Cover image Reprinted by permission. ScienceCartoonsPlus.com. www.kendallhunt.com Send all inquiries to: 4050 Westmark Drive Dubuque, IA 52004-1840 Copyright © 2013 by David Toback ISBN 978-1-4652-2578-8 Kendall Hunt Publishing Company has the exclusive rights to reproduce this work, to prepare derivative works from this work, to publicly distribute this work, to publicly perform this work and to publicly display this work. 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, photocopy- ing, recording, or otherwise, without the prior written permission of the copyright owner. Printed in the United States of America 10 9 8 7 6 5 4 3 2 1 Contents Foreword ........................................................................................................... v Preface ............................................................................................................. vii Instructor Notes ............................................................................................. xiii Suggested Reading ..........................................................................................xvi UNIT 1: Introduction: Big and Small Stuff .................................................... 1 Chapter 1: Introduction ........................................................................... 3 Chapter 2: Going Big .............................................................................. 7 Chapter 3: Going Small......................................................................... 17 Chapter 4: Evidence and the Scientific Method .................................... 23 UNIT 2: Physics We Need: General Relativity, Dark Matter, and Quantum Mechanics .............................................................................. 35 Chapter 5: Light and Doppler Shifts .................................................... 37 Chapter 6: Gravity, General Relativity, and Dark Matter ...................... 49 Chapter 7: Atomic Physics and Quantum Mechanics ........................... 65 Chapter 8: Nuclear Physics and Chemistry ........................................... 85 Chapter 9: Temperature and Thermal Equilibrium ............................... 95 CONTENTS iii UNIT 3: The Evidence for the Big Bang ..................................................... 109 Chapter 10: The Exploding Universe .................................................. 111 Chapter 11: Expanding Space-Time ................................................... 119 Chapter 12: Photons and Hydrogen in the Universe ........................... 125 UNIT 4: The Evolution of the Universe: What Happened After the Bang .............................................................................................. 139 Chapter 13: The Early Universe .......................................................... 141 Chapter 14: After the First Three Minutes ......................................... 153 UNIT 5: Massive Things: Galaxies, Stars, and Black Holes ...................... 161 Chapter 15: Galaxies ........................................................................... 163 Chapter 16: Stars ................................................................................. 175 Chapter 17: Black Holes ...................................................................... 191 UNIT 6: Early Times, Dark Energy, and the Fate of the Universe ............ 201 Chapter 18: Possible Fates of the Universe, Dark Matter, and Dark Energy ................................................................................ 203 Chapter 19: Particle Physics, Dark Matter, and the Very Early Universe .................................................................................... 215 Chapter 20: Inflation and the Earliest Moments in Time ................... 231 iv BIG BANG, BLACK HOLES, NO MATH Foreword This book has a clear and singular goal: to explain recent exciting developments in cosmology—our understanding of how the universe works—in everyday language. This book grew out of Prof. Toback’s lectures on cosmology for non-science majors at Texas A&M University. I wish this book were published when I was teaching cosmology in my class! I agree with everything Prof. Toback says in the Preface. Our knowledge of the universe has been truly revolutionized over the last twenty years or so. However, for some reason, this revolution has not been communicated well to the people outside of the science community. The knowledge that a vast majority of people would have on the universe is most likely obsolete, as we have new and far more accurate knowledge about the universe now than twenty years ago. I am a professional cosmologist, and cosmology is what I do for a living. I have also tried to teach cosmology for non-science majors several times over the last nine years, but frankly, I do not think it was successful. A part of the difficulty was, as Prof. Toback also points out in Preface, the lack of suitable textbooks. Big Bang, Black Holes, No Math fills the gap. This is exactly the kind of book needed to communicate the exciting, revolutionizing developments in our un- derstanding of the universe to the general public, in the language that anyone can understand. This book is full of useful analogies and illustrations which will greatly help the readers relate complex phenomena in the universe to their daily experiences. And this book does not contain any equations, as advertised. The overarching question is: we now think that the universe “inflated” shortly after its birth; became hot like a fireball; created hydrogen and helium by nuclear fusion in the first three minutes; and is full of dark matter and dark energy, whose nature is currently unknown. These are the essential elements of our own universe, but what do all these mean? This book will get the readers up to speed on the forefront of cosmological studies. FOREWORD v I hope that learning and understanding how the universe works gives a joy not only to scientists who study it for a living, but also to everyone who lives in it. Big Bang, Black Holes, No Math provides an excellent starting point. Read this book, and immerse yourself in the vastness of the cosmos. May 2013 Eiichiro Komatsu Director Max-Planck-Institute for Astrophysics Garching, Germany vi BIG BANG, BLACK HOLES, NO MATH Preface This book originated out of a desire to teach a focused class on the big bang, black holes, dark matter, and cosmology to non-science majors. I thought back to when I was in college and how much I wanted to learn about these exciting top- ics. While some of the subjects were covered in basic astronomy classes, they were not the emphasis of the courses, but merely afterthoughts or covered too quickly. In physics classes, I did not get to investigate this material in-depth until I was a graduate student. Even then, the classes spent a great deal of time on advanced mathematics and didn’t get to all the interesting and exciting topics intrinsic to a study of cosmology. Also, the field of cosmology has exploded in the last ten years. It continues to be a great time of enormous progress in our understanding of the universe. Today’s students want and deserve to hear about these topics front and center. I know that many non-science students want to know more, but are apprehensive about taking physics or astronomy classes. They want to learn about the universe in a way that does not require calculations or learning about the constellations or parallax. They deserve a course tailor-made for the non-science major, yet one that does not carry the “football physics” moniker. This needs to be a very different type of course, where non-majors can undertake focused reading, discussion, and writing, delving deeply into some of the most exhilarating mysteries of our universe. As example students, I thought of my parents when they were young. While incredibly smart and well-educated (they both have Ivy League educations and PhDs), they do not know physics. Ultimately, I wanted a course they, or any other non-cosmologist, could take. I wanted to teach the course I would have enjoyed in college. This book has a number of goals. One is to share with you just how exciting our universe is today and how exciting it has been throughout its history. A second PREFACE vii important goal is for you to understand some of the evidence that gives scientists confidence that the history we will tell reflects what actually happened. One way to measure if these goals have been accomplished is if you, the reader, can communicate this understanding and enthusiasm to others. I want you to be able to effectively share it with your family, friends, co-workers, community lead- ers, and policymakers, and explain to them why it is exciting and important. My hope is that senators and members of the House of Representatives one day find this description (either from my book or from you directly) understandable and compelling. If you can explain these ideas to your parents and grandparents, I have done my job. I will admit that I am generally unhappy about how science is often taught, and about how little science the general population actually understands. Many people view science as being beyond their intellectual capabilities, or just plain dull. I cannot count the number of times I have told my airplane-seat neighbors that I am a physicist, and they reply with something such as, “Ugh… I hated that course in high school. It was boring and WAY too hard.” Frankly,