What could possibly explain the persistence of these kinds of beliefs (from textbook authors no less!)
Well, a fact about what people in the Middle Ages believed isn’t properly in the realm of Physics. I’d expect the physicists to be mostly right about the physics they put in their textbooks, and any other stuff in there should be considered highly suspect.
Well, a fact about what people in the Middle Ages believed isn’t properly in the realm of Physics. I’d expect the physicists to be mostly right about the physics they put in their textbooks, and any other stuff in there should be considered highly suspect.
Consider it yet another exercise in skepticism.