We have arrived at this position of eminence in a stunningly short time. Behaviorally modern human beings-that is, people who can speak and make art and organize complex activities-have existed for only about 0.0001 percent of Earth’s history. But surviving for even that little while has required a nearly endless string of good fortune.

We really are at the beginning of it all. The trick, of course, is to make sure we never find the end. And that, almost certainly, will require a good deal more than lucky breaks.

NOTES

CHAPTER 1 HOW TO BUILD A UNIVERSE

“Protons are so small that . . .” Bodanis, E = mc2, p. 111.

“Now pack into that tiny, tiny space . . .” Guth, The Inflationary Universe, p. 254.

“about 13.7 billion years . . .”U.S. News and World Report, “How Old Is the Universe?” August 18-25, 1997, pp. 34-36; and New York Times, “Cosmos Sits for Early Portrait, Gives Up Secrets,” February 12, 2003, p. 1.

“the moment known to science as t = 0.” Guth, p. 86.

“They climbed back into the dish . . .” Lawrence M. Krauss, “Rediscovering Creation,” in Shore, Mysteries of Life and the Universe, p. 50.

“an instrument that might do the job . . .” Overbye, Lonely Hearts of the Cosmos, p. 153.

“They had found the edge of the universe . . .”Scientific American, “Echoes from the Big Bang,” January 2001, pp. 38-43; and Nature, “It All Adds Up,” December 19-26, 2002, p. 733.

“Penzias and Wilson’s finding pushed our acquaintance . . .” Guth, p. 101.

“about 1 percent of the dancing static . . .” Gribbin, In the Beginning, p. 18.

“These are very close to religious questions . . .”New York Times, “Before the Big Bang, There Was . . . What?” May 22, 2001, p. F1.

“or one 10 million trillion trillion trillionth . . .” Alan Lightman, “First Birth,” in Shore, Mysteries of Life and the Universe, p. 13.

“He was thirty-two years old . . .” Overbye, p. 216.

“The lecture inspired Guth to take an interest . . .” Guth, p. 89.

“doubling in size every 10-34 seconds.” Overbye, p. 242.

“it changed the universe . . .”New Scientist, “The First Split Second,” March 31, 2001, pp. 27-30.

“perfectly arrayed for the creation of stars . . .”Scientific American, “The First Stars in the Universe,” December 2001, pp. 64-71; and New York Times, “Listen Closely: From Tiny Hum Came Big Bang,” April 30, 2001, p. 1.

“no one had counted the failed attempts.” Quoted by Guth, p. 14.

“He makes an analogy with a very large clothing store . . .”Discover, November 2000.

“with the slightest tweaking of the numbers . . .” Rees, Just Six Numbers, p. 147.

“gravity may turn out to be a little too strong . . .”Financial Times, “Riddle of the Flat Universe,” July 1-2, 2000; and Economist, “The World Is Flat After All,” May 20, 2000, p. 97.

“the galaxies are rushing apart.” Weinberg, Dreams of a Final Theory, p. 34.

“Scientists just assume that we can’t really be the center . . .” Hawking, A Brief History of Time, p. 47.

“the universe we know and can talk about . . .” Hawking, A Brief History of Time, p. 13.

“the number of light-years to the edge . . .” Rees, p. 147.

CHAPTER 2 WELCOME TO THE SOLAR SYSTEM

“From the tiniest throbs and wobbles . . .”New Yorker, “Among Planets,” December 9, 1996, p. 84.

“less than the energy of a single snowflake . . .” Sagan, Cosmos, p. 217.

“a young astronomer named James Christy . . .” U.S. Naval Observatory press release, “20th Anniversary of the Discovery of Pluto’s Moon Charon,” June 22, 1998.

“Pluto was much smaller than anyone had supposed,”Atlantic Monthly, “When Is a Planet Not a Planet?” February 1998, pp. 22-34.

“In the words of the astronomer Clark Chapman . . .” Quoted on PBS Nova, “Doomsday Asteroid,” first aired April 29, 1997.

“it took seven years for anyone to spot the moon again . . .” U.S. Naval Observatory press release, “20th Anniversary of the Discovery of Pluto’s Moon Charon,” June 22, 1998.

“. . . after a year’s patient searching he somehow spotted Pluto . . .” Tombaugh paper, “The Struggles to Find the Ninth Planet,” from NASA website.

“there may be a Planet X out there . . .”Economist, “X Marks the Spot,” October 16, 1999, p. 83.

“The Kuiper belt was actually theorized . . .”Nature, “Almost Planet X,” May 24, 2001, p. 423.

“Only on February 11, 1999, did Pluto return . . .”Economist, “Pluto Out in the Cold,” February 6, 1999, p. 85.

“over six hundred additional Trans-Neptunian Objects . . .”Nature, “Seeing Double in the Kuiper Belt,” December 12, 2002, p. 618.

“about the same as a lump of charcoal . . .”Nature, “Almost Planet X,” May 24, 2001, p. 423.

“now flying away from us . . .” PBS NewsHour transcript, August 20, 2002.

“fills less than a trillionth of the available space.”Natural History, “Between the Planets,” October 2001, p. 20.

“The total now is ‘at least ninety . . .’ ”New Scientist, “Many Moons,” March 17, 2001, p. 39; and Economist, “A Roadmap for Planet-Hunting,” April 8, 2000, p. 87.

“we won’t reach the Oort cloud . . .” Sagan and Druyan, Comet, p. 198.

“probably result in the deaths of all the crew . . .”New Yorker, “Medicine on Mars,” February 14, 2000, p. 39.

“the comets drift in a stately manner . . .” Sagan and Druyan, p. 195.

“The most perfect vacuum ever created . . .” Ball, H2O, p. 15.

“ Our nearest neighbor in the cosmos,” Proxima Centauri . . .” Guth, p. 1; and Hawking, A Brief History of Time, p. 39.

“The average distance between stars . . .” Dyson, Disturbing the Universe, p. 251.

“If we were randomly inserted . . .” Sagan, p. 52.

CHAPTER 3 THE REVEREND EVANS’S UNIVERSE

“the energy of a hundred billion suns . . .” Ferris, The Whole Shebang, p. 37.

“It’s like a trillion hydrogen bombs . . .” Robert Evans, interview by author, Hazelbrook, Australia, September 2, 2001.

“a chapter on autistic savants . . .” Sacks, An Anthropologist on Mars, p. 198.

“an irritating buffoon . . .” Thorne, Black Holes and Time Warps, p. 164.

“refused to be left alone with him . . .” Ferris, The Whole Shebang, p. 125.

“Zwicky threatened to kill Baade . . .” Overbye, p. 18.

“Atoms would literally be crushed together . . .”Nature, “Twinkle, Twinkle, Neutron Star,” November 7, 2002, p. 31.

“the biggest bang in the universe . . .” Thorne, p. 171.

“hasn’t been verified yet.” Thorne, p. 174.

“one of the most prescient documents . . .” Thorne, p. 174.

“he did not understand the laws of physics . . .” Thorne, p. 174.

“wouldn’t attract serious attention for nearly four decades . . .” Overbye, p. 18.

“Only about 6,000 stars . . .” Harrison, Darkness at Night, p. 3.

“In 1987 Saul Perlmutter . . .” BBC Horizon documentary, “From Here to Infinity,” transcript of program first broadcast February 28, 1999.

“The news of such an event . . .” John Thorstensen, interview by author, Hanover, New Hampshire, December 5, 2001.