Book Review of Quantum Processes Systems and Information by Benjamin Schumacher & Michael Westmoreland This is a textbook aimed at advanced undergraduate students that brings together more traditional quantum mechanics topics and quantum information theory. The book is novel both in this focus and its presentation of the material. The first five chapters discuss the basics of quantum theory using three isomorphic two-level systems: a photon in a Mach–Zehnder interferometer a spin ½ particle and a two-level atom. These chapters also develop basic quantum information concepts such as the entropy of a message interpreting unitary time evolution in terms of information capacity and the difference between distinct and distinguishable states in terms of the basic decoding and distinguishability theorems. The text then continues (chapters 6–9) with two-particle states including entanglement hidden variables the no-cloning theorem density operators and open systems. The transition to continuous systems the starting point for many quantum mechanics textbooks is made only in chapter 10 and the following chapters include standard wave mechanics found in many texts. The final three chapters revert the focus back to quantum information processing.
