The combination of two of the twentieth century's most influential and revolutionary scientific theories, information theory and quantum mechanics, gave rise to a radically new view of computing and information. Quantum information processing explores the implications of using quantum mechanics instead of classical mechanics to model information and its processing. Quantum computing is not about changing the physical substrate on which computation is done from classical to quantum but about changing the notion of computation itself, at the most basic level. The fundamental unit of computation is no longer the bit but the quantum bit or qubit. This comprehensive introduction to the field offers a thorough exposition of quantum computing and the underlying concepts of quantum physics, explaining all the relevant mathematics and offering numerous examples. With its careful development of concepts and thorough explanations, the book makes quantum computing accessible to students and professionals in mathematics, computer science, and engineering. A reader with no prior knowledge of quantum physics (but with sufficient knowledge of linear algebra) will be able to gain a fluent understanding by working through the book.
But very smooth and more abstract/mathematical than most introductory texts - and I mean this in a good way. The important results are highlighted and interrelated and the overall organization is clear. The proofs and algorithms are a little terse and compact for what is meant to be an introduction. And yet some of the detailed examples get a bit messy and hard to follow. There is much more material on error correction and fault tolerance than is usually found in an introductory text. But its all pretty good and understandable and of course fundamental to the subject. Probably not the first text to go to. But once you have the basics a good next book to go through.
A fascinating subject well explained but the introduction is not that "gentle". The exercises are extremely interesting, and definitely part of the learning process, unfortunately the authors did not publish solutions.
A really good (and in-depth) introduction to the theory behind quantum computing. A good source if you've got the background (quantum physics and linear algebra) to study it.