If you recently bought the Superposition e-book, you may have gotten a surprise. When you opened the book, you found not Superposition, but the sequel, Supersymmetry! Not only that, but a few pages in, the book stopped suddenly. End of book. What’s going on?
The answer is simple. The entire text of Superposition is there, plus an excerpt of Supersymmetry. If you reset the book back to the beginning, you’ll find it’s all there, just as it’s supposed to be. It was a small glitch, apparently–I think in the Kindle version only–that set the book pointer at the end of the book instead of the beginning.