introduction to quantum mechanics 2nd edition david j griffiths

A one-semester course will have to concentrate mainly on Part I a full-year course should have room for supplementary material beyond Part II. This book is intended for a one-semester or one-year course at the junior or senior level. Some instructors, for example, may wish to treat time-independent perturbation theory immediately after Chapter 2.

Although it is important to keep the two parts logically separate, it is not necessary to study the material in the order presented here.

Accordingly, this book is divided into two parts Part I covers the basic theory, and Part II assembles an arsenal of approximation schemes, with illustrative applications. It is therefore essential to develop special techniques for attacking more realistic problems. Not only is quantum theory conceptually rich, it is also technically difficult, and exact solutions to all but the most artificial textbook examples are few and far between. But if you absolutely cannot wait, by all means read the Afterword immediately following Chapter 1. I do not believe one can intelligently discuss what quantum mechanics means until one has a firm sense of what quantum mechanics does. Apart from some essential background in Chapter 1, the deeper quasiphilosophical questions are saved for the end. The purpose of this book is to teach you how to do quantum mechanics.

Niels Bohr said, 'If you are not confused by quantum physics then you haven't really understood it' Richard Feynman remarked, 'I think I can safely say that nobody understands quantum mechanics.' There is no general consensus as to what its fundamental principles are, how it should be taught, or what it really 'means.' Every competent physicist can 'do' quantum mechanics, but the stories we tell ourselves about what we are doing are as various as the tales of Scheherazade, and almost as implausible. Unlike Newton's mechanics, or Maxwell's electrodynamics, or Einstein's relativity, quantum theory was not created-or even definitively packaged-by one individual, and it retains to this day some of the scars of its exhilarating but traumatic youth.

Introduction to quantum mechanics 2nd edition david j griffiths