AFTER the BEGINNING: a COSMIC JOURNEY THROUGH SPACE and TIME Copyright © 2004 by Imperial College Press and World Scientific Publishing Co
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Published by Imperial College Press 57 Shelton Street Covent Garden London WC2H 9HE and World Scientific Publishing Co. Pte. Ltd. 5 Toh Tuck Link, Singapore 596224 USA office: 27 Warren Street, Suite 401–402, Hackensack, NJ 07601 UK office: 57 Shelton Street, Covent Garden, London WC2H 9HE British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. Cover photo: Deep view of space from the Hubble Space Telescope. In this single view we see exactly what Laplace divined (see page 3). Remarkably, he lived centuries too early to see—as we can see now—the disk shapes that galaxies develop as they evolve under the influence of gravity and angular momentum conservation. Photo: Hickson Compact Group 87 (HCG 87); courtesy of NASA. AFTER THE BEGINNING: A COSMIC JOURNEY THROUGH SPACE AND TIME Copyright © 2004 by Imperial College Press and World Scientific Publishing Co. Pte. Ltd. All rights reserved. This book, or parts thereof, may not be reproduced in any form or by any means, electronic or mechanical, including photocopying, recording or any information storage and retrieval system now known or to be invented, without written permission from the Publisher. For photocopying of material in this volume, please pay a copying fee through the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, USA. In this case permission to photocopy is not required from the publisher. ISBN 1-86094-447-7 ISBN 1-86094-448-5 (pbk) Printed in Singapore. July 13, 2004 Book: After the Begining bk04-004 About the Author Norman K. Glendenning was born in Ontario, Canada and took his bach- elor’s and master’s degrees at McMaster University in Hamilton, Ontario. He was awarded a Ph.D. in Theoretical Physics in 1958 by Indiana Univer- sity. He was promoted to Fellow of the American Physical Society in 1968 and won the Prestigious Alexander von Humboldt Prize in 1994. He has spent his entire academic career at the University of California’s Lawrence Berkeley National Laboratory. Besides publishing more than 200 research papers in scientific journals, Dr Glendenning has written two previous books concerning his research: Direct Nuclear Reactions and Compact Stars. i July 13, 2004 Book: After the Begining bk04-004 To my dear children: Nathan, Elke, Alan v July 13, 2004 Book: After the Begining bk04-004 Ptolemy of Alexandria charting the constellations. Reproduced with permission from Bibliotheque National de France. July 13, 2004 Book: After the Begining bk04-004 Contents Preface ..................................................... xi Acknowledgments ............................................. xiii List of Figures ............................................... xv 1IslandUniverses........................................ 1 1.1 TheFirstMove.......................................... 1 1.2 LookingBack ........................................... 4 1.3 AgeandSizeoftheVisibleUniverse........................ 18 1.4 ExpandingUniverse...................................... 24 1.5 CosmologicalPrinciple.................................... 26 1.6 InflationaryEpoch....................................... 27 1.7 BeyondtheVisibleUniverse............................... 27 1.8 Boxes 1 3............................................... 28 2 The Large and the Small ............................... 30 2.1 FacetoFace............................................. 30 2.2 Space,Time,andRelativity............................... 30 2.3 PhysicsoftheVerySmall:QuantumMechanics.............. 32 2.4 Heisenberg’sUncertaintyPrinciple......................... 37 2.5 RadiationintheEarlyUniverse............................ 37 2.6 Other Planets Around Other Suns . 44 2.7 LifeonOtherPlanets .................................... 46 2.8 DifferentPointsofView .................................. 49 2.9 MilkyWay.............................................. 52 2.10 UniverseWithoutaCenter................................ 55 2.11 CosmicHorizonasSmallasaNucleon...................... 57 2.12 Box4 .................................................. 58 vii July 13, 2004 Book: After the Begining bk04-004 viii Contents 3BigBang............................................... 59 3.1 Hubble’s Discovery . 59 3.2 EvidenceforaBigBang.................................. 61 3.3 ADayWithoutYesterday................................. 63 3.4 TemperatureMeasuredatanEarlierTime.................. 68 3.5 ModelUniverses......................................... 69 3.6 ScaleFactoroftheUniverse............................... 73 3.7 TheoriesofExpansion.................................... 77 3.7.1 Thebigcrunch.................................... 78 3.7.2 Einstein deSitteruniverse ......................... 79 3.7.3 Accelerating universe . 79 3.7.4 Recyclinguniverse................................. 80 3.8 Boxes 5 8 .............................................. 81 4 Elementary Particles Fundamental Forces ............ 84 4.1 TheAtom .............................................. 84 4.2 Vacuum:Particles,Antiparticles,andDirac................. 97 4.3 AntiparticlesandAntiuniverses............................ 101 4.4 TheParticleExplosion ................................... 102 4.4.1 Cosmicrays...................................... 102 4.4.2 Laboratorybeamsofparticles....................... 104 4.5 SoManyRiches ......................................... 105 4.6 TheQuarksandLeptons.................................. 109 4.7 TheForceCarriers....................................... 114 5 The Primeval Fireball .................................. 118 5.1 CosmicEvolution........................................ 118 5.2 Heat, Temperature, and Equilibrium . 120 5.3 Planck Era (t<10−43 Seconds)............................ 121 5.4 Radiation-Dominated Era (t =10−11 Seconds to 106 Years) . 123 5.4.1 Superradiant era (t =10−11 to 10−5 seconds)......... 126 5.4.2 Hadronic era (t =10−5 to 10−3 seconds) ............. 127 5.4.3 Leptonic era (t =10−3 to1second).................. 129 5.4.4 Formation of the light elements (t = 100 seconds to10minutes).................................... 137 5.4.5 Measurement of primordial abundances of elements . 142 5.4.6 Decoupling of radiation and matter (t = 300 000 to 1 million years) . 144 5.5 CloseoftheRadiationEra ............................... 146 5.6 MatterDominance....................................... 147 5.7 Boxes 9 20.............................................. 152 July 13, 2004 Book: After the Begining bk04-004 Contents ix 6 Galaxy Clusters, Galaxies, and Stars ................... 161 6.1 StructureFormation...................................... 161 6.2 CloudCollapseintheRadiationEra ....................... 165 6.3 MatterEra.............................................. 167 6.4 GalaxyFormation........................................ 167 6.5 GalaxyTypes........................................... 170 6.6 StarFormation.......................................... 172 6.7 NovaandSupernova ..................................... 172 6.7.1 Nova:creationofawhitedwarf..................... 175 6.7.2 Supernova: creation of a neutron star or black hole . 176 6.8 Boxes 21 25............................................. 178 7TheFutureUniverse................................... 183 7.1 DarkMatter,DarkEnergy................................ 183 7.2 TheThreeAgesoftheUniverse............................ 185 7.3 TheGreatCosmologyExperiments......................... 186 7.3.1 Supernovacosmology.............................. 187 7.3.2 Theseedofourgalaxy............................. 190 7.4 Boxes 26 29............................................. 194 Books for Further Study ....................................... 198 Index ........................................................ 201 July 13, 2004 Book: After the Begining bk04-004 July 13, 2004 Book: After the Begining bk04-004 Preface I know not what I appear to the world, but to myself I seem to have been only like a boy playing on the sea-shore, and diverting myself in now and then finding a smoother pebble or a prettier shell, whilst the great ocean of truth lay all undiscovered before me. — Isaac Newton, Memoirs The heavens are a wonder to us all. So it has been throughout the ages. When we look at the night sky we see what seems a timeless panorama of stars. The slow procession of the planets and an occasional shooting star suggest a sedate motion in an otherwise eternal and unchanging universe. It isn’t so. It has long been known that stars are constantly being born in great gaseous clouds, that they develop in complexity over millions of years and then eventually die. Indeed, in the early years of the last century, the famed British astronomer Sir Arthur Eddington described the Sun as a great furnace that had enough fuel to burn for 12 billion years before it would fade away. His estimate is sound, according to all the developments in the understanding of stellar processes since then. This much is commonly known, if not the details. What is less well known, which was only recently confirmed by the many different ways in which the heavens can be viewed by modern instruments, many of them based on satellites or carried aloft by balloons, is that from the earliest moments the universe has been a cauldron of fiery activity. At the beginning, the fire was so intense that nothing in the universe now resembles what it was made of then. The entire part of the universe that astronomers can possibly see — limited as it is, not by their instruments alone, but by the distance that light can travel since the beginning — was contained