Levin is a cosmologist at Barnard, and this is a short one, about 150 pages with drawings by Lia Halloran, meant to be read in a sitting. Her opening move is the one that gets you: A black hole isn’t a thing. It’s a place. There’s no object down there, no dense ball of stuff — it’s empty space bent so hard that every road out points back in. From there she walks you through what would actually happen to you going over the edge of a big one, which is not much at first, since you’d sail across the horizon without noticing, and the shredding comes later. Meanwhile anybody watching from outside sees you slow down and freeze and fade and never quite arrive. She covers Hawking radiation, the fact that they leak and eventually die, and the argument over whether what fell in is gone for good. No equations. Just her talking. It’s amazing.