Heart of Darkness

Acknowledgments ix

Preface xiii

- Cosmology Becomes Data-driven Science xiii

- Outline of the Journey We Will Take xix

Prologue: From Myth to Reality 1

- Astronomy: The Endless Frontier 1

- Charting and Modeling the Heavens 3

- Copernicus: "The Last of the Greek Cosmologists" 6

- Galileo: A New Approach to Mechanics and Cosmology 9

- The Impact of Copernicus: Kepler's Laws 13

- Isaac Newton and Gravity 15

- William Herschel Discovers the Universe 20

- Understanding the Universe Becomes a New Kind of Science 24

One: Einstein's Toolkit, and How to Use It 27

- Overconfidence among the Cognoscenti at the Dawn of the Twentieth Century 27

- Revolution in Physics: The Inception of Quantum Theory and Relativity 30

- Special Relativity 33

- General Relativity 36

- General Relativity Is Tested, Passes the Test, and Is a Sensation 41

- Cosmological Solutions to Einstein's Equations 47

Two: The Realm of the Nebulae 52

- New Instruments in a Better Climate Unveil a New World 52

- A Universe of Galaxies Is Confirmed 63

- A Cosmological Model to Fit the New Data: Enter, Georges Lemaître 66

- Physical Cosmology and the Expanding Universe 70

- Lemaître's Synthesis Model Foretells the Contribution of Dark Energy 75

- Hubble's Achievements 79

- Big Science to Attack the Big Problem 81

- The Steady State Model Universe and the Big Bang 84

Three: Let's Do Cosmology! 89

- The Big Bang: A Starting Point That Cannot Be Escaped 89

- Observational Cosmology, the Biggest Puzzle to Be Solved with the Biggest Telescope 93

- The Grand Project Was Initially Too Difficult 97

Four: Discovering the Big Bang 102

- Did Our Universe Have an Explosive Birth? 102

- What Makes the Stars Shine? 104

- Nuclear Astrophysics Moves to the Cosmos 109

- The Fireball in Which the First Chemical Elements Were Made 114

- Direct Radio Observations of the Big Bang Fireball 118

- Understanding the Big Bang 125

Five: The Origin of Structure in the Universe 130

- "In the Beginning"--Why an Explanation Is Needed 130

- Structure within the Expanding Universe 136

- The Elusive Standard Candle: Beatrice Tinsley Changes the Game 139

- Real Cosmic Structure Found and Cataloged by Fritz Zwicky 146

- Understanding the Origin of Structure Becomes Serious Science 149

- Cosmic Inflation 155

- The Seeds of Cosmic Structure Are Discovered 162

- Closing the Loop: How Do Seeds Grow to Galaxies? 168

Six: Dark Matter--or Fritz Zwicky's Greatest Invention 174

- How the Earth Was Weighed 174

- Finding the Mass of the Andromeda Galaxy 181

- Zwicky Finds Dark Matter in Clusters of Galaxies in the 1930s 184

- The Rediscovery of Dark Matter in the 1970s 187

- Rotation Curves Confirm the Case for Dark Matter 193

- More Recent Multiple Lines of Evidence for Dark Matter 197

Seven: Dark Energy--or Einstein's Greatest Blunder 202

- A Curious Situation 202

- Will Gravity Lead to a Collapse of the Solar System? 203

- Expected and Unexpected Motions of Thrown Stones and Hubble's Universe 205

- The Invention of the Cosmological Constant or Dark Energy: 1915 209

- The Revival of Dark Energy in the 1970s 215

- New Arguments and New Evidence--Dark Energy Confirmed in the 1990s 220

- Dark Energy Fills the Gap, Allowing the Flat, "Just Right" Universe 222

Eight: The Modern Paradigm and the Limits of Our Knowledge 229

- We Have Come a Long Way 229

- The Matter and Energy Content of the Universe 231

- The Global Cosmological Solution and the Cosmic Triangle 238

- In the Beginning 244

- Structure in the Universe 245

- The Supercomputer Approach 248

Nine: The Frontier: Major Mysteries That Remain 253

- Dark Matter 253

- Dark Energy 255

- Inflation 257

- Giant Black Holes 260

- Fine-Tuning 261

- Summing Up 262

Appendixes 263
Glossary 281
Bibliography 291
Index 295