String theory

String Theory
by George Musser

A member of Penguin Group (USA) Inc.

String Theory

String Theory
by George Musser

A member of Penguin Group (USA) Inc.

ALPHA BOOKS
Published by the Penguin Group Penguin Group (USA) Inc., 375 Hudson Street, New York, New York 10014, USA Penguin Group (Canada), 90 Eglinton Avenue East, Suite 700, Toronto, Ontario M4P 2Y3, Canada (a division ofPearson Penguin Canada Inc.) Penguin Books Ltd., 80 Strand, London WC2R 0RL, England Penguin Ireland, 25 St. Stephen’s Green, Dublin 2, Ireland (a division of Penguin Books Ltd.) Penguin Group (Australia), 250 Camberwell Road, Camberwell, Victoria 3124, Australia (a division of Pearson Australia Group Pty. Ltd.) Penguin Books India Pvt. Ltd., 11 Community Centre, Panchsheel Park, New Delhi—110017, India Penguin Group (NZ), 67 Apollo Drive, Rosedale, North Shore, Auckland 1311, New Zealand (a division of Pearson New Zealand Ltd.) Penguin Books (South Africa) (Pty.) Ltd., 24 Sturdee Avenue, Rosebank, Johannesburg 2196, South Africa Penguin Books Ltd., Registered Offices: 80 Strand, London WC2R 0RL, England

Copyright © 2008 by George Musser
All rights reserved. No part of this book shallbe reproduced, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without written permission from the publisher. No patent liability is assumed with respect to the use of the information contained herein. Although every precaution has been taken in the preparation of this book, the publisher and author assume no responsibilityfor errors or omissions. Neither is any liability assumed for damages resulting from the use of information contained herein. For information, address Alpha Books, 800 East 96th Street, Indianapolis, IN 46240. THE COMPLETE IDIOT’S GUIDE TO and Design are registered trademarks of Penguin Group (USA) Inc.

ISBN: 1-4362-4268-1 Library of Congress Catalog Card Number: 2008920831
Note: Thispublication contains the opinions and ideas of its author. It is intended to provide helpful and informative material on the subject matter covered. It is sold with the understanding that the author and publisher are not engaged in rendering professional services in the book. If the reader requires personal assistance or advice, a competent professional should be consulted. The author and publisherspecifically disclaim any responsibility for any liability, loss, or risk, personal or otherwise, which is incurred as a consequence, directly or indirectly, of the use and application of any of the contents of this book.
Publisher: Marie Butler-Knight Editorial Director: Mike Sanders Senior Managing Editor: Billy Fields Acquisitions Editor: Tom Stevens Development Editor: Susan Zingraf ProductionEditor: Kayla Dugger Copy Editor: Nancy Wagner Cartoonist: Steve Barr Book Designer: Trina Wurst Indexer: Tonya Heard Layout: Ayanna Lacey Proofreader: John Etchison

For my parents, George and Judith Musser

Contents at a Glance
Part 1: String Theory in a Nutshell
1 What Is String Theory? I break the laws of comedy by giving away my punch lines about what string theory is; what the leadingalternative theory, known as loop gravity, is; and where they stand. 2 Why Should Anybody Care? Conceptual advances in physics have played a huge role in shaping the modern world. A unified theory of physics, such as string theory, may prove equally revolutionary.

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Part 2:

The Great Clash of Worldviews
3 Einstein’s Theories What commuting by New Jersey Transit trains has to sayabout the nature of space and time. 4 The Quantum Revolution Quantum theory is no mere theory. It’s a whole way of viewing the world that manages to be both compelling and counterintuitive at the same time. 5 The Standard Model of Particles From a few varieties of building blocks, our whole universe emerges. 6 The World of the Small No ordinary microscope can probe particles, let alone whatever...