If the universe is teeming with aliens...where is everybody?: fifty solutions to the Fermi paradox and the problem of extraterrestrial life

301 Pages·2002·4.75 MB·English

by  Stephen Webb

IF THE UNIVERSE IS TEEMING WITH ALIENS ...
WHERE IS EVERYBODY?
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IF THE UNIVERSE IS TEEMING WITH ALIENS ...
WHERE IS EVERYBODY?
FIFTYSOLUTIONS TO THE FERMI PARADOX
AND THE PROBLEM OF EXTRATERRESTRIALLIFE
Stephen Webb
Copernicus Books IN ASSOCIATION WITH Praxis Publishing Ltd.
An Imprint of Springer-Verlag
© Praxis Publishing Ltd, 2002.
All rights reserved. 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, or other-
wise, without the prior written permission of the publisher.
Published in the United States by Copernicus Books,
an imprint of Springer-Verlag New York, Inc.
Amember of BertelsmannSpringer Science+Business Media GmbH
Copernicus Books
37 East 7th Street
New York, NY10003
www.copernicusbooks.com
Library of Congress Cataloging-in-Publication Data
Webb, Stephen.
If the universe is teeming with aliens . . . where is everybody? : fifty solutions to the Fermi
paradox and the problem of extraterrestrial life / Stephen Webb.
p. cm.
Includes bibliographical references and index.
ISBN 0-387-95501-1 (acid-free paper)
1. Fermi paradox. 2. Life on other planets. 3. Fermi, Enrico, 1901–1945. I. Title.
QB54.W384 2002
576.8’39—dc21
2002073910
Manufactured in the United States of America.
Printed on acid-free paper.
9 8 7 6 5 4 3 2 1
ISBN0-387-95501-1 SPIN10879967
To Heike
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CONTENTS
Preface ix
Figure Credits xi
Chapter 1 Where Is Everybody? 1
Chapter 2 Of Fermi and Paradox 7
Enrico Fermi 8
Paradox 12
The Fermi Paradox 17
Chapter 3 They Are Here 27
SOLUTION 1 They Are Here and They Call Themselves Hungarians 28
SOLUTION 2 They Are Here and Are Meddling in Human Affairs 29
SOLUTION 3 They Were Here and Left Evidence of Their Presence 33
SOLUTION 4 They Exist and They Are Us — We Are All Aliens! 44
SOLUTION 5 The Zoo Scenario 46
SOLUTION 6 The Interdict Scenario 49
SOLUTION 7 The Planetarium Hypothesis 51
SOLUTION 8 God Exists 55
Chapter 4 They Exist But Have Not Yet Communicated 61
SOLUTION 9 The Stars Are Far Away 62
SOLUTION 10 They Have Not Had Time to Reach Us 72
SOLUTION 11 APercolation Theory Approach 74
SOLUTION 12 Bracewell–von Neumann Probes 79
SOLUTION 13 We Are Solar Chauvinists 84
SOLUTION 14 They Stay at Home... 85
SOLUTION 15 ...and Surf the Net 86
SOLUTION 16 They Are Signaling But We Do Not Know How to Listen 88
SOLUTION 17 They Are Signaling But We Do Not Know
at Which Frequency to Listen 94
SOLUTION 18 Our Search Strategy Is Wrong 102
SOLUTION 19 The Signal Is Already There in the Data 105
SOLUTION 20 We Have Not Listened Long Enough 106
SOLUTION 21 Everyone Is Listening, No One Is Transmitting 108
SOLUTION 22 Berserkers 111
SOLUTION 23 They Have No Desire to Communicate 113
SOLUTION 24 They Develop a Different Mathematics 116
SOLUTION 25 They Are Calling But We Do Not Recognize the Signal 118
SOLUTION 26 They Are Somewhere But the Universe Is Stranger
Than We Imagine 121
SOLUTION 27 AChoice of Catastrophes 122
SOLUTION 28 They Hit the Singularity 134
SOLUTION 29 Cloudy Skies Are Common 137
SOLUTION 30 Infinitely Many ETCs Exist
But Only One Within Our Particle Horizon: Us 138
Chapter 5 They Do Not Exist 141
SOLUTION 31 The Universe Is Here for Us 143
SOLUTION 32 Life Can Have Emerged Only Recently 147
SOLUTION 33 Planetary Systems Are Rare 150
SOLUTION 34 We Are the First 153
SOLUTION 35 Rocky Planets Are Rare 156
SOLUTION 36 Continuously Habitable Zones Are Narrow 158
SOLUTION 37 Jupiters Are Rare 160
SOLUTION 38 Earth Has an Optimal “Pump of Evolution” 164
SOLUTION 39 The Galaxy Is a Dangerous Place 166
SOLUTION 40 APlanetary System Is a Dangerous Place 172
SOLUTION 41 Earth’s System of Plate Tectonics Is Unique 180
SOLUTION 42 The Moon Is Unique 184
SOLUTION 43 Life’s Genesis Is Rare 189
SOLUTION 44 The Prokaryote–Eukaryote Transition Is Rare 206
SOLUTION 45 Toolmaking Species Are Rare 211
SOLUTION 46 Technological Progress Is Not Inevitable 215
SOLUTION 47 Intelligence at the Human Level Is Rare 217
SOLUTION 48 Language Is Unique to Humans 223
SOLUTION 49 Science Is Not Inevitable 231
Chapter 6 Conclusion 233
SOLUTION 50 The Fermi Paradox Resolved... 234
Chapter 7 Notes and Further Reading 241
Chapter 8 References 275
Index 283
PREFACE
This book is about the Fermi paradox — the contradiction between the
apparent absence of aliens, and the common expectation that we should
see evidence of their existence. I was fascinated by the paradox when I first
met it some 17 years ago, and it fascinates me still. Over those years, many
authors (too many to mention here, though their names appear in the ref-
erence list at the back of this book) have enthralled me with their writing
about the paradox. Their influence upon this work will be clear. I have also
discussed the paradox with many friends and colleagues; although they
are too numerous to mention individually, I am indebted to them all.
Several people have contributed directly to the writing of this book,
and I would like to take this chance to thank them. Clive Horwood of
Praxis Publishing, John Watson of Springer-Verlag and Paul Farrell of
Copernicus Books have been very supportive of the project; the book
would not have been completed had it not been for their advice and
encouragement. (I would also like to thank John for sharing his favored
resolution of the paradox over an enjoyable working lunch.) Stuart Clark
provided many useful comments on an early draft of the manuscript;
Bob Marriott and Timothy Yohn caught several errors and solecisms in a
later draft (Bob also sent me a list of 101 resolutions of the paradox — 75
of which I agree with); and I am extremely grateful to Steve Gillett for
putting me right on many scientific points. (I am, of course, responsible
for those errors that remain.) Mareike Paessler was an exceptionally
observant and helpful ProductionEditor. Her painstaking work with
Assistant Editor Anna Painter improved the text enormously. Several
authors and organizations kindly gave permission to reproduce figures;
I am particularly grateful to thank Lora Gordon, Geoffrey Landis, Ian
Wall, Susan Lendroth, Reinhard Rachel, Heather Lindsay and Merrideth
Miller for help in obtaining suitable figures. Paul Bell gently corrected
my misidentification of Feynman in Figure 28, and shared some inter-
esting ideas on the paradox. I would like to thank David Glasper for
sharing his recollections of a childhood incident that affected us both.
Finally, of course, I would like to thank my family — Heike, Ron,
Ronnie, Peter, Jackie, Emily and Abigail — for their patience. I spent
time writing that I should instead have shared with them.
Stephen Webb
Milton Keynes, July 2002
ix