was with you until the not a place, but a state of being part." After a moment's consideration, though, she hazards a hypothesis, "Unless you mean it's not...a physical place?"