Just skimmed the EM section: I didn't catch anything egregiously wrong, per se (but again, I only skimmed it), but it's mostly fluff, and the actual physics con

Just skimmed the EM section: I didn't catch anything egregiously wrong, per se (but again, I only skimmed it), but it's mostly fluff, and the actual physics content that does it exist is targeted at wildly different levels. For instance the author goes from "an electric field is like a tiny arrow attached to every point in space" (day 1 of intro physics for non-physics majors) in chapter 1 to assuming the reader knows what covariant derivatives are (advanced undergraduate) in chapter 2. I would strongly recommend against using these books.