There are a lot of books on quantum information theory. But many of them have one good feature – a desire to teach. In contrast, this book aims to speak to the reader about the subject. This book is not a tutorial on quantum information theory or quantum mechanics. It’s a nice and interesting introduction into stories about how scientists think about the result of their achievements.
After a short introduction in Chapter 2, the author attempts to consider the general question ‘What is information?’ He draws a distinction between possessing and containing information, and indicates the lines of difference between the everyday concept and Shannon’s technical one.
In Chapter 3, some of the characteristic ideas and applications of quantum information theory are presented: bits versus qubits; accessible versus specification information; the Holevo bound; the no-cloning theorem; the use of entanglement to assist communication; the examples of superdense coding and teleportation; a brief sketch of the notion of quantum information. Unfortunately, the author concludes that quantum information is simply what is produced by a quantum information source. Although the fundamental difference between the classical and quantum information is the existence of entangled states.
Chapter 4 is a case study whose purpose is to illustrate the value of recognizing clearly the logico-grammatical status of the term ‘information’ as an abstract noun: in this chapter the author investigates the phenomenon of quantum teleportation in detail.
In Chapter 5 the Deuch-Hayden approach: nonlocality, entanglement, and information flow are considered.
Chapter 6 is a discussion of some of the philosophical questions raised by the theory of quantum computation. First, whether the possibility of exponential speed-up in quantum computation provides an argument for a more substantive notion of quantum information; and second, some question regarding the status of the Church-Turing hypothesis is considered.
Chapter 7 is devoted to the connection between the theory of information and the foundation of quantum mechanics.
In Chapter 9–10 the quantum Bayesianism of Caves, Fuchs and Schack is discussed. This approach is dramatic in its starting point, which is to insists that all probabilities, even those encapsulated in a quantum state assignment, are entirely subjective.
This non-mathematical book is not for mathematicians. It will be useful to scholars of the history of science or philosophy.