Steve Holzner - Quantum physics for dummies

Quantum Physics For Dummies, Revised Edition Published byJohn Wiley & Sons, Inc.
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Wiley publishes in a variety of print and electronic formats and by print-on-demand. Some material included with standard print versions of this book may not be included in e-books or in print-on-demand. If this book refers to media such as a CD or DVD that is not included in the version you purchased, you may download this material at http://booksupport.wiley.com . For more information about Wiley products, visit www.wiley.com. Library of Congress Control Number: 2012945682 ISBN 978-1-118-46082-5 (pbk); 978-1-118-46083-2 (ebk); ISBN 978-1-118-46086-3 (ebk); 978-1-118-846088-7 (ebk) Manufactured in the United States of America 10 9 8 7 6 5 4 3 2 1 About the Author Steven Holzner is an award-winning author of technical and science books (like Physics For Dummies and Differential Equations For Dummies). He graduated from MIT and did his PhD in physics at Cornell University, where he was on the teaching faculty for 10 years.

Hes also been on the faculty of MIT. Steve also teaches corporate groups around the country. Authors Acknowledgments Id particularly like to thank the people at Wiley: Tracy Boggier, Tim Gallan, and Danielle Voirol. Dedication To Nancy, of course! Publishers Acknowledgments Were proud of this book; please send us your comments through our Dummies online registration form located at www.dummies.com/register. Some of the people who helped bring this book to market include the following: Acquisitions, Editorial, and Media Development Senior Project Editor: Tim Gallan Acquisitions Editor: Tracy Boggier Senior Copy Editor: Danielle Voirol Assistant Editor: Erin Calligan Mooney Technical Editors: Dan Funch Wohns, Lev Kaplan, Ph.D. Editorial Manager: Michelle Hacker Editorial Assistants: Joe Niesen, Jennette ElNaggar, David Lutton Cartoons: Rich Tennant (www.the5thwave.com) Cover Photo: MEHAU KULYK / Getty Images Composition Services Project Coordinator: Erin Smith Layout and Graphics: Carl Byers, Carrie A.

Cesavice, Shawn Frazier, Nikki Gately, Melissa Smith, Christine Williams Proofreaders: Joni Heredia, Shannon Ramsey Indexer: Broccoli Information Management Publishing and Editorial for Consumer Dummies Kathleen Nebenhaus, Vice President and Executive Publisher David Palmer, Associate Publisher Kristin Ferguson-Wagstaffe, Product Development Director Publishing for Technology Dummies Andy Cummings, Vice President and Publisher Composition Services Gerry Fahey, Vice President of Production Services Debbie Stailey, Director of Composition Services Introduction P hysics as a general discipline has no limits, from the very huge (galaxy-wide) to the very small (atoms and smaller). This book is about the very small side of things thats the specialty of quantum physics. When you quantize something, you cant go any smaller; youre dealing with discrete units. Classical physics is terrific at explaining things like heating cups of coffee or accelerating down ramps or cars colliding, as well as a million other things, but it has problems when things get very small. Quantum physics usually deals with the micro world, such as what happens when you look at individual electrons zipping around. For example, electrons can exhibit both particle and wave-like properties, much to the consternation of experimenters and it took quantum physics to figure out the full picture.

Quantum physics also introduced the uncertainty principle, which says you cant know a particles exact position and momentum at the same time. And the field explains the way that the energy levels of the electrons bound in atoms work. Figuring out those ideas all took quantum physics, as physicists probed ever deeper for a way to model reality. Those topics are all coming up in this book. About This Book Because uncertainty and probability are so important in quantum physics, you cant fully appreciate the subject without getting into calculus. This book presents the need-to-know concepts, but you dont see much in the way of thought experiments that deal with cats or parallel universes.

I focus on the math and how it describes the quantum world. Ive taught physics to many thousands of students at the university level, and from that experience, I know most of them share one common trait: Confusion as to what they did to deserve such torture. Quantum Physics For Dummies, Revised Edition largely maps to a college course, but this book is different from standard texts. Instead of writing it from the physicists or professors point of view, Ive tried to write it from the readers point of view. In other words, Ive designed this book to be crammed full of the good stuff and only the good stuff. Not only that, but you can discover ways of looking at things that professors and teachers use to make figuring out problems simple.