Light years and time travel: an exploration of mankind's enduring fascination with light

321 Pages·2002·2.46 MB·English

LIGHT
YEARS
AND
TIME
TRAVEL
LIGHT
YEARS
AND
TIME
TRAVEL
AN EXPLORATION OF MANKIND’S
ENDURING FASCINATION WITH LIGHT
B R I A N C L E G G
John Wiley & Sons, Inc.
This book is printed on acid-free paper. 嘷∞
Copyright © 2001 by Brian Clegg. All rights reserved
Published by John Wiley & Sons, Inc., New York
Published simultaneously in Canada
First published in Great Britain in 2001 by
Judy Piatkus (Publishers) Limited
Illustrations by Rodney Paul
No part of this publication may be reproduced, stored in a retrieval system, or
transmitted in any form or by any means, electronic, mechanical, photocopying,
recording, scanning, or otherwise, except as permitted under Section 107 or 108
of the 1976 United States Copyright Act, without either the prior written
permission of the Publisher, or authorization through payment of the appropriate
per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers,
MA 01923, [phone], fax [phone]. Requests to the Publisher for
permission should be addressed to the Permissions Department,
John Wiley & Sons, Inc., 605 Third Avenue, New York, NY 10158-0012,
[phone], fax [phone], email:
To Gillian, Chelsea and Rebecca
CONTENTS
Introduction ix
1. At the Speed of Light 1
2. The Philosophers 13
3. Out of the Darkness 32
4. Engines of Light 63
5. Seeing Further 90
6. Light’s Anatomy 134
7. Death of the Ether 171
8. Fearful Symmetry 216
9. QED 246
10. Tyger! Tyger! 281
Further Reading 302
Picture Credits 306
Index 307
INTRODUCTION
And God said
‘Let there be light’:
And there was light.
GENESIS, CHAPTER 1
I G H T I S S O M E T H I N G T H AT W E TA K E F O R G R A N T E D .
It is a fact of everyday life, available at the press of
La switch. It is the absence of darkness, the gift of
the sun. It is a small part of the physics we are taught at
school, a thing of ray diagrams and geometry, without
substance. But light is not so easily compartmentalized. Its
beguiling combination of fragility and endurance, of
delicacy and power, captures the imagination just as it has
fascinated scientists through the ages.
For thousands of years, uncovering the nature of light
has proved an irresistible challenge. It forms a scientific
quest that has endured from the conjectures of the ancient
Greeks to the work of twentieth-century geniuses like
Albert Einstein and Richard Feynman. By combining
light’s history with the latest research we can assemble a
ix